Revision tags: v5.1.4, v5.1.3, v5.1.2, v5.1.1, v5.0.14, v5.1, v5.0.13, v5.0.12, v5.0.11, v5.0.10, v5.0.9, v5.0.8, v5.0.7, v5.0.6, v5.0.5, v5.0.4, v5.0.3, v4.19.29, v5.0.2, v4.19.28, v5.0.1, v4.19.27, v5.0, v4.19.26, v4.19.25, v4.19.24, v4.19.23, v4.19.22, v4.19.21, v4.19.20 |
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#
f8eac901 |
| 05-Feb-2019 |
Eric W. Biederman <ebiederm@xmission.com> |
signal: Remove task parameter from force_sig_mceerr
All of the callers pass current into force_sig_mceer so remove the task parameter to make this obvious.
This also makes it clear that force_sig_m
signal: Remove task parameter from force_sig_mceerr
All of the callers pass current into force_sig_mceer so remove the task parameter to make this obvious.
This also makes it clear that force_sig_mceerr passes current into force_sig_info.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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Revision tags: v4.19.19, v4.19.18, v4.19.17, v4.19.16, v4.19.15, v4.19.14, v4.19.13, v4.19.12, v4.19.11, v4.19.10, v4.19.9, v4.19.8, v4.19.7, v4.19.6, v4.19.5, v4.19.4, v4.18.20, v4.19.3, v4.18.19, v4.19.2, v4.18.18, v4.18.17, v4.19.1, v4.19, v4.18.16, v4.18.15, v4.18.14, v4.18.13, v4.18.12, v4.18.11, v4.18.10, v4.18.9, v4.18.7, v4.18.6, v4.18.5, v4.17.18, v4.18.4, v4.18.3, v4.17.17 |
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#
50a7ca3c |
| 17-Aug-2018 |
Souptick Joarder <jrdr.linux@gmail.com> |
mm: convert return type of handle_mm_fault() caller to vm_fault_t
Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rath
mm: convert return type of handle_mm_fault() caller to vm_fault_t
Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type.
Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t")
In this patch all the caller of handle_mm_fault() are changed to return vm_fault_t type.
Link: http://lkml.kernel.org/r/20180617084810.GA6730@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Tony Luck <tony.luck@intel.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Michal Simek <monstr@monstr.eu> Cc: James Hogan <jhogan@kernel.org> Cc: Ley Foon Tan <lftan@altera.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: David S. Miller <davem@davemloft.net> Cc: Richard Weinberger <richard@nod.at> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Levin, Alexander (Sasha Levin)" <alexander.levin@verizon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Revision tags: v4.18.2, v4.17.16, v4.17.15, v4.18.1, v4.18, v4.17.14, v4.17.13, v4.17.12, v4.17.11, v4.17.10, v4.17.9, v4.17.8, v4.17.7, v4.17.6, v4.17.5, v4.17.4, v4.17.3, v4.17.2, v4.17.1, v4.17 |
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#
ccf75290 |
| 19-Apr-2018 |
Eric W. Biederman <ebiederm@xmission.com> |
signal/parisc: Use force_sig_fault where appropriate
Filling in struct siginfo before calling force_sig_info a tedious and error prone process, where once in a great while the wrong fields are fille
signal/parisc: Use force_sig_fault where appropriate
Filling in struct siginfo before calling force_sig_info a tedious and error prone process, where once in a great while the wrong fields are filled out, and siginfo has been inconsistently cleared.
Simplify this process by using the helper force_sig_fault. Which takes as a parameters all of the information it needs, ensures all of the fiddly bits of filling in struct siginfo are done properly and then calls force_sig_info.
In short about a 5 line reduction in code for every time force_sig_info is called, which makes the calling function clearer.
Cc: James Bottomley <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-parisc@vger.kernel.org Acked-by: Helge Deller <deller@gmx.de> # parisc Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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c2b0e0d3 |
| 19-Apr-2018 |
Eric W. Biederman <ebiederm@xmission.com> |
signal/parisc: Use force_sig_mceerr where appropriate
In do_page_fault where an mceerr is generated stop and call force_sig_mceerr. Keeping the mcerr handling logic out of the force_sig_info call be
signal/parisc: Use force_sig_mceerr where appropriate
In do_page_fault where an mceerr is generated stop and call force_sig_mceerr. Keeping the mcerr handling logic out of the force_sig_info call below.
This ensures that only and always in the mcerr case is lsb interesting.
This ensures setting set si_lsb in the future won't accidentally stomp another siginfo field in the non mcerr case.
Cc: James Bottomley <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-parisc@vger.kernel.org Acked-by: Helge Deller <deller@gmx.de> # parisc Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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#
3eb0f519 |
| 17-Apr-2018 |
Eric W. Biederman <ebiederm@xmission.com> |
signal: Ensure every siginfo we send has all bits initialized
Call clear_siginfo to ensure every stack allocated siginfo is properly initialized before being passed to the signal sending functions.
signal: Ensure every siginfo we send has all bits initialized
Call clear_siginfo to ensure every stack allocated siginfo is properly initialized before being passed to the signal sending functions.
Note: It is not safe to depend on C initializers to initialize struct siginfo on the stack because C is allowed to skip holes when initializing a structure.
The initialization of struct siginfo in tracehook_report_syscall_exit was moved from the helper user_single_step_siginfo into tracehook_report_syscall_exit itself, to make it clear that the local variable siginfo gets fully initialized.
In a few cases the scope of struct siginfo has been reduced to make it clear that siginfo siginfo is not used on other paths in the function in which it is declared.
Instances of using memset to initialize siginfo have been replaced with calls clear_siginfo for clarity.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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Revision tags: v4.16, v4.15, v4.13.16, v4.14, v4.13.5 |
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#
606f95e4 |
| 21-Sep-2017 |
Helge Deller <deller@gmx.de> |
parisc: Add HWPOISON page fault handler code
Commit 24587380f61d ("parisc: Add MADV_HWPOISON and MADV_SOFT_OFFLINE") added the necessary constants to handle hardware-poisoning. Those were needed to
parisc: Add HWPOISON page fault handler code
Commit 24587380f61d ("parisc: Add MADV_HWPOISON and MADV_SOFT_OFFLINE") added the necessary constants to handle hardware-poisoning. Those were needed to support the page deallocation feature from firmware.
But I completely missed to add the relevant fault handler code. This now showed up when I ran the madvise07 testcase from the Linux Test Project, which failed with a kernel BUG at arch/parisc/mm/fault.c:320.
With this patch the parisc kernel now behaves like other platforms and gives the same kernel syslog warnings when poisoning pages.
Signed-off-by: Helge Deller <deller@gmx.de>
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Revision tags: v4.13, v4.12 |
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#
24746231 |
| 02-Jul-2017 |
Helge Deller <deller@gmx.de> |
parisc: Report SIGSEGV instead of SIGBUS when running out of stack
When a process runs out of stack the parisc kernel wrongly faults with SIGBUS instead of the expected SIGSEGV signal.
This example
parisc: Report SIGSEGV instead of SIGBUS when running out of stack
When a process runs out of stack the parisc kernel wrongly faults with SIGBUS instead of the expected SIGSEGV signal.
This example shows how the kernel faults: do_page_fault() command='a.out' type=15 address=0xfaac2000 in libc-2.24.so[f8308000+16c000] trap #15: Data TLB miss fault, vm_start = 0xfa2c2000, vm_end = 0xfaac2000
The vma->vm_end value is the first address which does not belong to the vma, so adjust the check to include vma->vm_end to the range for which to send the SIGSEGV signal.
This patch unbreaks building the debian libsigsegv package.
Cc: stable@vger.kernel.org Signed-off-by: Helge Deller <deller@gmx.de>
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#
b752c7b2 |
| 08-Jun-2017 |
Helge Deller <deller@gmx.de> |
parisc: Avoid zeroing gr[0] in fixup_exception()
Register gr[0] holds the PSW in interrupt context. It's absolutely unlikely that the compiler will use register zero in a get_user() call, but better
parisc: Avoid zeroing gr[0] in fixup_exception()
Register gr[0] holds the PSW in interrupt context. It's absolutely unlikely that the compiler will use register zero in a get_user() call, but better BUG on such a case in fixup_exception() anyway.
Signed-off-by: Helge Deller <deller@gmx.de>
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Revision tags: v4.10.17, v4.10.16, v4.10.15, v4.10.14, v4.10.13, v4.10.12, v4.10.11, v4.10.10, v4.10.9 |
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#
c3e5523f |
| 02-Apr-2017 |
Helge Deller <deller@gmx.de> |
parisc: Drop per_cpu uaccess related exception_data struct
The last users have been migrated off by commits d19f5e41b344 ("parisc: Clean up fixup routines for get_user()/put_user()") and 554bfeceb8a
parisc: Drop per_cpu uaccess related exception_data struct
The last users have been migrated off by commits d19f5e41b344 ("parisc: Clean up fixup routines for get_user()/put_user()") and 554bfeceb8a2 ("parisc: Fix access fault handling in pa_memcpy()").
Signed-off-by: Helge Deller <deller@gmx.de>
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Revision tags: v4.10.8, v4.10.7, v4.10.6 |
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#
d19f5e41 |
| 25-Mar-2017 |
Helge Deller <deller@gmx.de> |
parisc: Clean up fixup routines for get_user()/put_user()
Al Viro noticed that userspace accesses via get_user()/put_user() can be simplified a lot with regard to usage of the exception handling.
T
parisc: Clean up fixup routines for get_user()/put_user()
Al Viro noticed that userspace accesses via get_user()/put_user() can be simplified a lot with regard to usage of the exception handling.
This patch implements a fixup routine for get_user() and put_user() in such that the exception handler will automatically load -EFAULT into the register %r8 (the error value) in case on a fault on userspace. Additionally the fixup routine will zero the target register on fault in case of a get_user() call. The target register is extracted out of the faulting assembly instruction.
This patch brings a few benefits over the old implementation: 1. Exception handling gets much cleaner, easier and smaller in size. 2. Helper functions like fixup_get_user_skip_1 (all of fixup.S) can be dropped. 3. No need to hardcode %r9 as target register for get_user() any longer. This helps the compiler register allocator and thus creates less assembler statements. 4. No dependency on the exception_data contents any longer. 5. Nested faults will be handled cleanly.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Cc: <stable@vger.kernel.org> # v4.9+ Signed-off-by: Helge Deller <deller@gmx.de>
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Revision tags: v4.10.5, v4.10.4, v4.10.3, v4.10.2, v4.10.1, v4.10 |
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#
b17b0153 |
| 08-Feb-2017 |
Ingo Molnar <mingo@kernel.org> |
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>
We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which will have to be picked up fro
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>
We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/debug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
8351badf |
| 08-Feb-2017 |
Dan Carpenter <dan.carpenter@oracle.com> |
parisc: fix a printk
We want to do a pr_cont() here and not a pr_warn().
Fixes: b391667eb45a ("parisc: Report trap type as human readable string") Signed-off-by: Dan Carpenter <dan.carpenter@oracle
parisc: fix a printk
We want to do a pr_cont() here and not a pr_warn().
Fixes: b391667eb45a ("parisc: Report trap type as human readable string") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Helge Deller <deller@gmx.de>
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#
b4a9eb4c |
| 02-Jan-2017 |
Helge Deller <deller@gmx.de> |
parisc: Add line-break when printing segfault info
Add a leading line break else printed line gets too long.
Signed-off-by: Helge Deller <deller@gmx.de> Cc: <stable@vger.kernel.org> # v4.9
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Revision tags: v4.9, openbmc-4.4-20161121-1, v4.4.33, v4.4.32, v4.4.31, v4.4.30, v4.4.29, v4.4.28, v4.4.27, v4.7.10, openbmc-4.4-20161021-1, v4.7.9, v4.4.26, v4.7.8, v4.4.25 |
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#
0a862485 |
| 11-Oct-2016 |
Helge Deller <deller@gmx.de> |
parisc: Show trap name in kernel crash
Show the real trap name when the kernel crashes.
Signed-off-by: Helge Deller <deller@gmx.de>
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Revision tags: v4.4.24, v4.7.7, v4.8, v4.4.23, v4.7.6, v4.7.5, v4.4.22 |
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#
a38671d6 |
| 19-Sep-2016 |
Paul Gortmaker <paul.gortmaker@windriver.com> |
parisc: Migrate exception table users off module.h and onto extable.h
This file was only including module.h for exception table related functions. We've now separated that content out into its own
parisc: Migrate exception table users off module.h and onto extable.h
This file was only including module.h for exception table related functions. We've now separated that content out into its own file "extable.h" so now move over to that and avoid all the extra header content in module.h that we don't really need to compile this file.
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-parisc@vger.kernel.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Helge Deller <deller@gmx.de>
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#
b391667e |
| 24-Sep-2016 |
Helge Deller <deller@gmx.de> |
parisc: Report trap type as human readable string
When faulting on some trap, the kernel currently reports in dmesg:
do_page_fault() command='perl' type=6 address=0xbe400403 in libcrypt-2.24.so[f9
parisc: Report trap type as human readable string
When faulting on some trap, the kernel currently reports in dmesg:
do_page_fault() command='perl' type=6 address=0xbe400403 in libcrypt-2.24.so[f9086000+9000] vm_start = 0x00922000, vm_end = 0x00aed000
With this change the trap type additionally gets reported as human readable string which makes it simpler to recognize the type of problem:
do_page_fault() command='perl' type=6 address=0xbe400403 in libcrypt-2.24.so[f9086000+9000] trap #6: Instruction TLB miss fault, vm_start = 0x00922000, vm_end = 0x00aed000
Signed-off-by: Helge Deller <deller@gmx.de>
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Revision tags: v4.4.21, v4.7.4, v4.7.3, v4.4.20, v4.7.2, v4.4.19, openbmc-4.4-20160819-1, v4.7.1, v4.4.18, v4.4.17, openbmc-4.4-20160804-1, v4.4.16 |
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#
dcddffd4 |
| 26-Jul-2016 |
Kirill A. Shutemov <kirill.shutemov@linux.intel.com> |
mm: do not pass mm_struct into handle_mm_fault
We always have vma->vm_mm around.
Link: http://lkml.kernel.org/r/1466021202-61880-8-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Kiri
mm: do not pass mm_struct into handle_mm_fault
We always have vma->vm_mm around.
Link: http://lkml.kernel.org/r/1466021202-61880-8-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Revision tags: v4.7, openbmc-4.4-20160722-1, openbmc-20160722-1, openbmc-20160713-1, v4.4.15, v4.6.4, v4.6.3, v4.4.14, v4.6.2, v4.4.13, openbmc-20160606-1, v4.6.1, v4.4.12, openbmc-20160521-1, v4.4.11, openbmc-20160518-1, v4.6, v4.4.10, openbmc-20160511-1, openbmc-20160505-1, v4.4.9, v4.4.8, v4.4.7 |
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#
2ef4dfd9 |
| 08-Apr-2016 |
Helge Deller <deller@gmx.de> |
parisc: Unbreak handling exceptions from kernel modules
Handling exceptions from modules never worked on parisc. It was just masked by the fact that exceptions from modules don't happen during norma
parisc: Unbreak handling exceptions from kernel modules
Handling exceptions from modules never worked on parisc. It was just masked by the fact that exceptions from modules don't happen during normal use.
When a module triggers an exception in get_user() we need to load the main kernel dp value before accessing the exception_data structure, and afterwards restore the original dp value of the module on exit.
Noticed-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Helge Deller <deller@gmx.de> Cc: stable@vger.kernel.org
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Revision tags: openbmc-20160329-2, openbmc-20160329-1 |
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#
0de79858 |
| 23-Mar-2016 |
Helge Deller <deller@gmx.de> |
parisc: Use generic extable search and sort routines
Switch to the generic extable search and sort routines which were introduced with commit a272858 from Ard Biesheuvel. This saves quite some memor
parisc: Use generic extable search and sort routines
Switch to the generic extable search and sort routines which were introduced with commit a272858 from Ard Biesheuvel. This saves quite some memory in the vmlinux binary with the 64bit kernel.
Signed-off-by: Helge Deller <deller@gmx.de>
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Revision tags: openbmc-20160321-1, v4.4.6, v4.5, v4.4.5, v4.4.4, v4.4.3, openbmc-20160222-1, v4.4.2, openbmc-20160212-1, openbmc-20160210-1, openbmc-20160202-2, openbmc-20160202-1, v4.4.1, openbmc-20160127-1, openbmc-20160120-1, v4.4, openbmc-20151217-1, openbmc-20151210-1, openbmc-20151202-1, openbmc-20151123-1, openbmc-20151118-1, openbmc-20151104-1, v4.3, openbmc-20151102-1, openbmc-20151028-1, v4.3-rc1 |
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#
699817c3 |
| 02-Sep-2015 |
Helge Deller <deller@gmx.de> |
parisc: Additionally check for in_atomic() in page fault handler
Craig Estey noticed that we didn't checked for in_atomic() in our page fault handler like other architectures. This commit adds this
parisc: Additionally check for in_atomic() in page fault handler
Craig Estey noticed that we didn't checked for in_atomic() in our page fault handler like other architectures. This commit adds this check by using faulthandler_disabled() which includes a check for pagefault_disabled() and in_atomic().
Reported-by: Craig Estey <cae370@gmail.com> Signed-off-by: Helge Deller <deller@gmx.de>
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Revision tags: v4.2, v4.2-rc8, v4.2-rc7, v4.2-rc6, v4.2-rc5, v4.2-rc4, v4.2-rc3, v4.2-rc2, v4.2-rc1, v4.1, v4.1-rc8, v4.1-rc7, v4.1-rc6, v4.1-rc5, v4.1-rc4 |
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#
70ffdb93 |
| 11-May-2015 |
David Hildenbrand <dahi@linux.vnet.ibm.com> |
mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler
Introduce faulthandler_disabled() and use it to check for irq context and disabled pagefaults (via pagefault_d
mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler
Introduce faulthandler_disabled() and use it to check for irq context and disabled pagefaults (via pagefault_disable()) in the pagefault handlers.
Please note that we keep the in_atomic() checks in place - to detect whether in irq context (in which case preemption is always properly disabled).
In contrast, preempt_disable() should never be used to disable pagefaults. With !CONFIG_PREEMPT_COUNT, preempt_disable() doesn't modify the preempt counter, and therefore the result of in_atomic() differs. We validate that condition by using might_fault() checks when calling might_sleep().
Therefore, add a comment to faulthandler_disabled(), describing why this is needed.
faulthandler_disabled() and pagefault_disable() are defined in linux/uaccess.h, so let's properly add that include to all relevant files.
This patch is based on a patch from Thomas Gleixner.
Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: David.Laight@ACULAB.COM Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: airlied@linux.ie Cc: akpm@linux-foundation.org Cc: benh@kernel.crashing.org Cc: bigeasy@linutronix.de Cc: borntraeger@de.ibm.com Cc: daniel.vetter@intel.com Cc: heiko.carstens@de.ibm.com Cc: herbert@gondor.apana.org.au Cc: hocko@suse.cz Cc: hughd@google.com Cc: mst@redhat.com Cc: paulus@samba.org Cc: ralf@linux-mips.org Cc: schwidefsky@de.ibm.com Cc: yang.shi@windriver.com Link: http://lkml.kernel.org/r/1431359540-32227-7-git-send-email-dahi@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Revision tags: v4.1-rc3, v4.1-rc2, v4.1-rc1, v4.0, v4.0-rc7, v4.0-rc6, v4.0-rc5, v4.0-rc4, v4.0-rc3, v4.0-rc2, v4.0-rc1, v3.19, v3.19-rc7 |
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#
33692f27 |
| 29-Jan-2015 |
Linus Torvalds <torvalds@linux-foundation.org> |
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 calle
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>
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Revision tags: v3.19-rc6, v3.19-rc5, v3.19-rc4, v3.19-rc3, v3.19-rc2, v3.19-rc1, v3.18, v3.18-rc7, v3.18-rc6, v3.18-rc5, v3.18-rc4, v3.18-rc3, v3.18-rc2, v3.18-rc1, v3.17, v3.17-rc7, v3.17-rc6, v3.17-rc5, v3.17-rc4, v3.17-rc3, v3.17-rc2, v3.17-rc1, v3.16, v3.16-rc7, v3.16-rc6, v3.16-rc5, v3.16-rc4, v3.16-rc3, v3.16-rc2, v3.16-rc1, v3.15, v3.15-rc8, v3.15-rc7, v3.15-rc6, v3.15-rc5 |
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fef47e2a |
| 05-May-2014 |
Helge Deller <deller@gmx.de> |
parisc: ratelimit userspace segfault printing
Ratelimit printing of userspace segfaults and make it runtime configurable via the /proc/sys/debug/exception-trace variable. This should resolve syslog
parisc: ratelimit userspace segfault printing
Ratelimit printing of userspace segfaults and make it runtime configurable via the /proc/sys/debug/exception-trace variable. This should resolve syslog from growing way too fast and thus prevents possible system service attacks.
Signed-off-by: Helge Deller <deller@gmx.de> Cc: stable@vger.kernel.org # 3.13+
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Revision tags: v3.15-rc4, v3.15-rc3, v3.15-rc2, v3.15-rc1, v3.14, v3.14-rc8, v3.14-rc7, v3.14-rc6, v3.14-rc5, v3.14-rc4, v3.14-rc3 |
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#
496252f7 |
| 14-Feb-2014 |
Christoph Lameter <cl@linux.com> |
parisc: Replace __get_cpu_var uses for address calculation
Convert to the use of this_cpu_ptr().
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-parisc
parisc: Replace __get_cpu_var uses for address calculation
Convert to the use of this_cpu_ptr().
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-parisc@vger.kernel.org Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Helge Deller <deller@gmx.de>
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Revision tags: v3.14-rc2, v3.14-rc1, v3.13, v3.13-rc8, v3.13-rc7, v3.13-rc6, v3.13-rc5, v3.13-rc4, v3.13-rc3, v3.13-rc2, v3.13-rc1 |
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#
49d1cb2b |
| 18-Nov-2013 |
Helge Deller <deller@gmx.de> |
parisc: improve SIGBUS/SIGSEGV error reporting
This patch fixes most of the Linux Test Project testcases, e.g. fstat05.
Signed-off-by: Helge Deller <deller@gmx.de>
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