License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 17:07:57 +03:00
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// SPDX-License-Identifier: GPL-2.0
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2008-05-20 03:52:27 +04:00
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/*
|
2005-04-17 02:20:36 +04:00
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|
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* arch/sparc64/mm/fault.c: Page fault handlers for the 64-bit Sparc.
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*
|
2008-07-18 09:11:32 +04:00
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* Copyright (C) 1996, 2008 David S. Miller (davem@davemloft.net)
|
2005-04-17 02:20:36 +04:00
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* Copyright (C) 1997, 1999 Jakub Jelinek (jj@ultra.linux.cz)
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*/
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#include <asm/head.h>
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#include <linux/string.h>
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#include <linux/types.h>
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#include <linux/sched.h>
|
2017-02-08 20:51:35 +03:00
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#include <linux/sched/debug.h>
|
2005-04-17 02:20:36 +04:00
|
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#include <linux/ptrace.h>
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|
#include <linux/mman.h>
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#include <linux/signal.h>
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#include <linux/mm.h>
|
2016-09-20 00:36:29 +03:00
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|
#include <linux/extable.h>
|
2005-04-17 02:20:36 +04:00
|
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|
#include <linux/init.h>
|
2010-01-20 14:04:14 +03:00
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|
#include <linux/perf_event.h>
|
2005-04-17 02:20:36 +04:00
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|
#include <linux/interrupt.h>
|
2005-09-07 02:19:30 +04:00
|
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|
#include <linux/kprobes.h>
|
2007-05-08 11:27:03 +04:00
|
|
|
#include <linux/kdebug.h>
|
2009-02-03 09:08:15 +03:00
|
|
|
#include <linux/percpu.h>
|
2013-09-14 16:02:11 +04:00
|
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|
#include <linux/context_tracking.h>
|
2015-05-11 18:52:11 +03:00
|
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|
#include <linux/uaccess.h>
|
2005-04-17 02:20:36 +04:00
|
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|
#include <asm/page.h>
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|
#include <asm/openprom.h>
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|
#include <asm/oplib.h>
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|
#include <asm/asi.h>
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#include <asm/lsu.h>
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#include <asm/sections.h>
|
[SPARC64]: Fix and re-enable dynamic TSB sizing.
This is good for up to %50 performance improvement of some test cases.
The problem has been the race conditions, and hopefully I've plugged
them all up here.
1) There was a serious race in switch_mm() wrt. lazy TLB
switching to and from kernel threads.
We could erroneously skip a tsb_context_switch() and thus
use a stale TSB across a TSB grow event.
There is a big comment now in that function describing
exactly how it can happen.
2) All code paths that do something with the TSB need to be
guarded with the mm->context.lock spinlock. This makes
page table flushing paths properly synchronize with both
TSB growing and TLB context changes.
3) TSB growing events are moved to the end of successful fault
processing. Previously it was in update_mmu_cache() but
that is deadlock prone. At the end of do_sparc64_fault()
we hold no spinlocks that could deadlock the TSB grow
sequence. We also have dropped the address space semaphore.
While we're here, add prefetching to the copy_tsb() routine
and put it in assembler into the tsb.S file. This piece of
code is quite time critical.
There are some small negative side effects to this code which
can be improved upon. In particular we grab the mm->context.lock
even for the tsb insert done by update_mmu_cache() now and that's
a bit excessive. We can get rid of that locking, and the same
lock taking in flush_tsb_user(), by disabling PSTATE_IE around
the whole operation including the capturing of the tsb pointer
and tsb_nentries value. That would work because anyone growing
the TSB won't free up the old TSB until all cpus respond to the
TSB change cross call.
I'm not quite so confident in that optimization to put it in
right now, but eventually we might be able to and the description
is here for reference.
This code seems very solid now. It passes several parallel GCC
bootstrap builds, and our favorite "nut cruncher" stress test which is
a full "make -j8192" build of a "make allmodconfig" kernel. That puts
about 256 processes on each cpu's run queue, makes lots of process cpu
migrations occur, causes lots of page table and TLB flushing activity,
incurs many context version number changes, and it swaps the machine
real far out to disk even though there is 16GB of ram on this test
system. :-)
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-16 13:02:32 +03:00
|
|
|
#include <asm/mmu_context.h>
|
2014-05-17 01:25:54 +04:00
|
|
|
#include <asm/setup.h>
|
2005-04-17 02:20:36 +04:00
|
|
|
|
2010-03-01 11:02:23 +03:00
|
|
|
int show_unhandled_signals = 1;
|
|
|
|
|
|
2005-09-07 02:19:30 +04:00
|
|
|
static void __kprobes unhandled_fault(unsigned long address,
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|
|
|
|
struct task_struct *tsk,
|
|
|
|
|
struct pt_regs *regs)
|
2005-04-17 02:20:36 +04:00
|
|
|
{
|
|
|
|
|
if ((unsigned long) address < PAGE_SIZE) {
|
|
|
|
|
printk(KERN_ALERT "Unable to handle kernel NULL "
|
|
|
|
|
"pointer dereference\n");
|
|
|
|
|
} else {
|
|
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|
printk(KERN_ALERT "Unable to handle kernel paging request "
|
|
|
|
|
"at virtual address %016lx\n", (unsigned long)address);
|
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|
|
|
}
|
|
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|
|
printk(KERN_ALERT "tsk->{mm,active_mm}->context = %016lx\n",
|
|
|
|
|
(tsk->mm ?
|
|
|
|
|
CTX_HWBITS(tsk->mm->context) :
|
|
|
|
|
CTX_HWBITS(tsk->active_mm->context)));
|
|
|
|
|
printk(KERN_ALERT "tsk->{mm,active_mm}->pgd = %016lx\n",
|
|
|
|
|
(tsk->mm ? (unsigned long) tsk->mm->pgd :
|
|
|
|
|
(unsigned long) tsk->active_mm->pgd));
|
|
|
|
|
die_if_kernel("Oops", regs);
|
|
|
|
|
}
|
|
|
|
|
|
2009-12-11 05:08:29 +03:00
|
|
|
static void __kprobes bad_kernel_pc(struct pt_regs *regs, unsigned long vaddr)
|
2005-04-17 02:20:36 +04:00
|
|
|
{
|
|
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|
printk(KERN_CRIT "OOPS: Bogus kernel PC [%016lx] in fault handler\n",
|
|
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|
|
regs->tpc);
|
2006-07-22 12:12:09 +04:00
|
|
|
printk(KERN_CRIT "OOPS: RPC [%016lx]\n", regs->u_regs[15]);
|
2008-07-18 09:11:32 +04:00
|
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|
printk("OOPS: RPC <%pS>\n", (void *) regs->u_regs[15]);
|
2006-02-14 05:07:45 +03:00
|
|
|
printk(KERN_CRIT "OOPS: Fault was to vaddr[%lx]\n", vaddr);
|
2007-07-30 11:17:12 +04:00
|
|
|
dump_stack();
|
2005-04-17 02:20:36 +04:00
|
|
|
unhandled_fault(regs->tpc, current, regs);
|
|
|
|
|
}
|
|
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|
|
|
|
|
|
|
/*
|
2020-06-09 07:33:54 +03:00
|
|
|
* We now make sure that mmap_lock is held in all paths that call
|
2005-04-17 02:20:36 +04:00
|
|
|
* this. Additionally, to prevent kswapd from ripping ptes from
|
|
|
|
|
* under us, raise interrupts around the time that we look at the
|
|
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|
|
* pte, kswapd will have to wait to get his smp ipi response from
|
2005-11-08 21:00:55 +03:00
|
|
|
* us. vmtruncate likewise. This saves us having to get pte lock.
|
2005-04-17 02:20:36 +04:00
|
|
|
*/
|
|
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|
|
static unsigned int get_user_insn(unsigned long tpc)
|
|
|
|
|
{
|
|
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|
|
pgd_t *pgdp = pgd_offset(current->mm, tpc);
|
2019-11-24 11:57:20 +03:00
|
|
|
p4d_t *p4dp;
|
2005-04-17 02:20:36 +04:00
|
|
|
pud_t *pudp;
|
|
|
|
|
pmd_t *pmdp;
|
|
|
|
|
pte_t *ptep, pte;
|
|
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|
|
unsigned long pa;
|
|
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|
|
u32 insn = 0;
|
|
|
|
|
|
2014-04-29 10:52:11 +04:00
|
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|
if (pgd_none(*pgdp) || unlikely(pgd_bad(*pgdp)))
|
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|
goto out;
|
2019-11-24 11:57:20 +03:00
|
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|
p4dp = p4d_offset(pgdp, tpc);
|
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|
if (p4d_none(*p4dp) || unlikely(p4d_bad(*p4dp)))
|
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|
goto out;
|
|
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|
pudp = pud_offset(p4dp, tpc);
|
2014-04-29 10:52:11 +04:00
|
|
|
if (pud_none(*pudp) || unlikely(pud_bad(*pudp)))
|
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|
goto out;
|
2005-04-17 02:20:36 +04:00
|
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|
/* This disables preemption for us as well. */
|
2014-04-29 10:52:11 +04:00
|
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|
local_irq_disable();
|
2005-04-17 02:20:36 +04:00
|
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|
|
2014-04-29 10:52:11 +04:00
|
|
|
pmdp = pmd_offset(pudp, tpc);
|
|
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|
|
if (pmd_none(*pmdp) || unlikely(pmd_bad(*pmdp)))
|
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|
goto out_irq_enable;
|
|
|
|
|
|
2016-07-29 10:54:21 +03:00
|
|
|
#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
|
|
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|
|
if (is_hugetlb_pmd(*pmdp)) {
|
2014-04-29 10:52:11 +04:00
|
|
|
pa = pmd_pfn(*pmdp) << PAGE_SHIFT;
|
|
|
|
|
pa += tpc & ~HPAGE_MASK;
|
2005-04-17 02:20:36 +04:00
|
|
|
|
2014-04-29 10:52:11 +04:00
|
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|
/* Use phys bypass so we don't pollute dtlb/dcache. */
|
|
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|
__asm__ __volatile__("lduwa [%1] %2, %0"
|
|
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|
|
: "=r" (insn)
|
|
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: "r" (pa), "i" (ASI_PHYS_USE_EC));
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} else
|
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#endif
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|
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{
|
|
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|
|
ptep = pte_offset_map(pmdp, tpc);
|
|
|
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|
pte = *ptep;
|
|
|
|
|
if (pte_present(pte)) {
|
|
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|
|
pa = (pte_pfn(pte) << PAGE_SHIFT);
|
|
|
|
|
pa += (tpc & ~PAGE_MASK);
|
|
|
|
|
|
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/* Use phys bypass so we don't pollute dtlb/dcache. */
|
|
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|
__asm__ __volatile__("lduwa [%1] %2, %0"
|
|
|
|
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: "=r" (insn)
|
|
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|
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: "r" (pa), "i" (ASI_PHYS_USE_EC));
|
|
|
|
|
}
|
|
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|
|
pte_unmap(ptep);
|
|
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|
|
}
|
|
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|
|
out_irq_enable:
|
|
|
|
|
local_irq_enable();
|
2005-04-17 02:20:36 +04:00
|
|
|
out:
|
|
|
|
|
return insn;
|
|
|
|
|
}
|
|
|
|
|
|
2010-03-01 11:02:23 +03:00
|
|
|
static inline void
|
|
|
|
|
show_signal_msg(struct pt_regs *regs, int sig, int code,
|
|
|
|
|
unsigned long address, struct task_struct *tsk)
|
|
|
|
|
{
|
|
|
|
|
if (!unhandled_signal(tsk, sig))
|
|
|
|
|
return;
|
|
|
|
|
|
|
|
|
|
if (!printk_ratelimit())
|
|
|
|
|
return;
|
|
|
|
|
|
2017-12-20 00:52:23 +03:00
|
|
|
printk("%s%s[%d]: segfault at %lx ip %px (rpc %px) sp %px error %x",
|
2010-03-01 11:02:23 +03:00
|
|
|
task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
|
|
|
|
|
tsk->comm, task_pid_nr(tsk), address,
|
|
|
|
|
(void *)regs->tpc, (void *)regs->u_regs[UREG_I7],
|
|
|
|
|
(void *)regs->u_regs[UREG_FP], code);
|
|
|
|
|
|
|
|
|
|
print_vma_addr(KERN_CONT " in ", regs->tpc);
|
|
|
|
|
|
|
|
|
|
printk(KERN_CONT "\n");
|
|
|
|
|
}
|
|
|
|
|
|
2005-04-17 02:20:36 +04:00
|
|
|
static void do_fault_siginfo(int code, int sig, struct pt_regs *regs,
|
2014-04-29 10:52:11 +04:00
|
|
|
unsigned long fault_addr, unsigned int insn,
|
|
|
|
|
int fault_code)
|
2005-04-17 02:20:36 +04:00
|
|
|
{
|
2010-03-01 11:02:23 +03:00
|
|
|
unsigned long addr;
|
2005-04-17 02:20:36 +04:00
|
|
|
|
2014-04-29 10:52:11 +04:00
|
|
|
if (fault_code & FAULT_CODE_ITLB) {
|
2010-03-01 11:02:23 +03:00
|
|
|
addr = regs->tpc;
|
2014-04-29 10:52:11 +04:00
|
|
|
} else {
|
|
|
|
|
/* If we were able to probe the faulting instruction, use it
|
|
|
|
|
* to compute a precise fault address. Otherwise use the fault
|
|
|
|
|
* time provided address which may only have page granularity.
|
|
|
|
|
*/
|
|
|
|
|
if (insn)
|
|
|
|
|
addr = compute_effective_address(regs, insn, 0);
|
|
|
|
|
else
|
|
|
|
|
addr = fault_addr;
|
|
|
|
|
}
|
2010-03-01 11:02:23 +03:00
|
|
|
|
|
|
|
|
if (unlikely(show_unhandled_signals))
|
|
|
|
|
show_signal_msg(regs, sig, code, addr, current);
|
|
|
|
|
|
2019-05-23 19:04:24 +03:00
|
|
|
force_sig_fault(sig, code, (void __user *) addr, 0);
|
2005-04-17 02:20:36 +04:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static unsigned int get_fault_insn(struct pt_regs *regs, unsigned int insn)
|
|
|
|
|
{
|
|
|
|
|
if (!insn) {
|
|
|
|
|
if (!regs->tpc || (regs->tpc & 0x3))
|
|
|
|
|
return 0;
|
|
|
|
|
if (regs->tstate & TSTATE_PRIV) {
|
|
|
|
|
insn = *(unsigned int *) regs->tpc;
|
|
|
|
|
} else {
|
|
|
|
|
insn = get_user_insn(regs->tpc);
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
return insn;
|
|
|
|
|
}
|
|
|
|
|
|
2009-12-11 05:08:29 +03:00
|
|
|
static void __kprobes do_kernel_fault(struct pt_regs *regs, int si_code,
|
|
|
|
|
int fault_code, unsigned int insn,
|
|
|
|
|
unsigned long address)
|
2005-04-17 02:20:36 +04:00
|
|
|
{
|
|
|
|
|
unsigned char asi = ASI_P;
|
|
|
|
|
|
|
|
|
|
if ((!insn) && (regs->tstate & TSTATE_PRIV))
|
|
|
|
|
goto cannot_handle;
|
|
|
|
|
|
|
|
|
|
/* If user insn could be read (thus insn is zero), that
|
|
|
|
|
* is fine. We will just gun down the process with a signal
|
|
|
|
|
* in that case.
|
|
|
|
|
*/
|
|
|
|
|
|
|
|
|
|
if (!(fault_code & (FAULT_CODE_WRITE|FAULT_CODE_ITLB)) &&
|
|
|
|
|
(insn & 0xc0800000) == 0xc0800000) {
|
|
|
|
|
if (insn & 0x2000)
|
|
|
|
|
asi = (regs->tstate >> 24);
|
|
|
|
|
else
|
|
|
|
|
asi = (insn >> 5);
|
|
|
|
|
if ((asi & 0xf2) == 0x82) {
|
|
|
|
|
if (insn & 0x1000000) {
|
|
|
|
|
handle_ldf_stq(insn, regs);
|
|
|
|
|
} else {
|
|
|
|
|
/* This was a non-faulting load. Just clear the
|
|
|
|
|
* destination register(s) and continue with the next
|
|
|
|
|
* instruction. -jj
|
|
|
|
|
*/
|
|
|
|
|
handle_ld_nf(insn, regs);
|
|
|
|
|
}
|
|
|
|
|
return;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* Is this in ex_table? */
|
|
|
|
|
if (regs->tstate & TSTATE_PRIV) {
|
2005-09-29 07:21:11 +04:00
|
|
|
const struct exception_table_entry *entry;
|
2005-04-17 02:20:36 +04:00
|
|
|
|
2008-02-27 04:30:02 +03:00
|
|
|
entry = search_exception_tables(regs->tpc);
|
|
|
|
|
if (entry) {
|
2005-09-29 07:21:11 +04:00
|
|
|
regs->tpc = entry->fixup;
|
2005-04-17 02:20:36 +04:00
|
|
|
regs->tnpc = regs->tpc + 4;
|
|
|
|
|
return;
|
|
|
|
|
}
|
|
|
|
|
} else {
|
|
|
|
|
/* The si_code was set to make clear whether
|
|
|
|
|
* this was a SEGV_MAPERR or SEGV_ACCERR fault.
|
|
|
|
|
*/
|
2014-04-29 10:52:11 +04:00
|
|
|
do_fault_siginfo(si_code, SIGSEGV, regs, address, insn, fault_code);
|
2005-04-17 02:20:36 +04:00
|
|
|
return;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
cannot_handle:
|
|
|
|
|
unhandled_fault (address, current, regs);
|
|
|
|
|
}
|
|
|
|
|
|
2009-12-11 05:08:29 +03:00
|
|
|
static void noinline __kprobes bogus_32bit_fault_tpc(struct pt_regs *regs)
|
2009-02-04 03:28:23 +03:00
|
|
|
{
|
|
|
|
|
static int times;
|
|
|
|
|
|
|
|
|
|
if (times++ < 10)
|
|
|
|
|
printk(KERN_ERR "FAULT[%s:%d]: 32-bit process reports "
|
|
|
|
|
"64-bit TPC [%lx]\n",
|
|
|
|
|
current->comm, current->pid,
|
|
|
|
|
regs->tpc);
|
|
|
|
|
show_regs(regs);
|
|
|
|
|
}
|
|
|
|
|
|
2005-09-07 02:19:30 +04:00
|
|
|
asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
|
2005-04-17 02:20:36 +04:00
|
|
|
{
|
2013-09-14 16:02:11 +04:00
|
|
|
enum ctx_state prev_state = exception_enter();
|
2005-04-17 02:20:36 +04:00
|
|
|
struct mm_struct *mm = current->mm;
|
|
|
|
|
struct vm_area_struct *vma;
|
|
|
|
|
unsigned int insn = 0;
|
2018-08-18 01:44:47 +03:00
|
|
|
int si_code, fault_code;
|
|
|
|
|
vm_fault_t fault;
|
[SPARC64]: Fix and re-enable dynamic TSB sizing.
This is good for up to %50 performance improvement of some test cases.
The problem has been the race conditions, and hopefully I've plugged
them all up here.
1) There was a serious race in switch_mm() wrt. lazy TLB
switching to and from kernel threads.
We could erroneously skip a tsb_context_switch() and thus
use a stale TSB across a TSB grow event.
There is a big comment now in that function describing
exactly how it can happen.
2) All code paths that do something with the TSB need to be
guarded with the mm->context.lock spinlock. This makes
page table flushing paths properly synchronize with both
TSB growing and TLB context changes.
3) TSB growing events are moved to the end of successful fault
processing. Previously it was in update_mmu_cache() but
that is deadlock prone. At the end of do_sparc64_fault()
we hold no spinlocks that could deadlock the TSB grow
sequence. We also have dropped the address space semaphore.
While we're here, add prefetching to the copy_tsb() routine
and put it in assembler into the tsb.S file. This piece of
code is quite time critical.
There are some small negative side effects to this code which
can be improved upon. In particular we grab the mm->context.lock
even for the tsb insert done by update_mmu_cache() now and that's
a bit excessive. We can get rid of that locking, and the same
lock taking in flush_tsb_user(), by disabling PSTATE_IE around
the whole operation including the capturing of the tsb pointer
and tsb_nentries value. That would work because anyone growing
the TSB won't free up the old TSB until all cpus respond to the
TSB change cross call.
I'm not quite so confident in that optimization to put it in
right now, but eventually we might be able to and the description
is here for reference.
This code seems very solid now. It passes several parallel GCC
bootstrap builds, and our favorite "nut cruncher" stress test which is
a full "make -j8192" build of a "make allmodconfig" kernel. That puts
about 256 processes on each cpu's run queue, makes lots of process cpu
migrations occur, causes lots of page table and TLB flushing activity,
incurs many context version number changes, and it swaps the machine
real far out to disk even though there is 16GB of ram on this test
system. :-)
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-16 13:02:32 +03:00
|
|
|
unsigned long address, mm_rss;
|
2020-04-02 07:08:37 +03:00
|
|
|
unsigned int flags = FAULT_FLAG_DEFAULT;
|
2005-04-17 02:20:36 +04:00
|
|
|
|
|
|
|
|
fault_code = get_thread_fault_code();
|
|
|
|
|
|
2019-07-17 02:28:00 +03:00
|
|
|
if (kprobe_page_fault(regs, 0))
|
2013-09-14 16:02:11 +04:00
|
|
|
goto exit_exception;
|
2005-04-17 02:20:36 +04:00
|
|
|
|
|
|
|
|
si_code = SEGV_MAPERR;
|
|
|
|
|
address = current_thread_info()->fault_address;
|
|
|
|
|
|
|
|
|
|
if ((fault_code & FAULT_CODE_ITLB) &&
|
|
|
|
|
(fault_code & FAULT_CODE_DTLB))
|
|
|
|
|
BUG();
|
|
|
|
|
|
2009-02-03 09:08:15 +03:00
|
|
|
if (test_thread_flag(TIF_32BIT)) {
|
2009-02-04 03:28:23 +03:00
|
|
|
if (!(regs->tstate & TSTATE_PRIV)) {
|
|
|
|
|
if (unlikely((regs->tpc >> 32) != 0)) {
|
|
|
|
|
bogus_32bit_fault_tpc(regs);
|
|
|
|
|
goto intr_or_no_mm;
|
|
|
|
|
}
|
|
|
|
|
}
|
2014-05-07 08:27:37 +04:00
|
|
|
if (unlikely((address >> 32) != 0))
|
2009-02-04 03:28:23 +03:00
|
|
|
goto intr_or_no_mm;
|
2009-02-03 09:08:15 +03:00
|
|
|
}
|
|
|
|
|
|
2005-04-17 02:20:36 +04:00
|
|
|
if (regs->tstate & TSTATE_PRIV) {
|
2009-02-04 03:28:23 +03:00
|
|
|
unsigned long tpc = regs->tpc;
|
2005-04-17 02:20:36 +04:00
|
|
|
|
|
|
|
|
/* Sanity check the PC. */
|
2008-02-29 07:38:15 +03:00
|
|
|
if ((tpc >= KERNBASE && tpc < (unsigned long) __init_end) ||
|
2005-04-17 02:20:36 +04:00
|
|
|
(tpc >= MODULES_VADDR && tpc < MODULES_END)) {
|
|
|
|
|
/* Valid, no problems... */
|
|
|
|
|
} else {
|
2006-02-14 05:07:45 +03:00
|
|
|
bad_kernel_pc(regs, address);
|
2013-09-14 16:02:11 +04:00
|
|
|
goto exit_exception;
|
2005-04-17 02:20:36 +04:00
|
|
|
}
|
2013-09-13 02:13:39 +04:00
|
|
|
} else
|
|
|
|
|
flags |= FAULT_FLAG_USER;
|
2005-04-17 02:20:36 +04:00
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* If we're in an interrupt or have no user
|
|
|
|
|
* context, we must not take the fault..
|
|
|
|
|
*/
|
2015-05-11 18:52:11 +03:00
|
|
|
if (faulthandler_disabled() || !mm)
|
2005-04-17 02:20:36 +04:00
|
|
|
goto intr_or_no_mm;
|
|
|
|
|
|
2011-06-27 16:41:57 +04:00
|
|
|
perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
|
2010-01-20 14:04:14 +03:00
|
|
|
|
2020-06-09 07:33:25 +03:00
|
|
|
if (!mmap_read_trylock(mm)) {
|
2005-04-17 02:20:36 +04:00
|
|
|
if ((regs->tstate & TSTATE_PRIV) &&
|
|
|
|
|
!search_exception_tables(regs->tpc)) {
|
|
|
|
|
insn = get_fault_insn(regs, insn);
|
|
|
|
|
goto handle_kernel_fault;
|
|
|
|
|
}
|
2012-03-26 10:40:49 +04:00
|
|
|
|
|
|
|
|
retry:
|
2020-06-09 07:33:25 +03:00
|
|
|
mmap_read_lock(mm);
|
2005-04-17 02:20:36 +04:00
|
|
|
}
|
|
|
|
|
|
2014-09-16 17:26:47 +04:00
|
|
|
if (fault_code & FAULT_CODE_BAD_RA)
|
|
|
|
|
goto do_sigbus;
|
|
|
|
|
|
2005-04-17 02:20:36 +04:00
|
|
|
vma = find_vma(mm, address);
|
|
|
|
|
if (!vma)
|
|
|
|
|
goto bad_area;
|
|
|
|
|
|
|
|
|
|
/* Pure DTLB misses do not tell us whether the fault causing
|
|
|
|
|
* load/store/atomic was a write or not, it only says that there
|
|
|
|
|
* was no match. So in such a case we (carefully) read the
|
|
|
|
|
* instruction to try and figure this out. It's an optimization
|
|
|
|
|
* so it's ok if we can't do this.
|
|
|
|
|
*
|
|
|
|
|
* Special hack, window spill/fill knows the exact fault type.
|
|
|
|
|
*/
|
|
|
|
|
if (((fault_code &
|
|
|
|
|
(FAULT_CODE_DTLB | FAULT_CODE_WRITE | FAULT_CODE_WINFIXUP)) == FAULT_CODE_DTLB) &&
|
|
|
|
|
(vma->vm_flags & VM_WRITE) != 0) {
|
|
|
|
|
insn = get_fault_insn(regs, 0);
|
|
|
|
|
if (!insn)
|
|
|
|
|
goto continue_fault;
|
2006-03-29 01:32:24 +04:00
|
|
|
/* All loads, stores and atomics have bits 30 and 31 both set
|
|
|
|
|
* in the instruction. Bit 21 is set in all stores, but we
|
|
|
|
|
* have to avoid prefetches which also have bit 21 set.
|
|
|
|
|
*/
|
2005-04-17 02:20:36 +04:00
|
|
|
if ((insn & 0xc0200000) == 0xc0200000 &&
|
2006-03-29 01:32:24 +04:00
|
|
|
(insn & 0x01780000) != 0x01680000) {
|
2005-04-17 02:20:36 +04:00
|
|
|
/* Don't bother updating thread struct value,
|
|
|
|
|
* because update_mmu_cache only cares which tlb
|
|
|
|
|
* the access came from.
|
|
|
|
|
*/
|
|
|
|
|
fault_code |= FAULT_CODE_WRITE;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
continue_fault:
|
|
|
|
|
|
|
|
|
|
if (vma->vm_start <= address)
|
|
|
|
|
goto good_area;
|
|
|
|
|
if (!(vma->vm_flags & VM_GROWSDOWN))
|
|
|
|
|
goto bad_area;
|
|
|
|
|
if (!(fault_code & FAULT_CODE_WRITE)) {
|
|
|
|
|
/* Non-faulting loads shouldn't expand stack. */
|
|
|
|
|
insn = get_fault_insn(regs, insn);
|
|
|
|
|
if ((insn & 0xc0800000) == 0xc0800000) {
|
|
|
|
|
unsigned char asi;
|
|
|
|
|
|
|
|
|
|
if (insn & 0x2000)
|
|
|
|
|
asi = (regs->tstate >> 24);
|
|
|
|
|
else
|
|
|
|
|
asi = (insn >> 5);
|
|
|
|
|
if ((asi & 0xf2) == 0x82)
|
|
|
|
|
goto bad_area;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
if (expand_stack(vma, address))
|
|
|
|
|
goto bad_area;
|
|
|
|
|
/*
|
|
|
|
|
* Ok, we have a good vm_area for this memory access, so
|
|
|
|
|
* we can handle it..
|
|
|
|
|
*/
|
|
|
|
|
good_area:
|
|
|
|
|
si_code = SEGV_ACCERR;
|
|
|
|
|
|
|
|
|
|
/* If we took a ITLB miss on a non-executable page, catch
|
|
|
|
|
* that here.
|
|
|
|
|
*/
|
|
|
|
|
if ((fault_code & FAULT_CODE_ITLB) && !(vma->vm_flags & VM_EXEC)) {
|
2015-06-15 23:15:44 +03:00
|
|
|
WARN(address != regs->tpc,
|
|
|
|
|
"address (%lx) != regs->tpc (%lx)\n", address, regs->tpc);
|
|
|
|
|
WARN_ON(regs->tstate & TSTATE_PRIV);
|
2005-04-17 02:20:36 +04:00
|
|
|
goto bad_area;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (fault_code & FAULT_CODE_WRITE) {
|
|
|
|
|
if (!(vma->vm_flags & VM_WRITE))
|
|
|
|
|
goto bad_area;
|
|
|
|
|
|
|
|
|
|
/* Spitfire has an icache which does not snoop
|
|
|
|
|
* processor stores. Later processors do...
|
|
|
|
|
*/
|
|
|
|
|
if (tlb_type == spitfire &&
|
|
|
|
|
(vma->vm_flags & VM_EXEC) != 0 &&
|
|
|
|
|
vma->vm_file != NULL)
|
|
|
|
|
set_thread_fault_code(fault_code |
|
|
|
|
|
FAULT_CODE_BLKCOMMIT);
|
2013-09-13 02:13:39 +04:00
|
|
|
|
|
|
|
|
flags |= FAULT_FLAG_WRITE;
|
2005-04-17 02:20:36 +04:00
|
|
|
} else {
|
|
|
|
|
/* Allow reads even for write-only mappings */
|
|
|
|
|
if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
|
|
|
|
|
goto bad_area;
|
|
|
|
|
}
|
|
|
|
|
|
2020-08-12 04:38:46 +03:00
|
|
|
fault = handle_mm_fault(vma, address, flags, regs);
|
2012-03-26 10:40:49 +04:00
|
|
|
|
2020-04-02 07:08:06 +03:00
|
|
|
if (fault_signal_pending(fault, regs))
|
2013-09-14 16:02:11 +04:00
|
|
|
goto exit_exception;
|
2012-03-26 10:40:49 +04:00
|
|
|
|
2007-07-19 12:47:05 +04:00
|
|
|
if (unlikely(fault & VM_FAULT_ERROR)) {
|
|
|
|
|
if (fault & VM_FAULT_OOM)
|
|
|
|
|
goto out_of_memory;
|
vm: add VM_FAULT_SIGSEGV handling support
The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.
That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works. However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.
In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV. And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.
However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space. And user space really
expected SIGSEGV, not SIGBUS.
To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it. They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.
This is the mindless minimal patch to do this. A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.
Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.
Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-29 21:51:32 +03:00
|
|
|
else if (fault & VM_FAULT_SIGSEGV)
|
|
|
|
|
goto bad_area;
|
2007-07-19 12:47:05 +04:00
|
|
|
else if (fault & VM_FAULT_SIGBUS)
|
|
|
|
|
goto do_sigbus;
|
2005-04-17 02:20:36 +04:00
|
|
|
BUG();
|
|
|
|
|
}
|
2012-03-26 10:40:49 +04:00
|
|
|
|
|
|
|
|
if (flags & FAULT_FLAG_ALLOW_RETRY) {
|
|
|
|
|
if (fault & VM_FAULT_RETRY) {
|
2012-10-09 03:32:19 +04:00
|
|
|
flags |= FAULT_FLAG_TRIED;
|
2012-03-26 10:40:49 +04:00
|
|
|
|
2020-06-09 07:33:51 +03:00
|
|
|
/* No need to mmap_read_unlock(mm) as we would
|
2012-03-26 10:40:49 +04:00
|
|
|
* have already released it in __lock_page_or_retry
|
|
|
|
|
* in mm/filemap.c.
|
|
|
|
|
*/
|
|
|
|
|
|
|
|
|
|
goto retry;
|
|
|
|
|
}
|
2010-01-20 14:04:14 +03:00
|
|
|
}
|
2020-06-09 07:33:25 +03:00
|
|
|
mmap_read_unlock(mm);
|
[SPARC64]: Fix and re-enable dynamic TSB sizing.
This is good for up to %50 performance improvement of some test cases.
The problem has been the race conditions, and hopefully I've plugged
them all up here.
1) There was a serious race in switch_mm() wrt. lazy TLB
switching to and from kernel threads.
We could erroneously skip a tsb_context_switch() and thus
use a stale TSB across a TSB grow event.
There is a big comment now in that function describing
exactly how it can happen.
2) All code paths that do something with the TSB need to be
guarded with the mm->context.lock spinlock. This makes
page table flushing paths properly synchronize with both
TSB growing and TLB context changes.
3) TSB growing events are moved to the end of successful fault
processing. Previously it was in update_mmu_cache() but
that is deadlock prone. At the end of do_sparc64_fault()
we hold no spinlocks that could deadlock the TSB grow
sequence. We also have dropped the address space semaphore.
While we're here, add prefetching to the copy_tsb() routine
and put it in assembler into the tsb.S file. This piece of
code is quite time critical.
There are some small negative side effects to this code which
can be improved upon. In particular we grab the mm->context.lock
even for the tsb insert done by update_mmu_cache() now and that's
a bit excessive. We can get rid of that locking, and the same
lock taking in flush_tsb_user(), by disabling PSTATE_IE around
the whole operation including the capturing of the tsb pointer
and tsb_nentries value. That would work because anyone growing
the TSB won't free up the old TSB until all cpus respond to the
TSB change cross call.
I'm not quite so confident in that optimization to put it in
right now, but eventually we might be able to and the description
is here for reference.
This code seems very solid now. It passes several parallel GCC
bootstrap builds, and our favorite "nut cruncher" stress test which is
a full "make -j8192" build of a "make allmodconfig" kernel. That puts
about 256 processes on each cpu's run queue, makes lots of process cpu
migrations occur, causes lots of page table and TLB flushing activity,
incurs many context version number changes, and it swaps the machine
real far out to disk even though there is 16GB of ram on this test
system. :-)
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-16 13:02:32 +03:00
|
|
|
|
|
|
|
|
mm_rss = get_mm_rss(mm);
|
2016-07-15 23:08:42 +03:00
|
|
|
#if defined(CONFIG_TRANSPARENT_HUGEPAGE)
|
|
|
|
|
mm_rss -= (mm->context.thp_pte_count * (HPAGE_SIZE / PAGE_SIZE));
|
2006-03-22 11:49:59 +03:00
|
|
|
#endif
|
2006-03-27 13:07:55 +04:00
|
|
|
if (unlikely(mm_rss >
|
2006-03-22 11:49:59 +03:00
|
|
|
mm->context.tsb_block[MM_TSB_BASE].tsb_rss_limit))
|
|
|
|
|
tsb_grow(mm, MM_TSB_BASE, mm_rss);
|
2012-10-09 03:34:29 +04:00
|
|
|
#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
|
2016-07-15 23:08:42 +03:00
|
|
|
mm_rss = mm->context.hugetlb_pte_count + mm->context.thp_pte_count;
|
2016-08-31 23:48:19 +03:00
|
|
|
mm_rss *= REAL_HPAGE_PER_HPAGE;
|
2006-03-27 13:07:55 +04:00
|
|
|
if (unlikely(mm_rss >
|
2013-02-20 10:34:10 +04:00
|
|
|
mm->context.tsb_block[MM_TSB_HUGE].tsb_rss_limit)) {
|
|
|
|
|
if (mm->context.tsb_block[MM_TSB_HUGE].tsb)
|
|
|
|
|
tsb_grow(mm, MM_TSB_HUGE, mm_rss);
|
|
|
|
|
else
|
|
|
|
|
hugetlb_setup(regs);
|
|
|
|
|
|
|
|
|
|
}
|
2006-03-22 11:49:59 +03:00
|
|
|
#endif
|
2013-09-14 16:02:11 +04:00
|
|
|
exit_exception:
|
|
|
|
|
exception_exit(prev_state);
|
2005-09-29 08:06:47 +04:00
|
|
|
return;
|
2005-04-17 02:20:36 +04:00
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Something tried to access memory that isn't in our memory map..
|
|
|
|
|
* Fix it, but check if it's kernel or user first..
|
|
|
|
|
*/
|
|
|
|
|
bad_area:
|
|
|
|
|
insn = get_fault_insn(regs, insn);
|
2020-06-09 07:33:25 +03:00
|
|
|
mmap_read_unlock(mm);
|
2005-04-17 02:20:36 +04:00
|
|
|
|
|
|
|
|
handle_kernel_fault:
|
|
|
|
|
do_kernel_fault(regs, si_code, fault_code, insn, address);
|
2013-09-14 16:02:11 +04:00
|
|
|
goto exit_exception;
|
2005-04-17 02:20:36 +04:00
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* We ran out of memory, or some other thing happened to us that made
|
|
|
|
|
* us unable to handle the page fault gracefully.
|
|
|
|
|
*/
|
|
|
|
|
out_of_memory:
|
|
|
|
|
insn = get_fault_insn(regs, insn);
|
2020-06-09 07:33:25 +03:00
|
|
|
mmap_read_unlock(mm);
|
2009-08-03 06:17:15 +04:00
|
|
|
if (!(regs->tstate & TSTATE_PRIV)) {
|
|
|
|
|
pagefault_out_of_memory();
|
2013-09-14 16:02:11 +04:00
|
|
|
goto exit_exception;
|
2009-08-03 06:17:15 +04:00
|
|
|
}
|
2005-04-17 02:20:36 +04:00
|
|
|
goto handle_kernel_fault;
|
|
|
|
|
|
|
|
|
|
intr_or_no_mm:
|
|
|
|
|
insn = get_fault_insn(regs, 0);
|
|
|
|
|
goto handle_kernel_fault;
|
|
|
|
|
|
|
|
|
|
do_sigbus:
|
|
|
|
|
insn = get_fault_insn(regs, insn);
|
2020-06-09 07:33:25 +03:00
|
|
|
mmap_read_unlock(mm);
|
2005-04-17 02:20:36 +04:00
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Send a sigbus, regardless of whether we were in kernel
|
|
|
|
|
* or user mode.
|
|
|
|
|
*/
|
2014-04-29 10:52:11 +04:00
|
|
|
do_fault_siginfo(BUS_ADRERR, SIGBUS, regs, address, insn, fault_code);
|
2005-04-17 02:20:36 +04:00
|
|
|
|
|
|
|
|
/* Kernel mode? Handle exceptions or die */
|
|
|
|
|
if (regs->tstate & TSTATE_PRIV)
|
|
|
|
|
goto handle_kernel_fault;
|
|
|
|
|
}
|
