23 Sep, 2017
1 commit
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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
03 Jul, 2017
1 commit
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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 = 0xfaac2000The 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
09 Jun, 2017
1 commit
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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
10 May, 2017
1 commit
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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
30 Mar, 2017
1 commit
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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
Cc: # v4.9+
Signed-off-by: Helge Deller
04 Mar, 2017
1 commit
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Pull parisc fixes and cleanups from Helge Deller:
"Nothing really important in this patchset: fix resource leaks in error
paths, coding style cleanups and code removal"* 'parisc-4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Remove flush_user_dcache_range and flush_user_icache_range
parisc: fix a printk
parisc: ccio-dma: Handle return NULL error from ioremap_nocache
parisc: Define access_ok() as macro
parisc: eisa: Fix resource leaks in error paths
parisc: eisa: Remove coding style errors
02 Mar, 2017
1 commit
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We are going to split out of , which
will have to be picked up from other headers and a couple of .c files.Create a trivial placeholder file that just
maps to 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
Cc: Mike Galbraith
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar
26 Feb, 2017
1 commit
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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
Signed-off-by: Helge Deller
03 Jan, 2017
1 commit
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Add a leading line break else printed line gets too long.
Signed-off-by: Helge Deller
Cc: # v4.9
12 Oct, 2016
1 commit
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Show the real trap name when the kernel crashes.
Signed-off-by: Helge Deller
08 Oct, 2016
1 commit
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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"
Cc: Helge Deller
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Paul Gortmaker
Signed-off-by: Helge Deller
25 Sep, 2016
1 commit
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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 = 0x00aed000With 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 = 0x00aed000Signed-off-by: Helge Deller
27 Jul, 2016
1 commit
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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
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
09 Apr, 2016
1 commit
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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
Signed-off-by: Helge Deller
Cc: stable@vger.kernel.org
23 Mar, 2016
1 commit
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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
08 Sep, 2015
1 commit
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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
Signed-off-by: Helge Deller
19 May, 2015
1 commit
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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
Signed-off-by: David Hildenbrand
Signed-off-by: Peter Zijlstra (Intel)
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Thomas Gleixner
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
30 Jan, 2015
1 commit
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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
Tested-by: Jan Engelhardt
Acked-by: Heiko Carstens # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds
20 May, 2014
1 commit
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Pull parisc fixes from Helge Deller:
"There are two patches in here:The first patch greatly improves latency and corrects the memory
ordering in our light-weight atomic locking syscall.The second patch ratelimits printing of userspace segfaults in the
same way as it's done on other platforms. This fixes a possible DOS
on parisc since it prevents the syslog to grow too fast. For example,
when the debian acl2 package was built on our debian buildd servers,
this package produced lots of gigabytes in syslog in very short time
and thus filled our harddisks, which then turned the server nearly
completely unaccessible and unresponsive"* 'parisc-3.15-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Improve LWS-CAS performance
parisc: ratelimit userspace segfault printing
16 May, 2014
1 commit
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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
Cc: stable@vger.kernel.org # 3.13+
04 Apr, 2014
1 commit
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Convert to the use of this_cpu_ptr().
Cc: "James E.J. Bottomley"
Cc: Helge Deller
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Christoph Lameter
Signed-off-by: Helge Deller
20 Nov, 2013
1 commit
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This patch fixes most of the Linux Test Project testcases, e.g. fstat05.
Signed-off-by: Helge Deller
08 Nov, 2013
2 commits
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Clean up code to send correct signal on invalid memory accesses:
Send SIGBUS instead of SIGSEGV for memory accesses outside of mmap'ed
areasThis fixes the mmap13 testcase from the Linux Test Project.
Signed-off-by: Helge Deller
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Provide a macro ASM_EXCEPTIONTABLE_ENTRY() to create exception table
entries and convert all open-coded places to use that macro.This patch is a first step toward creating a exception table which only
holds 32bit pointers even on a 64bit kernel. That way in my own kernel
I was able to reduce the in-kernel exception table from 44kB to 22kB.Signed-off-by: Helge Deller
13 Oct, 2013
1 commit
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The attached change defers the initialization of the variables tsk, mm
and flags until they are needed. As a result, the code won't crash if a
kernel probe is done with a corrupt context and the code will be better
optimized.Signed-off-by: John David Anglin
Signed-off-by: Helge Deller
01 Oct, 2013
1 commit
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The FAULT_FLAG_WRITE flag has been set based on uninitialized variable.
Fixes a regression added by commit 759496ba6407 ("arch: mm: pass
userspace fault flag to generic fault handler")Signed-off-by: Felipe Pena
Cc: Johannes Weiner
Cc: Michal Hocko
Cc: "James E.J. Bottomley"
Cc: Helge Deller
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
13 Sep, 2013
1 commit
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Unlike global OOM handling, memory cgroup code will invoke the OOM killer
in any OOM situation because it has no way of telling faults occuring in
kernel context - which could be handled more gracefully - from
user-triggered faults.Pass a flag that identifies faults originating in user space from the
architecture-specific fault handlers to generic code so that memcg OOM
handling can be improved.Signed-off-by: Johannes Weiner
Reviewed-by: Michal Hocko
Cc: David Rientjes
Cc: KAMEZAWA Hiroyuki
Cc: azurIt
Cc: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
21 Feb, 2013
1 commit
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Commit d065bd810b6deb67d4897a14bfe21f8eb526ba99
(mm: retry page fault when blocking on disk transfer) and
commit 37b23e0525d393d48a7d59f870b3bc061a30ccdb
(x86,mm: make pagefault killable)The above commits introduced changes into the x86 pagefault handler
for making the page fault handler retryable as well as killable.These changes reduce the mmap_sem hold time, which is crucial
during OOM killer invocation.Port these changes to parisc.
Signed-off-by: Kautuk Consul
Signed-off-by: Helge Deller
30 May, 2010
1 commit
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As explained in commit 1c0fe6e3bd, we want to call the architecture independent
oom killer when getting an unexplained OOM from handle_mm_fault, rather than
simply killing current.Cc: linux-parisc@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Signed-off-by: Nick Piggin
Acked-by: David Rientjes
Signed-off-by: Kyle McMartin
03 Jul, 2009
1 commit
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Signed-off-by: Alexander Beregalov
Acked-by: Matthew Wilcox
Acked-by: Grant Grundler
Signed-off-by: Kyle McMartin
22 Jun, 2009
1 commit
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This allows the callers to now pass down the full set of FAULT_FLAG_xyz
flags to handle_mm_fault(). All callers have been (mechanically)
converted to the new calling convention, there's almost certainly room
for architectures to clean up their code and then add FAULT_FLAG_RETRY
when that support is added.Signed-off-by: Linus Torvalds
06 Jan, 2009
1 commit
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On Wed, Dec 17, 2008 at 11:46:05PM +0100, Helge Deller wrote:
>Honestly, I can't decide whether to apply this. It really should never
happen in the kernel, since the kernel can guarantee it won't get the
access rights failure (highest privilege level, and can set %sr and
%protid to whatever it wants.)It really genuinely is a bug that probably should panic the kernel. The
only precedent I can easily see is x86 fixing up a bad iret with a
general protection fault, which is more or less analogous to code 27
here.On the other hand, taking the exception on a userspace access really
isn't all that critical, and there's fundamentally little reason for the
kernel not to SIGSEGV the process, and continue...Argh.
(btw, I've instrumented my do_sys_poll with a pile of assertions that
%cr8 << 1 == %sr3 == current->mm.context... let's see if where we're
getting corrupted is deterministic, though, I would guess that it won't
be.)Signed-off-by: Kyle McMartin
20 Oct, 2007
1 commit
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One of the easiest things to isolate is the pid printed in kernel log.
There was a patch, that made this for arch-independent code, this one makes
so for arch/xxx files.It took some time to cross-compile it, but hopefully these are all the
printks in arch code.Signed-off-by: Alexey Dobriyan
Signed-off-by: Pavel Emelyanov
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
17 Oct, 2007
1 commit
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We have had complaints where a threaded application is left in a bad state
after one of it's threads is killed when we hit a VM: out_of_memory
condition.Killing just one of the process threads can leave the application in a bad
state, whereas killing the entire process group would allow for the
application to restart, or be otherwise handled, and makes it very obvious
that something has gone wrong.This change allows the entire process group to be taken down, rather
than just the one thread.Signed-off-by: Will Schmidt
Cc: Richard Henderson
Cc: Ivan Kokshaysky
Cc: Russell King
Cc: Ian Molton
Cc: Haavard Skinnemoen
Cc: Mikael Starvik
Cc: David Howells
Cc: Andi Kleen
Cc: "Luck, Tony"
Cc: Hirokazu Takata
Cc: Geert Uytterhoeven
Cc: Roman Zippel
Cc: Ralf Baechle
Cc: Kyle McMartin
Cc: Matthew Wilcox
Cc: Paul Mackerras
Cc: Benjamin Herrenschmidt
Cc: Heiko Carstens
Cc: Martin Schwidefsky
Cc: Paul Mundt
Cc: Kazumoto Kojima
Cc: Richard Curnow
Cc: William Lee Irwin III
Cc: "David S. Miller"
Cc: Chris Zankel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
20 Jul, 2007
1 commit
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This patch completes Linus's wish that the fault return codes be made into
bit flags, which I agree makes everything nicer. This requires requires
all handle_mm_fault callers to be modified (possibly the modifications
should go further and do things like fault accounting in handle_mm_fault --
however that would be for another patch).[akpm@linux-foundation.org: fix alpha build]
[akpm@linux-foundation.org: fix s390 build]
[akpm@linux-foundation.org: fix sparc build]
[akpm@linux-foundation.org: fix sparc64 build]
[akpm@linux-foundation.org: fix ia64 build]
Signed-off-by: Nick Piggin
Cc: Richard Henderson
Cc: Ivan Kokshaysky
Cc: Russell King
Cc: Ian Molton
Cc: Bryan Wu
Cc: Mikael Starvik
Cc: David Howells
Cc: Yoshinori Sato
Cc: "Luck, Tony"
Cc: Hirokazu Takata
Cc: Geert Uytterhoeven
Cc: Roman Zippel
Cc: Greg Ungerer
Cc: Matthew Wilcox
Cc: Paul Mackerras
Cc: Benjamin Herrenschmidt
Cc: Heiko Carstens
Cc: Martin Schwidefsky
Cc: Paul Mundt
Cc: Kazumoto Kojima
Cc: Richard Curnow
Cc: William Lee Irwin III
Cc: "David S. Miller"
Cc: Jeff Dike
Cc: Paolo 'Blaisorblade' Giarrusso
Cc: Miles Bader
Cc: Chris Zankel
Acked-by: Kyle McMartin
Acked-by: Haavard Skinnemoen
Acked-by: Ralf Baechle
Acked-by: Andi Kleen
Signed-off-by: Andrew Morton
[ Still apparently needs some ARM and PPC loving - Linus ]
Signed-off-by: Linus Torvalds
17 Feb, 2007
1 commit
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Signed-off-by: Helge Deller
Signed-off-by: Kyle McMartin
08 Dec, 2006
1 commit
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In light of the recent pagefault and filemap_copy_from_user work I've gone
through all the arch pagefault handlers to make sure the inc_preempt_count()
'feature' works as expected.Several sections of code (including the new filemap_copy_from_user) rely on
the fact that faults do not take locks under increased preempt count.arch/x86_64 - good
arch/powerpc - good
arch/cris - fixed
arch/i386 - good
arch/parisc - fixed
arch/sh - good
arch/sparc - good
arch/s390 - good
arch/m68k - fixed
arch/ppc - good
arch/alpha - fixed
arch/mips - good
arch/sparc64 - good
arch/ia64 - good
arch/arm - fixed
arch/um - good
arch/avr32 - good
arch/h8300 - NA
arch/m32r - good
arch/v850 - good
arch/frv - fixed
arch/m68knommu - NA
arch/arm26 - fixed
arch/sh64 - fixed
arch/xtensa - goodSigned-off-by: Peter Zijlstra
Acked-by: Nick Piggin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
22 Apr, 2006
1 commit
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Fix a spelling mistake, add a KERN_INFO flag, and fix some whitespace
uglies.Signed-off-by: Helge Deller
Signed-off-by: Kyle McMartin
04 Aug, 2005
1 commit
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Fix up arm26, cris, frv, m68k, parisc and sh64 too..
17 Apr, 2005
1 commit
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Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.Let it rip!
