kasan_remap_early_shadow_ro() and kasan_unmap_early_shadow_vmalloc()
are both updating the early shadow mapping: the first one sets
the mapping read-only while the other clears the mapping.
Refactor and create kasan_update_early_region()
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8c496c0828de2608c7c940c45525d177e91b6f1b.1589866984.git.christophe.leroy@csgroup.eu
Commit 45ff3c5595 ("powerpc/kasan: Fix parallel loading of
modules.") added spinlocks to manage parallele module loading.
Since then commit 47febbeeec ("powerpc/32: Force KASAN_VMALLOC for
modules") converted the module loading to KASAN_VMALLOC.
The spinlocking has then become unneeded and can be removed to
simplify kasan_init_shadow_page_tables()
Also remove inclusion of linux/moduleloader.h and linux/vmalloc.h
which are not needed anymore since the removal of modules management.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/81a4d3aee8b82bc1355595935c8f4ad9d3b22a83.1589866984.git.christophe.leroy@csgroup.eu
In case (k_start & PAGE_MASK) doesn't equal (kstart), 'va' will never be
NULL allthough 'block' is NULL
Check the return of memblock_alloc() directly instead of
the resulting address in the loop.
Fixes: 509cd3f2b4 ("powerpc/32: Simplify KASAN init")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7cb8ca82042bfc45a5cfe726c921cd7e7eeb12a3.1589866984.git.christophe.leroy@csgroup.eu
This option increases the number of SLB misses by limiting the number
of kernel SLB entries, and increased flushing of cached lookaside
information. This helps stress test difficult to hit paths in the
kernel.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Relocate the code into arch/powerpc/mm, s/torture/stress/]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200511125825.3081305-1-mpe@ellerman.id.au
With a 64K page size flush with start and end:
(start, end) = (721f680d0000, 721f680e0000)
results in:
(hstart, hend) = (721f68200000, 721f68000000)
ie. hstart is above hend, which indicates no huge page flush is
needed.
However the current logic incorrectly sets hflush = true in this case,
because hstart != hend.
That causes us to call __tlbie_va_range() passing hstart/hend, to do a
huge page flush even though we don't need to. __tlbie_va_range() will
skip the actual tlbie operation for start > end. But it will still end
up calling fixup_tlbie_va_range() and doing the TLB fixups in there,
which is harmless but unnecessary work.
Reported-by: Bharata B Rao <bharata@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Drop else case, hflush is already false, flesh out change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200513030616.152288-1-aneesh.kumar@linux.ibm.com
This reverts commit 697ece78f8.
The implementation of SWAP on powerpc requires page protection
bits to not be one of the least significant PTE bits.
Until the SWAP implementation is changed and this requirement voids,
we have to keep at least _PAGE_RW outside of the 3 last bits.
For now, revert to previous PTE bits order. A further rework
may come later.
Fixes: 697ece78f8 ("powerpc/32s: reorder Linux PTE bits to better match Hash PTE bits.")
Reported-by: Rui Salvaterra <rsalvaterra@gmail.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b34706f8de87f84d135abb5f3ede6b6f16fb1f41.1589969799.git.christophe.leroy@csgroup.eu
Introduce a probe_user_read_inst() function to use in cases where
probe_user_read() is used for getting an instruction. This will be
more useful for prefixed instructions.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
[mpe: Don't write to *inst on error, fold in __user annotations]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-14-jniethe5@gmail.com
Currently unsigned ints are used to represent instructions on powerpc.
This has worked well as instructions have always been 4 byte words.
However, ISA v3.1 introduces some changes to instructions that mean
this scheme will no longer work as well. This change is Prefixed
Instructions. A prefixed instruction is made up of a word prefix
followed by a word suffix to make an 8 byte double word instruction.
No matter the endianness of the system the prefix always comes first.
Prefixed instructions are only planned for powerpc64.
Introduce a ppc_inst type to represent both prefixed and word
instructions on powerpc64 while keeping it possible to exclusively
have word instructions on powerpc32.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Fix compile error in emulate_spe()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-12-jniethe5@gmail.com
In preparation for using a data type for instructions that can not be
directly used with the '>>' operator use a function for getting the op
code of an instruction.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-9-jniethe5@gmail.com
In preparation for introducing a more complicated instruction type to
accommodate prefixed instructions use an accessor for getting an
instruction as a u32.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-8-jniethe5@gmail.com
In preparation for instructions having a more complex data type start
using a macro, ppc_inst(), for making an instruction out of a u32. A
macro is used so that instructions can be used as initializer elements.
Currently this does nothing, but it will allow for creating a data type
that can represent prefixed instructions.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Change include guard to _ASM_POWERPC_INST_H]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-7-jniethe5@gmail.com
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200507185755.GA15014@embeddedor
MADV_DONTNEED holds mmap_sem in read mode and that implies a
parallel page fault is possible and the kernel can end up with a level 1 PTE
entry (THP entry) converted to a level 0 PTE entry without flushing
the THP TLB entry.
Most architectures including POWER have issues with kernel instantiating a level
0 PTE entry while holding level 1 TLB entries.
The code sequence I am looking at is
down_read(mmap_sem) down_read(mmap_sem)
zap_pmd_range()
zap_huge_pmd()
pmd lock held
pmd_cleared
table details added to mmu_gather
pmd_unlock()
insert a level 0 PTE entry()
tlb_finish_mmu().
Fix this by forcing a tlb flush before releasing pmd lock if this is
not a fullmm invalidate. We can safely skip this invalidate for
task exit case (fullmm invalidate) because in that case we are sure
there can be no parallel fault handlers.
This do change the Qemu guest RAM del/unplug time as below
128 core, 496GB guest:
Without patch:
munmap start: timer = 196449 ms, PID=6681
munmap finish: timer = 196488 ms, PID=6681 - delta = 39ms
With patch:
munmap start: timer = 196345 ms, PID=6879
munmap finish: timer = 196714 ms, PID=6879 - delta = 369ms
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-23-aneesh.kumar@linux.ibm.com
Now that all the lockless page table walk is careful w.r.t the PTE
address returned, we can now revert
commit: 13bd817bb8 ("powerpc/thp: Serialize pmd clear against a linux page table walk.")
We also drop the equivalent IPI from other pte updates routines. We still keep
IPI in hash pmdp collapse and that is to take care of parallel hash page table
insert. The radix pmdp collapse flush can possibly be removed once I am sure
generic code doesn't have the any expectations around parallel gup walk.
This speeds up Qemu guest RAM del/unplug time as below
128 core, 496GB guest:
Without patch:
munmap start: timer = 13162 ms, PID=7684
munmap finish: timer = 95312 ms, PID=7684 - delta = 82150 ms
With patch:
munmap start: timer = 196449 ms, PID=6681
munmap finish: timer = 196488 ms, PID=6681 - delta = 39ms
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-21-aneesh.kumar@linux.ibm.com
Don't fetch the pte value using lockless page table walk. Instead use the value from the
caller. hash_preload is called with ptl lock held. So it is safe to use the
pte_t address directly.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-6-aneesh.kumar@linux.ibm.com
This is only used with init_mm currently. Walking init_mm is much simpler
because we don't need to handle concurrent page table like other mm_context
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-5-aneesh.kumar@linux.ibm.com
This makes the pte_present check stricter by checking for additional _PAGE_PTE
bit. A level 1 pte pointer (THP pte) can be switched to a pointer to level 0 pte
page table page by following two operations.
1) THP split.
2) madvise(MADV_DONTNEED) in parallel to page fault.
A lockless page table walk need to make sure we can handle such changes
gracefully.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-4-aneesh.kumar@linux.ibm.com
If multiple threads in userspace keep changing the protection keys
mapping a range, there can be a scenario where kernel takes a key fault
but the pkey value found in the siginfo struct is a permissive one.
This can confuse the userspace as shown in the below test case.
/* use this to control the number of test iterations */
static void pkeyreg_set(int pkey, unsigned long rights)
{
unsigned long reg, shift;
shift = (NR_PKEYS - pkey - 1) * PKEY_BITS_PER_PKEY;
asm volatile("mfspr %0, 0xd" : "=r"(reg));
reg &= ~(((unsigned long) PKEY_BITS_MASK) << shift);
reg |= (rights & PKEY_BITS_MASK) << shift;
asm volatile("mtspr 0xd, %0" : : "r"(reg));
}
static unsigned long pkeyreg_get(void)
{
unsigned long reg;
asm volatile("mfspr %0, 0xd" : "=r"(reg));
return reg;
}
static int sys_pkey_mprotect(void *addr, size_t len, int prot, int pkey)
{
return syscall(SYS_pkey_mprotect, addr, len, prot, pkey);
}
static int sys_pkey_alloc(unsigned long flags, unsigned long access_rights)
{
return syscall(SYS_pkey_alloc, flags, access_rights);
}
static int sys_pkey_free(int pkey)
{
return syscall(SYS_pkey_free, pkey);
}
static int faulting_pkey;
static int permissive_pkey;
static pthread_barrier_t pkey_set_barrier;
static pthread_barrier_t mprotect_barrier;
static void pkey_handle_fault(int signum, siginfo_t *sinfo, void *ctx)
{
unsigned long pkeyreg;
/* FIXME: printf is not signal-safe but for the current purpose,
it gets the job done. */
printf("pkey: exp = %d, got = %d\n", faulting_pkey, sinfo->si_pkey);
fflush(stdout);
assert(sinfo->si_code == SEGV_PKUERR);
assert(sinfo->si_pkey == faulting_pkey);
/* clear pkey permissions to let the faulting instruction continue */
pkeyreg_set(faulting_pkey, 0x0);
}
static void *do_mprotect_fault(void *p)
{
unsigned long rights, pkeyreg, pgsize;
unsigned int i;
void *region;
int pkey;
srand(time(NULL));
pgsize = sysconf(_SC_PAGESIZE);
rights = PKEY_DISABLE_WRITE;
region = p;
/* allocate key, no permissions */
assert((pkey = sys_pkey_alloc(0, PKEY_DISABLE_ACCESS)) > 0);
pkeyreg_set(4, 0x0);
/* cache the pkey here as the faulting pkey for future reference
in the signal handler */
faulting_pkey = pkey;
printf("%s: faulting pkey = %d\n", __func__, faulting_pkey);
/* try to allocate, mprotect and free pkeys repeatedly */
for (i = 0; i < NUM_ITERATIONS; i++) {
/* sync up with the other thread here */
pthread_barrier_wait(&pkey_set_barrier);
/* make sure that the pkey used by the non-faulting thread
is made permissive for this thread's context too so that
no faults are triggered because it still might have been
set to a restrictive value */
// pkeyreg_set(permissive_pkey, 0x0);
/* sync up with the other thread here */
pthread_barrier_wait(&mprotect_barrier);
/* perform mprotect */
assert(!sys_pkey_mprotect(region, pgsize, PROT_READ | PROT_WRITE, pkey));
/* choose a random byte from the protected region and
attempt to write to it, this will generate a fault */
*((char *) region + (rand() % pgsize)) = rand();
/* restore pkey permissions as the signal handler may have
cleared the bit out for the sake of continuing */
pkeyreg_set(pkey, PKEY_DISABLE_WRITE);
}
/* free pkey */
sys_pkey_free(pkey);
return NULL;
}
static void *do_mprotect_nofault(void *p)
{
unsigned long pgsize;
unsigned int i, j;
void *region;
int pkey;
pgsize = sysconf(_SC_PAGESIZE);
region = p;
/* try to allocate, mprotect and free pkeys repeatedly */
for (i = 0; i < NUM_ITERATIONS; i++) {
/* allocate pkey, all permissions */
assert((pkey = sys_pkey_alloc(0, 0)) > 0);
permissive_pkey = pkey;
/* sync up with the other thread here */
pthread_barrier_wait(&pkey_set_barrier);
pthread_barrier_wait(&mprotect_barrier);
/* perform mprotect on the common page, no faults will
be triggered as this is most permissive */
assert(!sys_pkey_mprotect(region, pgsize, PROT_READ | PROT_WRITE, pkey));
/* free pkey */
assert(!sys_pkey_free(pkey));
}
return NULL;
}
int main(int argc, char **argv)
{
pthread_t fault_thread, nofault_thread;
unsigned long pgsize;
struct sigaction act;
pthread_attr_t attr;
cpu_set_t fault_cpuset, nofault_cpuset;
unsigned int i;
void *region;
/* allocate memory region to protect */
pgsize = sysconf(_SC_PAGESIZE);
assert(region = memalign(pgsize, pgsize));
CPU_ZERO(&fault_cpuset);
CPU_SET(0, &fault_cpuset);
CPU_ZERO(&nofault_cpuset);
CPU_SET(8, &nofault_cpuset);
assert(!pthread_attr_init(&attr));
/* setup sigsegv signal handler */
act.sa_handler = 0;
act.sa_sigaction = pkey_handle_fault;
assert(!sigprocmask(SIG_SETMASK, 0, &act.sa_mask));
act.sa_flags = SA_SIGINFO;
act.sa_restorer = 0;
assert(!sigaction(SIGSEGV, &act, NULL));
/* setup barrier for the two threads */
pthread_barrier_init(&pkey_set_barrier, NULL, 2);
pthread_barrier_init(&mprotect_barrier, NULL, 2);
/* setup and start threads */
assert(!pthread_create(&fault_thread, &attr, &do_mprotect_fault, region));
assert(!pthread_setaffinity_np(fault_thread, sizeof(cpu_set_t), &fault_cpuset));
assert(!pthread_create(&nofault_thread, &attr, &do_mprotect_nofault, region));
assert(!pthread_setaffinity_np(nofault_thread, sizeof(cpu_set_t), &nofault_cpuset));
/* cleanup */
assert(!pthread_attr_destroy(&attr));
assert(!pthread_join(fault_thread, NULL));
assert(!pthread_join(nofault_thread, NULL));
assert(!pthread_barrier_destroy(&pkey_set_barrier));
assert(!pthread_barrier_destroy(&mprotect_barrier));
free(region);
puts("PASS");
return EXIT_SUCCESS;
}
The above test can result the below failure without this patch.
pkey: exp = 3, got = 3
pkey: exp = 3, got = 4
a.out: pkey-siginfo-race.c💯 pkey_handle_fault: Assertion `sinfo->si_pkey == faulting_pkey' failed.
Aborted
Check for vma access before considering this a key fault. If vma pkey allow
access retry the acess again.
Test case is written by Sandipan Das <sandipan@linux.ibm.com> hence added SOB
from him.
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-3-aneesh.kumar@linux.ibm.com
Fetch pkey from vma instead of linux page table. Also document the fact that in
some cases the pkey returned in siginfo won't be the same as the one we took
keyfault on. Even with linux page table walk, we can end up in a similar scenario.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-2-aneesh.kumar@linux.ibm.com
WRITE_RO lkdtm test works.
But when selecting CONFIG_DEBUG_RODATA_TEST, the kernel reports
rodata_test: test data was not read only
This is because when rodata test runs, there are still old entries
in TLB.
Flush TLB after setting kernel pages RO or NX.
Fixes: d5f17ee964 ("powerpc/8xx: don't disable large TLBs with CONFIG_STRICT_KERNEL_RWX")
Cc: stable@vger.kernel.org # v5.1+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/485caac75f195f18c11eb077b0031fdd2bb7fb9e.1587361039.git.christophe.leroy@c-s.fr
devm_memremap_pages() is currently used by the PCI P2PDMA code to create
struct page mappings for IO memory. At present, these mappings are
created with PAGE_KERNEL which implies setting the PAT bits to be WB.
However, on x86, an mtrr register will typically override this and force
the cache type to be UC-. In the case firmware doesn't set this
register it is effectively WB and will typically result in a machine
check exception when it's accessed.
Other arches are not currently likely to function correctly seeing they
don't have any MTRR registers to fall back on.
To solve this, provide a way to specify the pgprot value explicitly to
arch_add_memory().
Of the arches that support MEMORY_HOTPLUG: x86_64, and arm64 need a
simple change to pass the pgprot_t down to their respective functions
which set up the page tables. For x86_32, set the page tables
explicitly using _set_memory_prot() (seeing they are already mapped).
For ia64, s390 and sh, reject anything but PAGE_KERNEL settings -- this
should be fine, for now, seeing these architectures don't support
ZONE_DEVICE.
A check in __add_pages() is also added to ensure the pgprot parameter
was set for all arches.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Badger <ebadger@gigaio.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200306170846.9333-7-logang@deltatee.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In prepartion to support a pgprot_t argument for arch_add_memory().
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Eric Badger <ebadger@gigaio.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200306170846.9333-6-logang@deltatee.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The mhp_restrictions struct really doesn't specify anything resembling a
restriction anymore so rename it to be mhp_params as it is a list of
extended parameters.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Badger <ebadger@gigaio.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200306170846.9333-3-logang@deltatee.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are many places where all basic VMA access flags (read, write,
exec) are initialized or checked against as a group. One such example
is during page fault. Existing vma_is_accessible() wrapper already
creates the notion of VMA accessibility as a group access permissions.
Hence lets just create VM_ACCESS_FLAGS (VM_READ|VM_WRITE|VM_EXEC) which
will not only reduce code duplication but also extend the VMA
accessibility concept in general.
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Springer <rspringer@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Link: http://lkml.kernel.org/r/1583391014-8170-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Add support for region alignment configuration and enforcement to
fix compatibility across architectures and PowerPC page size
configurations.
- Introduce 'zero_page_range' as a dax operation. This facilitates
filesystem-dax operation without a block-device.
- Introduce phys_to_target_node() to facilitate drivers that want to
know resulting numa node if a given reserved address range was
onlined.
- Advertise a persistence-domain for of_pmem and papr_scm. The
persistence domain indicates where cpu-store cycles need to reach in
the platform-memory subsystem before the platform will consider them
power-fail protected.
- Promote numa_map_to_online_node() to a cross-kernel generic facility.
- Save x86 numa information to allow for node-id lookups for reserved
memory ranges, deploy that capability for the e820-pmem driver.
- Pick up some miscellaneous minor fixes, that missed v5.6-final,
including a some smatch reports in the ioctl path and some unit test
compilation fixups.
- Fixup some flexible-array declarations.
-----BEGIN PGP SIGNATURE-----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=sY4N
-----END PGP SIGNATURE-----
Merge tag 'libnvdimm-for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm and dax updates from Dan Williams:
"There were multiple touches outside of drivers/nvdimm/ this round to
add cross arch compatibility to the devm_memremap_pages() interface,
enhance numa information for persistent memory ranges, and add a
zero_page_range() dax operation.
This cycle I switched from the patchwork api to Konstantin's b4 script
for collecting tags (from x86, PowerPC, filesystem, and device-mapper
folks), and everything looks to have gone ok there. This has all
appeared in -next with no reported issues.
Summary:
- Add support for region alignment configuration and enforcement to
fix compatibility across architectures and PowerPC page size
configurations.
- Introduce 'zero_page_range' as a dax operation. This facilitates
filesystem-dax operation without a block-device.
- Introduce phys_to_target_node() to facilitate drivers that want to
know resulting numa node if a given reserved address range was
onlined.
- Advertise a persistence-domain for of_pmem and papr_scm. The
persistence domain indicates where cpu-store cycles need to reach
in the platform-memory subsystem before the platform will consider
them power-fail protected.
- Promote numa_map_to_online_node() to a cross-kernel generic
facility.
- Save x86 numa information to allow for node-id lookups for reserved
memory ranges, deploy that capability for the e820-pmem driver.
- Pick up some miscellaneous minor fixes, that missed v5.6-final,
including a some smatch reports in the ioctl path and some unit
test compilation fixups.
- Fixup some flexible-array declarations"
* tag 'libnvdimm-for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (29 commits)
dax: Move mandatory ->zero_page_range() check in alloc_dax()
dax,iomap: Add helper dax_iomap_zero() to zero a range
dax: Use new dax zero page method for zeroing a page
dm,dax: Add dax zero_page_range operation
s390,dcssblk,dax: Add dax zero_page_range operation to dcssblk driver
dax, pmem: Add a dax operation zero_page_range
pmem: Add functions for reading/writing page to/from pmem
libnvdimm: Update persistence domain value for of_pmem and papr_scm device
tools/test/nvdimm: Fix out of tree build
libnvdimm/region: Fix build error
libnvdimm/region: Replace zero-length array with flexible-array member
libnvdimm/label: Replace zero-length array with flexible-array member
ACPI: NFIT: Replace zero-length array with flexible-array member
libnvdimm/region: Introduce an 'align' attribute
libnvdimm/region: Introduce NDD_LABELING
libnvdimm/namespace: Enforce memremap_compat_align()
libnvdimm/pfn: Prevent raw mode fallback if pfn-infoblock valid
libnvdimm: Out of bounds read in __nd_ioctl()
acpi/nfit: improve bounds checking for 'func'
mm/memremap_pages: Introduce memremap_compat_align()
...
- A large series from Nick for 64-bit to further rework our exception vectors,
and rewrite portions of the syscall entry/exit and interrupt return in C. The
result is much easier to follow code that is also faster in general.
- Cleanup of our ptrace code to split various parts out that had become badly
intertwined with #ifdefs over the years.
- Changes to our NUMA setup under the PowerVM hypervisor which should
hopefully avoid non-sensical topologies which can lead to warnings from the
workqueue code and other problems.
- MAINTAINERS updates to remove some of our old orphan entries and update the
status of others.
- Quite a few other small changes and fixes all over the map.
Thanks to:
Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew Donnellan, Aneesh
Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen Zhou, Christophe JAILLET,
Christophe Leroy, Christoph Hellwig, Clement Courbet, Daniel Axtens, David
Gibson, Douglas Miller, Fabiano Rosas, Fangrui Song, Ganesh Goudar, Gautham R.
Shenoy, Greg Kroah-Hartman, Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie
Halip, Jan Kara, Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger,
Laurentiu Tudor, Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh
Salgaonkar, Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira,
Michael Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan
Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers,
Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat, Rasmus Villemoes, Ravi
Bangoria, Roman Bolshakov, Sam Bobroff, Sandipan Das, Santosh S, Sedat Dilek,
Segher Boessenkool, Shilpasri G Bhat, Sourabh Jain, Srikar Dronamraju, Stephen
Rothwell, Tyrel Datwyler, Vaibhav Jain, YueHaibing.
-----BEGIN PGP SIGNATURE-----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=ARdm
-----END PGP SIGNATURE-----
Merge tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Slightly late as I had to rebase mid-week to insert a bug fix:
- A large series from Nick for 64-bit to further rework our exception
vectors, and rewrite portions of the syscall entry/exit and
interrupt return in C. The result is much easier to follow code
that is also faster in general.
- Cleanup of our ptrace code to split various parts out that had
become badly intertwined with #ifdefs over the years.
- Changes to our NUMA setup under the PowerVM hypervisor which should
hopefully avoid non-sensical topologies which can lead to warnings
from the workqueue code and other problems.
- MAINTAINERS updates to remove some of our old orphan entries and
update the status of others.
- Quite a few other small changes and fixes all over the map.
Thanks to: Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew
Donnellan, Aneesh Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen
Zhou, Christophe JAILLET, Christophe Leroy, Christoph Hellwig, Clement
Courbet, Daniel Axtens, David Gibson, Douglas Miller, Fabiano Rosas,
Fangrui Song, Ganesh Goudar, Gautham R. Shenoy, Greg Kroah-Hartman,
Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie Halip, Jan Kara,
Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger, Laurentiu Tudor,
Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh Salgaonkar,
Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira, Michael
Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan
Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick
Desaulniers, Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat,
Rasmus Villemoes, Ravi Bangoria, Roman Bolshakov, Sam Bobroff,
Sandipan Das, Santosh S, Sedat Dilek, Segher Boessenkool, Shilpasri G
Bhat, Sourabh Jain, Srikar Dronamraju, Stephen Rothwell, Tyrel
Datwyler, Vaibhav Jain, YueHaibing"
* tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits)
powerpc: Make setjmp/longjmp signature standard
powerpc/cputable: Remove unnecessary copy of cpu_spec->oprofile_type
powerpc: Suppress .eh_frame generation
powerpc: Drop -fno-dwarf2-cfi-asm
powerpc/32: drop unused ISA_DMA_THRESHOLD
powerpc/powernv: Add documentation for the opal sensor_groups sysfs interfaces
selftests/powerpc: Fix try-run when source tree is not writable
powerpc/vmlinux.lds: Explicitly retain .gnu.hash
powerpc/ptrace: move ptrace_triggered() into hw_breakpoint.c
powerpc/ptrace: create ppc_gethwdinfo()
powerpc/ptrace: create ptrace_get_debugreg()
powerpc/ptrace: split out ADV_DEBUG_REGS related functions.
powerpc/ptrace: move register viewing functions out of ptrace.c
powerpc/ptrace: split out TRANSACTIONAL_MEM related functions.
powerpc/ptrace: split out SPE related functions.
powerpc/ptrace: split out ALTIVEC related functions.
powerpc/ptrace: split out VSX related functions.
powerpc/ptrace: drop PARAMETER_SAVE_AREA_OFFSET
powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64
powerpc/ptrace: remove unused header includes
...
The idea comes from a discussion between Linus and Andrea [1].
Before this patch we only allow a page fault to retry once. We achieved
this by clearing the FAULT_FLAG_ALLOW_RETRY flag when doing
handle_mm_fault() the second time. This was majorly used to avoid
unexpected starvation of the system by looping over forever to handle the
page fault on a single page. However that should hardly happen, and after
all for each code path to return a VM_FAULT_RETRY we'll first wait for a
condition (during which time we should possibly yield the cpu) to happen
before VM_FAULT_RETRY is really returned.
This patch removes the restriction by keeping the FAULT_FLAG_ALLOW_RETRY
flag when we receive VM_FAULT_RETRY. It means that the page fault handler
now can retry the page fault for multiple times if necessary without the
need to generate another page fault event. Meanwhile we still keep the
FAULT_FLAG_TRIED flag so page fault handler can still identify whether a
page fault is the first attempt or not.
Then we'll have these combinations of fault flags (only considering
ALLOW_RETRY flag and TRIED flag):
- ALLOW_RETRY and !TRIED: this means the page fault allows to
retry, and this is the first try
- ALLOW_RETRY and TRIED: this means the page fault allows to
retry, and this is not the first try
- !ALLOW_RETRY and !TRIED: this means the page fault does not allow
to retry at all
- !ALLOW_RETRY and TRIED: this is forbidden and should never be used
In existing code we have multiple places that has taken special care of
the first condition above by checking against (fault_flags &
FAULT_FLAG_ALLOW_RETRY). This patch introduces a simple helper to detect
the first retry of a page fault by checking against both (fault_flags &
FAULT_FLAG_ALLOW_RETRY) and !(fault_flag & FAULT_FLAG_TRIED) because now
even the 2nd try will have the ALLOW_RETRY set, then use that helper in
all existing special paths. One example is in __lock_page_or_retry(), now
we'll drop the mmap_sem only in the first attempt of page fault and we'll
keep it in follow up retries, so old locking behavior will be retained.
This will be a nice enhancement for current code [2] at the same time a
supporting material for the future userfaultfd-writeprotect work, since in
that work there will always be an explicit userfault writeprotect retry
for protected pages, and if that cannot resolve the page fault (e.g., when
userfaultfd-writeprotect is used in conjunction with swapped pages) then
we'll possibly need a 3rd retry of the page fault. It might also benefit
other potential users who will have similar requirement like userfault
write-protection.
GUP code is not touched yet and will be covered in follow up patch.
Please read the thread below for more information.
[1] https://lore.kernel.org/lkml/20171102193644.GB22686@redhat.com/
[2] https://lore.kernel.org/lkml/20181230154648.GB9832@redhat.com/
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220160246.9790-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Although there're tons of arch-specific page fault handlers, most of them
are still sharing the same initial value of the page fault flags. Say,
merely all of the page fault handlers would allow the fault to be retried,
and they also allow the fault to respond to SIGKILL.
Let's define a default value for the fault flags to replace those initial
page fault flags that were copied over. With this, it'll be far easier to
introduce new fault flag that can be used by all the architectures instead
of touching all the archs.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220160238.9694-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Let powerpc code to use the new helper, by moving the signal handling
earlier before the retry logic.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220160222.9422-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Idea of a foreign VMA with respect to the present context is very generic.
But currently there are two identical definitions for this in powerpc and
x86 platforms. Lets consolidate those redundant definitions while making
vma_is_foreign() available for general use later. This should not cause
any functional change.
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Link: http://lkml.kernel.org/r/1582782965-3274-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reorder Linux PTE bits to (almost) match Hash PTE bits.
RW Kernel : PP = 00
RO Kernel : PP = 00
RW User : PP = 01
RO User : PP = 11
So naturally, we should have
_PAGE_USER = 0x001
_PAGE_RW = 0x002
Today 0x001 and 0x002 and _PAGE_PRESENT and _PAGE_HASHPTE which
both are software only bits.
Switch _PAGE_USER and _PAGE_PRESET
Switch _PAGE_RW and _PAGE_HASHPTE
This allows to remove a few insns.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c4d6c18a7f8d9d3b899bc492f55fbc40ef38896a.1583861325.git.christophe.leroy@c-s.fr
In the current implementation, the call to loadcam_multi() is wrapped
between switch_to_as1() and restore_to_as0() calls so, when it tries
to create its own temporary AS=1 TLB1 entry, it ends up duplicating
the existing one created by switch_to_as1(). Add a check to skip
creating the temporary entry if already running in AS=1.
Fixes: d9e1831a42 ("powerpc/85xx: Load all early TLB entries at once")
Cc: stable@vger.kernel.org # v4.4+
Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Acked-by: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200123111914.2565-1-laurentiu.tudor@nxp.com
With CONFIG_KASAN_VMALLOC, new page tables are created at the time
shadow memory for vmalloc area is unmapped. If some parts of the
page table still have entries to the zero page shadow memory, the
entries are wrongly marked RW.
With CONFIG_KASAN_VMALLOC, almost the entire kernel address space
is managed by KASAN. To make it simple, just create KASAN page tables
for the entire kernel space at kasan_init(). That doesn't use much
more space, and that's anyway already done for hash platforms.
Fixes: 3d4247fcc9 ("powerpc/32: Add support of KASAN_VMALLOC")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ef5248fc1f496c6b0dfdb59380f24968f25f75c5.1583513368.git.christophe.leroy@c-s.fr
Stefan reported a strange kernel fault which turned out to be due to a
missing KUAP disable in flush_coherent_icache() called from
flush_icache_range().
The fault looks like:
Kernel attempted to access user page (7fffc30d9c00) - exploit attempt? (uid: 1009)
BUG: Unable to handle kernel data access on read at 0x7fffc30d9c00
Faulting instruction address: 0xc00000000007232c
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV
CPU: 35 PID: 5886 Comm: sigtramp Not tainted 5.6.0-rc2-gcc-8.2.0-00003-gfc37a1632d40 #79
NIP: c00000000007232c LR: c00000000003b7fc CTR: 0000000000000000
REGS: c000001e11093940 TRAP: 0300 Not tainted (5.6.0-rc2-gcc-8.2.0-00003-gfc37a1632d40)
MSR: 900000000280b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 28000884 XER: 00000000
CFAR: c0000000000722fc DAR: 00007fffc30d9c00 DSISR: 08000000 IRQMASK: 0
GPR00: c00000000003b7fc c000001e11093bd0 c0000000023ac200 00007fffc30d9c00
GPR04: 00007fffc30d9c18 0000000000000000 c000001e11093bd4 0000000000000000
GPR08: 0000000000000000 0000000000000001 0000000000000000 c000001e1104ed80
GPR12: 0000000000000000 c000001fff6ab380 c0000000016be2d0 4000000000000000
GPR16: c000000000000000 bfffffffffffffff 0000000000000000 0000000000000000
GPR20: 00007fffc30d9c00 00007fffc30d8f58 00007fffc30d9c18 00007fffc30d9c20
GPR24: 00007fffc30d9c18 0000000000000000 c000001e11093d90 c000001e1104ed80
GPR28: c000001e11093e90 0000000000000000 c0000000023d9d18 00007fffc30d9c00
NIP flush_icache_range+0x5c/0x80
LR handle_rt_signal64+0x95c/0xc2c
Call Trace:
0xc000001e11093d90 (unreliable)
handle_rt_signal64+0x93c/0xc2c
do_notify_resume+0x310/0x430
ret_from_except_lite+0x70/0x74
Instruction dump:
409e002c 7c0802a6 3c62ff31 3863f6a0 f8010080 48195fed 60000000 48fe4c8d
60000000 e8010080 7c0803a6 7c0004ac <7c00ffac> 7c0004ac 4c00012c 38210070
This path through handle_rt_signal64() to setup_trampoline() and
flush_icache_range() is only triggered by 64-bit processes that have
unmapped their VDSO, which is rare.
flush_icache_range() takes a range of addresses to flush. In
flush_coherent_icache() we implement an optimisation for CPUs where we
know we don't actually have to flush the whole range, we just need to
do a single icbi.
However we still execute the icbi on the user address of the start of
the range we're flushing. On CPUs that also implement KUAP (Power9)
that leads to the spurious fault above.
We should be able to pass any address, including a kernel address, to
the icbi on these CPUs, which would avoid any interaction with KUAP.
But I don't want to make that change in a bug fix, just in case it
surfaces some strange behaviour on some CPU.
So for now just disable KUAP around the icbi. Note the icbi is treated
as a load, so we allow read access, not write as you'd expect.
Fixes: 890274c2dc ("powerpc/64s: Implement KUAP for Radix MMU")
Cc: stable@vger.kernel.org # v5.2+
Reported-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200303235708.26004-1-mpe@ellerman.id.au
With commit ("powerpc/numa: Early request for home node associativity"),
commit 2ea6263068 ("powerpc/topology: Get topology for shared
processors at boot") which was requesting home node associativity
becomes redundant.
Hence remove the late request for home node associativity.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200129135301.24739-6-srikar@linux.vnet.ibm.com
Currently the kernel detects if its running on a shared lpar platform
and requests home node associativity before the scheduler sched_domains
are setup. However between the time NUMA setup is initialized and the
request for home node associativity, workqueue initializes its per node
cpumask. The per node workqueue possible cpumask may turn invalid
after home node associativity resulting in weird situations like
workqueue possible cpumask being a subset of workqueue online cpumask.
This can be fixed by requesting home node associativity earlier just
before NUMA setup. However at the NUMA setup time, kernel may not be in
a position to detect if its running on a shared lpar platform. So
request for home node associativity and if the request fails, fallback
on the device tree property.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200129135301.24739-5-srikar@linux.vnet.ibm.com
All the sibling threads of a core have to be part of the same node.
To ensure that all the sibling threads map to the same node, always
lookup/update the cpu-to-node map of the first thread in the core.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200129135301.24739-4-srikar@linux.vnet.ibm.com
Currently code handles H_FUNCTION, H_SUCCESS, H_HARDWARE return codes.
However hcall_vphn can return other return codes. Now it also handles
H_PARAMETER return code. Also the rest return codes are handled under the
default case.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200129135301.24739-3-srikar@linux.vnet.ibm.com
The last jump to free_exit in mm_iommu_do_alloc() happens after page
pointers in struct mm_iommu_table_group_mem_t were already converted to
physical addresses. Thus calling put_page() on these physical addresses
will likely crash.
This moves the loop which calculates the pageshift and converts page
struct pointers to physical addresses later after the point when
we cannot fail; thus eliminating the need to convert pointers back.
Fixes: eb9d7a62c3 ("powerpc/mm_iommu: Fix potential deadlock")
Reported-by: Jan Kara <jack@suse.cz>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191223060351.26359-1-aik@ozlabs.ru
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200209105901.1620958-4-gregkh@linuxfoundation.org
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200209105901.1620958-3-gregkh@linuxfoundation.org
Commit 8d30c14cab ("powerpc/mm: Rework I$/D$ coherency (v3)") and
commit 90ac19a8b2 ("[POWERPC] Abolish iopa(), mm_ptov(),
io_block_mapping() from arch/powerpc") removed the use of get_pteptr()
outside of mm/pgtable_32.c
In mm/pgtable_32.c, the only user of get_pteptr() is change_page_attr()
which operates on kernel context and on lowmem pages only.
Make virt_to_kpte() available outside of mm/mem.c and use it instead
of get_pteptr(), and drop get_pteptr()
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/788378c6c3ba5c5298caab7c7f95e6c3c88244b8.1578558199.git.christophe.leroy@c-s.fr
At several places pmd pointer is retrieved through the same action:
pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr);
or
pmd = pmd_offset(pud_offset(pgd_offset_k(addr), addr), addr);
Refactor this by implementing two helpers pmd_ptr() and pmd_ptr_k()
This will help when adding the p4d level.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7b065c5be35726af4066cab238ee35cabceda1fa.1578558199.git.christophe.leroy@c-s.fr
The "sub-section memory hotplug" facility allows memremap_pages() users
like libnvdimm to compensate for hardware platforms like x86 that have a
section size larger than their hardware memory mapping granularity. The
compensation that sub-section support affords is being tolerant of
physical memory resources shifting by units smaller (64MiB on x86) than
the memory-hotplug section size (128 MiB). Where the platform
physical-memory mapping granularity is limited by the number and
capability of address-decode-registers in the memory controller.
While the sub-section support allows memremap_pages() to operate on
sub-section (2MiB) granularity, the Power architecture may still
require 16MiB alignment on "!radix_enabled()" platforms.
In order for libnvdimm to be able to detect and manage this per-arch
limitation, introduce memremap_compat_align() as a common minimum
alignment across all driver-facing memory-mapping interfaces, and let
Power override it to 16MiB in the "!radix_enabled()" case.
The assumption / requirement for 16MiB to be a viable
memremap_compat_align() value is that Power does not have platforms
where its equivalent of address-decode-registers never hardware remaps a
persistent memory resource on smaller than 16MiB boundaries. Note that I
tried my best to not add a new Kconfig symbol, but header include
entanglements defeated the #ifndef memremap_compat_align design pattern
and the need to export it defeats the __weak design pattern for arch
overrides.
Based on an initial patch by Aneesh.
Link: http://lore.kernel.org/r/CAPcyv4gBGNP95APYaBcsocEa50tQj9b5h__83vgngjq3ouGX_Q@mail.gmail.com
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reported-by: Jeff Moyer <jmoyer@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
_tlbia() is a function used only on 603/603e core, ie on CPUs which
don't have a hash table.
_tlbia() uses the tlbia macro which implements a loop of 1024 tlbie.
On the 603/603e core, flushing the entire TLB requires no more than
32 tlbie.
Replace tlbia by a loop of 32 tlbie.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/12f4f4f0ff89aeab3b937fc96c84fb35e1b2517e.1580748445.git.christophe.leroy@c-s.fr
When flushing any memory range, the flushing function
flushes all TLBs.
When (start) and (end - 1) are in the same memory page,
flush that page instead.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b30b2eae6960502eaf0d9e36c60820b839693c33.1580542939.git.christophe.leroy@c-s.fr
hash_page() needs to read page tables from kernel memory. When entire
kernel memory is mapped by BATs, which is normally the case when
CONFIG_STRICT_KERNEL_RWX is not set, it works even if the page hosting
the page table is not referenced in the MMU hash table.
However, if the page where the page table resides is not covered by
a BAT, a DSI fault can be encountered from hash_page(), and it loops
forever. This can happen when CONFIG_STRICT_KERNEL_RWX is selected
and the alignment of the different regions is too small to allow
covering the entire memory with BATs. This also happens when
CONFIG_DEBUG_PAGEALLOC is selected or when booting with 'nobats'
flag.
Also, if the page containing the kernel stack is not present in the
MMU hash table, registers cannot be saved and a recursive DSI fault
is encountered.
To allow hash_page() to properly do its job at all time and load the
MMU hash table whenever needed, it must run with data MMU disabled.
This means it must be called before re-enabling data MMU. To allow
this, registers clobbered by hash_page() and create_hpte() have to
be saved in the thread struct together with SRR0, SSR1, DAR and DSISR.
It is also necessary to ensure that DSI prolog doesn't overwrite
regs saved by prolog of the current running exception. That means:
- DSI can only use SPRN_SPRG_SCRATCH0
- Exceptions must free SPRN_SPRG_SCRATCH0 before writing to the stack.
This also fixes the Oops reported by Erhard when create_hpte() is
called by add_hash_page().
Due to prolog size increase, a few more exceptions had to get split
in two parts.
Fixes: cd08f109e2 ("powerpc/32s: Enable CONFIG_VMAP_STACK")
Reported-by: Erhard F. <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Tested-by: Erhard F. <erhard_f@mailbox.org>
Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206501
Link: https://lore.kernel.org/r/64a4aa44686e9fd4b01333401367029771d9b231.1581761633.git.christophe.leroy@c-s.fr
Commit 55c8fc3f49 ("powerpc/8xx: reintroduce 16K pages with HW
assistance") redefined pte_t as a struct of 4 pte_basic_t, because
in 16K pages mode there are four identical entries in the
page table. But the size of hugepage tables is calculated based
of the size of (void *). Therefore, we end up with page tables
of size 1k instead of 4k for 512k pages.
As 512k hugepage tables are the same size as standard page tables,
ie 4k, use the standard page tables instead of PGT_CACHE tables.
Fixes: 3fb69c6a1a ("powerpc/8xx: Enable 512k hugepage support with HW assistance")
Cc: stable@vger.kernel.org # v5.0+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/90ec56a2315be602494619ed0223bba3b0b8d619.1580997007.git.christophe.leroy@c-s.fr
- Implement user_access_begin() and friends for our platforms that support
controlling kernel access to userspace.
- Enable CONFIG_VMAP_STACK on 32-bit Book3S and 8xx.
- Some tweaks to our pseries IOMMU code to allow SVMs ("secure" virtual
machines) to use the IOMMU.
- Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 32-bit VDSO, and
some other improvements.
- A series to use the PCI hotplug framework to control opencapi card's so that
they can be reset and re-read after flashing a new FPGA image.
As well as other minor fixes and improvements as usual.
Thanks to:
Alastair D'Silva, Alexandre Ghiti, Alexey Kardashevskiy, Andrew Donnellan,
Aneesh Kumar K.V, Anju T Sudhakar, Bai Yingjie, Chen Zhou, Christophe Leroy,
Frederic Barrat, Greg Kurz, Jason A. Donenfeld, Joel Stanley, Jordan Niethe,
Julia Lawall, Krzysztof Kozlowski, Laurent Dufour, Laurentiu Tudor, Linus
Walleij, Michael Bringmann, Nathan Chancellor, Nicholas Piggin, Nick
Desaulniers, Oliver O'Halloran, Peter Ujfalusi, Pingfan Liu, Ram Pai, Randy
Dunlap, Russell Currey, Sam Bobroff, Sebastian Andrzej Siewior, Shawn
Anastasio, Stephen Rothwell, Steve Best, Sukadev Bhattiprolu, Thiago Jung
Bauermann, Tyrel Datwyler, Vaibhav Jain.
-----BEGIN PGP SIGNATURE-----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=xpG+
-----END PGP SIGNATURE-----
Merge tag 'powerpc-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"A pretty small batch for us, and apologies for it being a bit late, I
wanted to sneak Christophe's user_access_begin() series in.
Summary:
- Implement user_access_begin() and friends for our platforms that
support controlling kernel access to userspace.
- Enable CONFIG_VMAP_STACK on 32-bit Book3S and 8xx.
- Some tweaks to our pseries IOMMU code to allow SVMs ("secure"
virtual machines) to use the IOMMU.
- Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 32-bit
VDSO, and some other improvements.
- A series to use the PCI hotplug framework to control opencapi
card's so that they can be reset and re-read after flashing a new
FPGA image.
As well as other minor fixes and improvements as usual.
Thanks to: Alastair D'Silva, Alexandre Ghiti, Alexey Kardashevskiy,
Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Bai Yingjie, Chen
Zhou, Christophe Leroy, Frederic Barrat, Greg Kurz, Jason A.
Donenfeld, Joel Stanley, Jordan Niethe, Julia Lawall, Krzysztof
Kozlowski, Laurent Dufour, Laurentiu Tudor, Linus Walleij, Michael
Bringmann, Nathan Chancellor, Nicholas Piggin, Nick Desaulniers,
Oliver O'Halloran, Peter Ujfalusi, Pingfan Liu, Ram Pai, Randy Dunlap,
Russell Currey, Sam Bobroff, Sebastian Andrzej Siewior, Shawn
Anastasio, Stephen Rothwell, Steve Best, Sukadev Bhattiprolu, Thiago
Jung Bauermann, Tyrel Datwyler, Vaibhav Jain"
* tag 'powerpc-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (131 commits)
powerpc: configs: Cleanup old Kconfig options
powerpc/configs/skiroot: Enable some more hardening options
powerpc/configs/skiroot: Disable xmon default & enable reboot on panic
powerpc/configs/skiroot: Enable security features
powerpc/configs/skiroot: Update for symbol movement only
powerpc/configs/skiroot: Drop default n CONFIG_CRYPTO_ECHAINIV
powerpc/configs/skiroot: Drop HID_LOGITECH
powerpc/configs: Drop NET_VENDOR_HP which moved to staging
powerpc/configs: NET_CADENCE became NET_VENDOR_CADENCE
powerpc/configs: Drop CONFIG_QLGE which moved to staging
powerpc: Do not consider weak unresolved symbol relocations as bad
powerpc/32s: Fix kasan_early_hash_table() for CONFIG_VMAP_STACK
powerpc: indent to improve Kconfig readability
powerpc: Provide initial documentation for PAPR hcalls
powerpc: Implement user_access_save() and user_access_restore()
powerpc: Implement user_access_begin and friends
powerpc/32s: Prepare prevent_user_access() for user_access_end()
powerpc/32s: Drop NULL addr verification
powerpc/kuap: Fix set direction in allow/prevent_user_access()
powerpc/32s: Fix bad_kuap_fault()
...
Patch series "Fixup page directory freeing", v4.
This is a repost of patch series from Peter with the arch specific changes
except ppc64 dropped. ppc64 changes are added here because we are redoing
the patch series on top of ppc64 changes. This makes it easy to backport
these changes. Only the first 2 patches need to be backported to stable.
The thing is, on anything SMP, freeing page directories should observe the
exact same order as normal page freeing:
1) unhook page/directory
2) TLB invalidate
3) free page/directory
Without this, any concurrent page-table walk could end up with a
Use-after-Free. This is esp. trivial for anything that has software
page-table walkers (HAVE_FAST_GUP / software TLB fill) or the hardware
caches partial page-walks (ie. caches page directories).
Even on UP this might give issues since mmu_gather is preemptible these
days. An interrupt or preempted task accessing user pages might stumble
into the free page if the hardware caches page directories.
This patch series fixes ppc64 and add generic MMU_GATHER changes to
support the conversion of other architectures. I haven't added patches
w.r.t other architecture because they are yet to be acked.
This patch (of 9):
A followup patch is going to make sure we correctly invalidate page walk
cache before we free page table pages. In order to keep things simple
enable RCU_TABLE_FREE even for !SMP so that we don't have to fixup the
!SMP case differently in the followup patch
!SMP case is right now broken for radix translation w.r.t page walk
cache flush. We can get interrupted in between page table free and
that would imply we have page walk cache entries pointing to tables
which got freed already. Michael said "both our platforms that run on
Power9 force SMP on in Kconfig, so the !SMP case is unlikely to be a
problem for anyone in practice, unless they've hacked their kernel to
build it !SMP."
Link: http://lkml.kernel.org/r/20200116064531.483522-2-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In order to provide a clearer, more symmetric API for pinning and
unpinning DMA pages. This way, pin_user_pages*() calls match up with
unpin_user_pages*() calls, and the API is a lot closer to being
self-explanatory.
Link: http://lkml.kernel.org/r/20200107224558.2362728-23-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1. Convert from get_user_pages() to pin_user_pages().
2. As required by pin_user_pages(), release these pages via
put_user_page().
Link: http://lkml.kernel.org/r/20200107224558.2362728-21-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On book3s/32 CPUs that are handling MMU through a hash table,
MMU_init_hw() function was adapted for VMAP_STACK in order to
handle virtual addresses instead of physical addresses in the
low level hash functions.
When using KASAN, the same adaptations are required for the
early hash table set up by kasan_early_hash_table() function.
Fixes: cd08f109e2 ("powerpc/32s: Enable CONFIG_VMAP_STACK")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fc8390a33c2a470105f01abbcbdc7916c30c0a54.1580301269.git.christophe.leroy@c-s.fr
At the moment, bad_kuap_fault() reports a fault only if a bad access
to userspace occurred while access to userspace was not granted.
But if a fault occurs for a write outside the allowed userspace
segment(s) that have been unlocked, bad_kuap_fault() fails to
detect it and the kernel loops forever in do_page_fault().
Fix it by checking that the accessed address is within the allowed
range.
Fixes: a68c31fc01 ("powerpc/32s: Implement Kernel Userspace Access Protection")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f48244e9485ada0a304ed33ccbb8da271180c80d.1579866752.git.christophe.leroy@c-s.fr
Add support of KASAN_VMALLOC on PPC32.
To allow this, the early shadow covering the VMALLOC space
need to be removed once high_memory var is set and before
freeing memblock.
And the VMALLOC area need to be aligned such that boundaries
are covered by a full shadow page.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/031dec5487bde9b2181c8b3c9800e1879cf98c1a.1579024426.git.christophe.leroy@c-s.fr
Running vdsotest leaves many times the following log:
[ 79.629901] vdsotest[396]: User access of kernel address (ffffffff) - exploit attempt? (uid: 0)
A pointer set to (-1) is likely a programming error similar to
a NULL pointer and is not worth logging as an exploit attempt.
Don't log user accesses to 0xffffffff.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0728849e826ba16f1fbd6fa7f5c6cc87bd64e097.1577087627.git.christophe.leroy@c-s.fr
A few changes to retrieve DAR and DSISR from struct regs
instead of retrieving them directly, as they may have
changed due to a TLB miss.
Also modifies hash_page() and friends to work with virtual
data addresses instead of physical ones. Same on load_up_fpu()
and load_up_altivec().
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Fix tovirt_vmstack call in head_32.S to fix CHRP build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2e2509a242fd5f3e23df4a06530c18060c4d321e.1576916812.git.christophe.leroy@c-s.fr
Commit a25bd72bad ("powerpc/mm/radix: Workaround prefetch issue with
KVM") introduced a number of workarounds as coming out of a guest with
the mmu enabled would make the cpu would start running in hypervisor
state with the PID value from the guest. The cpu will then start
prefetching for the hypervisor with that PID value.
In Power9 DD2.2 the cpu behaviour was modified to fix this. When
accessing Quadrant 0 in hypervisor mode with LPID != 0 prefetching will
not be performed. This means that we can get rid of the workarounds for
Power9 DD2.2 and later revisions. Add a new cpu feature
CPU_FTR_P9_RADIX_PREFETCH_BUG to indicate if the workarounds are needed.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191206031722.25781-1-jniethe5@gmail.com
Verification cannot rely on simple bit checking because on some
platforms PAGE_RW is 0, checking that a page is not W means
checking that PAGE_RO is set instead of checking that PAGE_RW
is not set.
Use pte helpers instead of checking bits.
Fixes: 453d87f6a8 ("powerpc/mm: Warn if W+X pages found on boot")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0d894839fdbb19070f0e1e4140363be4f2bb62fc.1578989540.git.christophe.leroy@c-s.fr
Selecting CONFIG_PPC_DEBUG_WX only impacts ptdump and pgtable_32/64
init calls. Declaring related functions in asm/pgtable.h implies
rebuilding almost everything.
Move ptdump_check_wx() declaration in mm/mmu_decl.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/bf34fd9dca61eadf9a134a9f89ebbc162cfd5f86.1578986011.git.christophe.leroy@c-s.fr
With STRICT_KERNEL_RWX on in a relocatable kernel under the hash MMU,
if the position the kernel is loaded at is not 16M aligned things go
horribly wrong. Specifically hash__mark_initmem_nx() will call
hash__change_memory_range() which then aligns down the start address,
and due to the text not being 16M aligned causes some of the kernel
text to be marked non-executable.
We can avoid this when selecting the linear mapping size, so do so and
print a warning. I tested this for various alignments and as long as
the position is 64K aligned it's fine (the base requirement for
powerpc).
Signed-off-by: Russell Currey <ruscur@russell.cc>
[mpe: Add details of the failure mode]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191224064126.183670-1-ruscur@russell.cc
We currently try to shrink a single zone when removing memory. We use
the zone of the first page of the memory we are removing. If that
memmap was never initialized (e.g., memory was never onlined), we will
read garbage and can trigger kernel BUGs (due to a stale pointer):
BUG: unable to handle page fault for address: 000000000000353d
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#1] SMP PTI
CPU: 1 PID: 7 Comm: kworker/u8:0 Not tainted 5.3.0-rc5-next-20190820+ #317
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.4
Workqueue: kacpi_hotplug acpi_hotplug_work_fn
RIP: 0010:clear_zone_contiguous+0x5/0x10
Code: 48 89 c6 48 89 c3 e8 2a fe ff ff 48 85 c0 75 cf 5b 5d c3 c6 85 fd 05 00 00 01 5b 5d c3 0f 1f 840
RSP: 0018:ffffad2400043c98 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000200000000 RCX: 0000000000000000
RDX: 0000000000200000 RSI: 0000000000140000 RDI: 0000000000002f40
RBP: 0000000140000000 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000140000
R13: 0000000000140000 R14: 0000000000002f40 R15: ffff9e3e7aff3680
FS: 0000000000000000(0000) GS:ffff9e3e7bb00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000353d CR3: 0000000058610000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__remove_pages+0x4b/0x640
arch_remove_memory+0x63/0x8d
try_remove_memory+0xdb/0x130
__remove_memory+0xa/0x11
acpi_memory_device_remove+0x70/0x100
acpi_bus_trim+0x55/0x90
acpi_device_hotplug+0x227/0x3a0
acpi_hotplug_work_fn+0x1a/0x30
process_one_work+0x221/0x550
worker_thread+0x50/0x3b0
kthread+0x105/0x140
ret_from_fork+0x3a/0x50
Modules linked in:
CR2: 000000000000353d
Instead, shrink the zones when offlining memory or when onlining failed.
Introduce and use remove_pfn_range_from_zone(() for that. We now
properly shrink the zones, even if we have DIMMs whereby
- Some memory blocks fall into no zone (never onlined)
- Some memory blocks fall into multiple zones (offlined+re-onlined)
- Multiple memory blocks that fall into different zones
Drop the zone parameter (with a potential dubious value) from
__remove_pages() and __remove_section().
Link: http://lkml.kernel.org/r/20191006085646.5768-6-david@redhat.com
Fixes: f1dd2cd13c ("mm, memory_hotplug: do not associate hotadded memory to zones until online") [visible after d0dc12e86b]
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: <stable@vger.kernel.org> [5.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These slice routines are called from the SLB miss handler, which can
lead to warnings from the IRQ code, because we have not reconciled the
IRQ state properly:
WARNING: CPU: 72 PID: 30150 at arch/powerpc/kernel/irq.c:258 arch_local_irq_restore.part.0+0xcc/0x100
Modules linked in:
CPU: 72 PID: 30150 Comm: ftracetest Not tainted 5.5.0-rc2-gcc9x-g7e0165b2f1a9 #1
NIP: c00000000001d83c LR: c00000000029ab90 CTR: c00000000026cf90
REGS: c0000007eee3b960 TRAP: 0700 Not tainted (5.5.0-rc2-gcc9x-g7e0165b2f1a9)
MSR: 8000000000021033 <SF,ME,IR,DR,RI,LE> CR: 22242844 XER: 20000000
CFAR: c00000000001d780 IRQMASK: 0
...
NIP arch_local_irq_restore.part.0+0xcc/0x100
LR trace_graph_entry+0x270/0x340
Call Trace:
trace_graph_entry+0x254/0x340 (unreliable)
function_graph_enter+0xe4/0x1a0
prepare_ftrace_return+0xa0/0x130
ftrace_graph_caller+0x44/0x94 # (get_slice_psize())
slb_allocate_user+0x7c/0x100
do_slb_fault+0xf8/0x300
instruction_access_slb_common+0x140/0x180
Fixes: 48e7b76957 ("powerpc/64s/hash: Convert SLB miss handlers to C")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191221121337.4894-1-mpe@ellerman.id.au
Remove __init qualifier for mmu_mapin_ram_chunk() as it is called by
mmu_mark_initmem_nx() and mmu_mark_rodata_ro() which are not __init
functions.
At the same time, mark it static as it is only used in this file.
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: a2227a2777 ("powerpc/32: Don't populate page tables for block mapped pages except on the 8xx")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/56648921986a6b3e7315b1fbbf4684f21bd2dea8.1576310997.git.christophe.leroy@c-s.fr
Some powerpc platforms (e.g. 85xx) limit DMA-able memory way below 4G.
If a system has more physical memory than this limit, the swiotlb
buffer is not addressable because it is allocated from memblock using
top-down mode.
Force memblock to bottom-up mode before calling swiotlb_init() to
ensure that the swiotlb buffer is DMA-able.
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191204123524.22919-1-rppt@kernel.org
Merge updates from Andrew Morton:
"Incoming:
- a small number of updates to scripts/, ocfs2 and fs/buffer.c
- most of MM
I still have quite a lot of material (mostly not MM) staged after
linux-next due to -next dependencies. I'll send those across next week
as the preprequisites get merged up"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (135 commits)
mm/page_io.c: annotate refault stalls from swap_readpage
mm/Kconfig: fix trivial help text punctuation
mm/Kconfig: fix indentation
mm/memory_hotplug.c: remove __online_page_set_limits()
mm: fix typos in comments when calling __SetPageUptodate()
mm: fix struct member name in function comments
mm/shmem.c: cast the type of unmap_start to u64
mm: shmem: use proper gfp flags for shmem_writepage()
mm/shmem.c: make array 'values' static const, makes object smaller
userfaultfd: require CAP_SYS_PTRACE for UFFD_FEATURE_EVENT_FORK
fs/userfaultfd.c: wp: clear VM_UFFD_MISSING or VM_UFFD_WP during userfaultfd_register()
userfaultfd: wrap the common dst_vma check into an inlined function
userfaultfd: remove unnecessary WARN_ON() in __mcopy_atomic_hugetlb()
userfaultfd: use vma_pagesize for all huge page size calculation
mm/madvise.c: use PAGE_ALIGN[ED] for range checking
mm/madvise.c: replace with page_size() in madvise_inject_error()
mm/mmap.c: make vma_merge() comment more easy to understand
mm/hwpoison-inject: use DEFINE_DEBUGFS_ATTRIBUTE to define debugfs fops
autonuma: reduce cache footprint when scanning page tables
autonuma: fix watermark checking in migrate_balanced_pgdat()
...
Patch series "hugetlbfs: convert macros to static inline, fix sparse
warning".
The definition for huge_pte_offset() in <linux/hugetlb.h> causes a
sparse warning in the !CONFIG_HUGETLB_PAGE. Fix this as well as
converting all macros in this block of definitions to static inlines for
better type checking.
When making the above changes, build errors were found in powerpc due to
duplicate definitions. A separate powerpc specific patch is included as
a requisite to remove the definitions and get them from
<linux/hugetlb.h>.
This patch (of 2):
This removes the power specific stubs created by commit aad71e3928
("powerpc/mm: Fix build break with RADIX=y & HUGETLBFS=n") used when
!CONFIG_HUGETLB_PAGE. Instead, it addresses the build break by getting
the definitions from <linux/hugetlb.h>. This allows the macros in
<linux/hugetlb.h> to be replaced with static inlines.
Link: http://lkml.kernel.org/r/20191112194558.139389-2-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ben Dooks <ben.dooks@codethink.co.uk>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Highlights:
- Infrastructure for secure boot on some bare metal Power9 machines. The
firmware support is still in development, so the code here won't actually
activate secure boot on any existing systems.
- A change to xmon (our crash handler / pseudo-debugger) to restrict it to
read-only mode when the kernel is lockdown'ed, otherwise it's trivial to drop
into xmon and modify kernel data, such as the lockdown state.
- Support for KASLR on 32-bit BookE machines (Freescale / NXP).
- Fixes for our flush_icache_range() and __kernel_sync_dicache() (VDSO) to work
with memory ranges >4GB.
- Some reworks of the pseries CMM (Cooperative Memory Management) driver to
make it behave more like other balloon drivers and enable some cleanups of
generic mm code.
- A series of fixes to our hardware breakpoint support to properly handle
unaligned watchpoint addresses.
Plus a bunch of other smaller improvements, fixes and cleanups.
Thanks to:
Alastair D'Silva, Andrew Donnellan, Aneesh Kumar K.V, Anthony Steinhauser,
Cédric Le Goater, Chris Packham, Chris Smart, Christophe Leroy, Christopher M.
Riedl, Christoph Hellwig, Claudio Carvalho, Daniel Axtens, David Hildenbrand,
Deb McLemore, Diana Craciun, Eric Richter, Geert Uytterhoeven, Greg
Kroah-Hartman, Greg Kurz, Gustavo L. F. Walbon, Hari Bathini, Harish, Jason
Yan, Krzysztof Kozlowski, Leonardo Bras, Mathieu Malaterre, Mauro S. M.
Rodrigues, Michal Suchanek, Mimi Zohar, Nathan Chancellor, Nathan Lynch, Nayna
Jain, Nick Desaulniers, Oliver O'Halloran, Qian Cai, Rasmus Villemoes, Ravi
Bangoria, Sam Bobroff, Santosh Sivaraj, Scott Wood, Thomas Huth, Tyrel
Datwyler, Vaibhav Jain, Valentin Longchamp, YueHaibing.
-----BEGIN PGP SIGNATURE-----
iQJHBAABCAAxFiEEJFGtCPCthwEv2Y/bUevqPMjhpYAFAl3hBycTHG1wZUBlbGxl
cm1hbi5pZC5hdQAKCRBR6+o8yOGlgApBEACk91MEQDYJ9MF9I6uN+85qb5p4pMsp
rGzqnpt+XFidbDAc3eP63pYfIDSo3jtkQ2YL7shAnDOTvkO0md+Vqkl9Aq/G6FIf
lDBlwbgkXMSxS/O2Lpvfn4NZAoK6dKmiV55LSgfliM62X3e2Saeg6TR55wBTgJ6/
SlYPDwZfcVHOAiFS3UmfB+hkiIZk+AI5Zr5VAZvT2ZmeH36yAWkq4JgJI1uAk6m1
/7iCnlfUjx/nl/BhnA3kjjmAgGCJ5s/WuVgwFMz47XpMBWGBhLWpMh/NqDTFb8ca
kpiVQoVPQe2xyO3pL/kOwBy6sii26ftfHDhLKMy1hJdEhVQzS5LerPIMeh1qsU8Q
hV/Cj+jfsrS/vBDOehj3jwx93t+861PmTOqgLnpYQ6Ltrt+2B/74+fufGMHE1kI3
Ffo7xvNw4sw6bSziDxDFqUx2P1dFN5D5EJsJsYM98ekkVAAkzNqCDRvfD2QI8Pif
VXWPYXqtNJTrVPJA0D7Yfo9FDNwhANd0f1zi7r/U5mVXBFUyKOlGqTQSkXgMrVeK
3I7wHPOVGgdA5UUkfcd3pcuqsY081U9E//o5PUfj8ybO5JCwly8NoatbG+xHmKia
a72uJT8MjCo9mGCHKDrwi9l/kqms6ZSv8RP+yMhGuB52YoiGc6PpVyab5jXIUd1N
yTtBlC0YGW1JYw==
=JHzg
-----END PGP SIGNATURE-----
Merge tag 'powerpc-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Highlights:
- Infrastructure for secure boot on some bare metal Power9 machines.
The firmware support is still in development, so the code here
won't actually activate secure boot on any existing systems.
- A change to xmon (our crash handler / pseudo-debugger) to restrict
it to read-only mode when the kernel is lockdown'ed, otherwise it's
trivial to drop into xmon and modify kernel data, such as the
lockdown state.
- Support for KASLR on 32-bit BookE machines (Freescale / NXP).
- Fixes for our flush_icache_range() and __kernel_sync_dicache()
(VDSO) to work with memory ranges >4GB.
- Some reworks of the pseries CMM (Cooperative Memory Management)
driver to make it behave more like other balloon drivers and enable
some cleanups of generic mm code.
- A series of fixes to our hardware breakpoint support to properly
handle unaligned watchpoint addresses.
Plus a bunch of other smaller improvements, fixes and cleanups.
Thanks to: Alastair D'Silva, Andrew Donnellan, Aneesh Kumar K.V,
Anthony Steinhauser, Cédric Le Goater, Chris Packham, Chris Smart,
Christophe Leroy, Christopher M. Riedl, Christoph Hellwig, Claudio
Carvalho, Daniel Axtens, David Hildenbrand, Deb McLemore, Diana
Craciun, Eric Richter, Geert Uytterhoeven, Greg Kroah-Hartman, Greg
Kurz, Gustavo L. F. Walbon, Hari Bathini, Harish, Jason Yan, Krzysztof
Kozlowski, Leonardo Bras, Mathieu Malaterre, Mauro S. M. Rodrigues,
Michal Suchanek, Mimi Zohar, Nathan Chancellor, Nathan Lynch, Nayna
Jain, Nick Desaulniers, Oliver O'Halloran, Qian Cai, Rasmus Villemoes,
Ravi Bangoria, Sam Bobroff, Santosh Sivaraj, Scott Wood, Thomas Huth,
Tyrel Datwyler, Vaibhav Jain, Valentin Longchamp, YueHaibing"
* tag 'powerpc-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (144 commits)
powerpc/fixmap: fix crash with HIGHMEM
x86/efi: remove unused variables
powerpc: Define arch_is_kernel_initmem_freed() for lockdep
powerpc/prom_init: Use -ffreestanding to avoid a reference to bcmp
powerpc: Avoid clang warnings around setjmp and longjmp
powerpc: Don't add -mabi= flags when building with Clang
powerpc: Fix Kconfig indentation
powerpc/fixmap: don't clear fixmap area in paging_init()
selftests/powerpc: spectre_v2 test must be built 64-bit
powerpc/powernv: Disable native PCIe port management
powerpc/kexec: Move kexec files into a dedicated subdir.
powerpc/32: Split kexec low level code out of misc_32.S
powerpc/sysdev: drop simple gpio
powerpc/83xx: map IMMR with a BAT.
powerpc/32s: automatically allocate BAT in setbat()
powerpc/ioremap: warn on early use of ioremap()
powerpc: Add support for GENERIC_EARLY_IOREMAP
powerpc/fixmap: Use __fix_to_virt() instead of fix_to_virt()
powerpc/8xx: use the fixmapped IMMR in cpm_reset()
powerpc/8xx: add __init to cpm1 init functions
...
These are pure cache maintainance routines, so drop the unused
struct device argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Commit d2f15e0979 ("powerpc/32: always populate page tables for
Abatron BDI.") wrongly sets page tables for any PPC32 for using BDI,
and does't update them after init (remove RX on init section, set
text and rodata read-only)
Only the 8xx requires page tables to be populated for using the BDI.
They also need to be populated in order to see the mappings in
/sys/kernel/debug/kernel_page_tables
On BOOK3S_32, pages that are not mapped by page tables are mapped
by BATs. The BDI knows BATs and they can be viewed in
/sys/kernel/debug/powerpc/block_address_translation
Only set pagetables for RAM and IMMR on the 8xx and properly update
them at the end of init.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c8610942203e0d93fcb02ad20c57edd3adb4c9d3.1566554029.git.christophe.leroy@c-s.fr
One may want to disable kaslr when boot, so provide a cmdline parameter
'nokaslr' to support this.
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Diana Craciun <diana.craciun@nxp.com>
Tested-by: Diana Craciun <diana.craciun@nxp.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The original kernel still exists in the memory, clear it now.
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Diana Craciun <diana.craciun@nxp.com>
Tested-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
After we have the basic support of relocate the kernel in some
appropriate place, we can start to randomize the offset now.
Entropy is derived from the banner and timer, which will change every
build and boot. This not so much safe so additionally the bootloader may
pass entropy via the /chosen/kaslr-seed node in device tree.
We will use the first 512M of the low memory to randomize the kernel
image. The memory will be split in 64M zones. We will use the lower 8
bit of the entropy to decide the index of the 64M zone. Then we chose a
16K aligned offset inside the 64M zone to put the kernel in.
We also check if we will overlap with some areas like the dtb area, the
initrd area or the crashkernel area. If we cannot find a proper area,
kaslr will be disabled and boot from the original kernel.
Some pieces of code are derived from arch/x86/boot/compressed/kaslr.c or
arch/arm64/kernel/kaslr.c such as rotate_xor(). Credit goes to Kees and
Ard.
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Diana Craciun <diana.craciun@nxp.com>
Tested-by: Diana Craciun <diana.craciun@nxp.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch add support to boot kernel from places other than KERNELBASE.
Since CONFIG_RELOCATABLE has already supported, what we need to do is
map or copy kernel to a proper place and relocate. Freescale Book-E
parts expect lowmem to be mapped by fixed TLB entries(TLB1). The TLB1
entries are not suitable to map the kernel directly in a randomized
region, so we chose to copy the kernel to a proper place and restart to
relocate.
The offset of the kernel was not randomized yet(a fixed 64M is set). We
will randomize it in the next patch.
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Tested-by: Diana Craciun <diana.craciun@nxp.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
[mpe: Use PTRRELOC() in early_init()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add a new helper reloc_kernel_entry() to jump back to the start of the
new kernel. After we put the new kernel in a randomized place we can use
this new helper to enter the kernel and begin to relocate again.
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Diana Craciun <diana.craciun@nxp.com>
Tested-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add a new helper create_kaslr_tlb_entry() to create a tlb entry by the
virtual and physical address. This is a preparation to support boot kernel
at a randomized address.
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Diana Craciun <diana.craciun@nxp.com>
Tested-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Now the kernel base is a fixed value - KERNELBASE. To support KASLR, we
need a variable to store the kernel base.
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Diana Craciun <diana.craciun@nxp.com>
Tested-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Christophe Leroy
Nicholas Piggin
Aneesh Kumar K.V
Jordan Niethe
Gustavo A. R. Silva
Christophe Leroy
Logan Gunthorpe
Anshuman Khandual
Linus Torvalds
Peter Xu
Laurentiu Tudor
Michael Ellerman
Srikar Dronamraju
Alexey Kardashevskiy
Greg Kroah-Hartman
Dan Williams
Alexey Dobriyan
John Hubbard
Russell Currey
David Hildenbrand
Mike Rapoport
Mike Kravetz
Christoph Hellwig
Jason Yan