Since ISA v3.0, SLB no longer uses the slb_cache, and stab_rr is no
longer correlated with SLB allocation. Move those to pre-3.0.
While here, improve some alignments and reduce whitespace.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201128070728.825934-9-npiggin@gmail.com
"Host" caused machine check is printed when the kernel sees a MCE
hit in this kernel or userspace, and "Guest" if it hit one of its
guests. This is confusing when a guest kernel handles a hypervisor-
delivered MCE, it also prints "Host".
Just remove "Host". "Guest" is adequate to make the distinction.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201128070728.825934-8-npiggin@gmail.com
Don't treat ERAT MCEs as SLB, don't save the SLB and use a specific
ERAT flush to recover it.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201128070728.825934-7-npiggin@gmail.com
Harmless HMI errors can be triggered by guests in some cases, and don't
contain much useful information anyway. Ratelimit these to avoid
flooding the console/logs.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Use dedicated ratelimit state, not printk_ratelimit()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201128070728.825934-6-npiggin@gmail.com
A number of machine check exceptions are triggerable by the guest.
Ratelimit these to avoid a guest flooding the host console and logs.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Use dedicated ratelimit state, not printk_ratelimit()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201128070728.825934-5-npiggin@gmail.com
Guests that can deal with machine checks would actually prefer the
hypervisor not to try recover for them. For example if SLB multi-hits
are recovered by the hypervisor by clearing the SLB then the guest
will not be able to log the contents and debug its programming error.
If guests don't register for FWNMI, they may not be so capable and so
the hypervisor will continue to recover for those.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201128070728.825934-4-npiggin@gmail.com
KVM has strategies to perform machine check recovery. If a MCE hits
in a guest, have the low level handler just decode and save the MCE
but not try to recover anything, so KVM can deal with it.
The host does not own SLBs and does not need to report the SLB state
in case of a multi-hit for example, or know about the virtual memory
map of the guest.
UE and memory poisoning of guest pages in the host is one thing that
is possibly not completely robust at the moment, but this too needs
to go via KVM (possibly via the guest and back out to host via hcall)
rather than being handled at a low level in the host handler.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201128070728.825934-3-npiggin@gmail.com
The driver core ignores the return value of struct device_driver::remove
because there is only little that can be done. For the shutdown callback
it's ps3_system_bus_shutdown() which ignores the return value.
To simplify the quest to make struct device_driver::remove return void,
let struct ps3_system_bus_driver::remove return void, too. All users
already unconditionally return 0, this commit makes it obvious that
returning an error code is a bad idea and ensures future users behave
accordingly.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201126165950.2554997-2-u.kleine-koenig@pengutronix.de
Introduce a static branch that would be set during boot if the OS
happens to be a KVM guest. Subsequent checks to see if we are on KVM
will rely on this static branch. This static branch would be used in
vcpu_is_preempted() in a subsequent patch.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Waiman Long <longman@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201202050456.164005-4-srikar@linux.vnet.ibm.com
We want to reuse the is_kvm_guest() name in a subsequent patch but
with a new body. Hence rename is_kvm_guest() to check_kvm_guest(). No
additional changes.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Waiman Long <longman@redhat.com>
Signed-off-by: kernel test robot <lkp@intel.com> # int -> bool fix
[mpe: Fold in fix from lkp to use true/false not 0/1]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201202050456.164005-3-srikar@linux.vnet.ibm.com
Only code/declaration movement, in anticipation of doing a KVM-aware
vcpu_is_preempted(). No additional changes.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Waiman Long <longman@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201202050456.164005-2-srikar@linux.vnet.ibm.com
The power_pmu_event_init() callback access per-cpu variable
(cpu_hw_events) to check for event constraints and Branch Stack
(BHRB). Current usage is to disable preemption when accessing the
per-cpu variable, but this does not prevent timer callback from
interrupting event_init. Fix this by using 'local_irq_save/restore'
to make sure the code path is invoked with disabled interrupts.
This change is tested in mambo simulator to ensure that, if a timer
interrupt comes in during the per-cpu access in event_init, it will be
soft masked and replayed later. For testing purpose, introduced a
udelay() in power_pmu_event_init() to make sure a timer interrupt arrives
while in per-cpu variable access code between local_irq_save/resore.
As expected the timer interrupt was replayed later during local_irq_restore
called from power_pmu_event_init. This was confirmed by adding
breakpoint in mambo and checking the backtrace when timer_interrupt
was hit.
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1606814880-1720-1-git-send-email-atrajeev@linux.vnet.ibm.com
In a bunch of our security flushes, we use a comma rather than
a semicolon to 'terminate' an assignment. Nothing breaks, but
checkpatch picks it up if you copy it into another flush.
Switch to semicolons for ending statements.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201201144344.1228421-1-dja@axtens.net
This enables GENERIC_BUG_RELATIVE_POINTERS on Power so that 32-bit
offsets are stored in the bug entries rather than 64-bit pointers.
While this doesn't save space for 32-bit machines, use it anyway so
there is only one code path.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201201005203.15210-1-jniethe5@gmail.com
With CONFIG_PPC_8xx and CONFIG_XMON set, kernel build fails with
arch/powerpc/xmon/xmon.c:1379:12: error: 'find_free_data_bpt' defined
but not used [-Werror=unused-function]
Fix it by enclosing find_free_data_bpt() inside #ifndef CONFIG_PPC_8xx.
Fixes: 30df74d67d ("powerpc/watchpoint/xmon: Support 2nd DAWR")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201130034406.288047-1-ravi.bangoria@linux.ibm.com
Commit 63ce271b5e ("powerpc/prom: convert PROM_BUG() to standard
trap") added an EMIT_BUG_ENTRY for the trap after the branch to
start_kernel(). The EMIT_BUG_ENTRY was for the address "0b", however the
trap was not labeled with "0". Hence the address used for bug is in
relative_toc() where the previous "0" label is. Label the trap as "0" so
the correct address is used.
Fixes: 63ce271b5e ("powerpc/prom: convert PROM_BUG() to standard trap")
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201130004404.30953-1-jniethe5@gmail.com
__kernel_sync_dicache_p5() is an alternative to
__kernel_sync_dicache() when cpu has CPU_FTR_COHERENT_ICACHE
Remove this alternative function and merge
__kernel_sync_dicache_p5() into __kernel_sync_dicache() using
standard CPU feature fixup.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4c7dcc6544882761b2b0249d7a8ec2c3a8088cb5.1601197618.git.christophe.leroy@csgroup.eu
This is copied from arm64.
Instead of using runtime generated signal trampoline offsets,
get offsets at buildtime.
If the said trampoline doesn't exist, build will fail. So no
need to check whether the trampoline exists or not in the VDSO.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f8bfd6812c3e3678b1cdb4d55a52f9eb022b40d3.1601197618.git.christophe.leroy@csgroup.eu
All other architectures but s390 use a void pointer named 'vdso'
to reference the VDSO mapping.
In a following patch, the VDSO data page will be put in front of
text, vdso_base will then not anymore point to VDSO text.
To avoid confusion between vdso_base and VDSO text, rename vdso_base
into vdso and make it a void __user *.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8e6cefe474aa4ceba028abb729485cd46c140990.1601197618.git.christophe.leroy@csgroup.eu
Copied from commit 2fea7f6c98 ("arm64: vdso: move to
_install_special_mapping and remove arch_vma_name").
Use the new _install_special_mapping() API added by
commit a62c34bd2a ("x86, mm: Improve _install_special_mapping
and fix x86 vdso naming") which obsolete install_special_mapping().
And remove arch_vma_name() as the name is handled by the new API.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: kernel test robot <lkp@intel.com>
[mpe: Squash fix to use PTR_ERR_OR_ZERO() from lkp]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e7e5dfe0f93234e31051f2a610b4b07f50b0082f.1601197618.git.christophe.leroy@csgroup.eu
Today vdso_data structure has:
- syscall_map_32[] and syscall_map_64[] on PPC64
- syscall_map_32[] on PPC32
On PPC32, syscall_map_32[] is populated using sys_call_table[].
On PPC64, syscall_map_64[] is populated using sys_call_table[]
and syscal_map_32[] is populated using compat_sys_call_table[].
To simplify vdso_setup_syscall_map(),
- On PPC32 rename syscall_map_32[] into syscall_map[],
- On PPC64 rename syscall_map_64[] into syscall_map[],
- On PPC64 rename syscall_map_32[] into compat_syscall_map[].
That way, syscall_map[] gets populated using sys_call_table[] and
compat_syscall_map[] gets population using compat_sys_call_table[].
Also define an empty compat_syscall_map[] on PPC32 to avoid ifdefs.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/472734be0d9991eee320a06824219a5b2663736b.1601197618.git.christophe.leroy@csgroup.eu
Instead of including extern references locally in
vdso_setup_syscall_map(), add the missing headers.
sys_ni_syscall() being a function, cast its address to
an unsigned long instead of declaring it as a fake
unsigned long object.
At the same time, remove a comment which paraphrases the
function name.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b4afedce748ed2858299ceab5ae29b52109263ef.1601197618.git.christophe.leroy@csgroup.eu