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* parisc: Unbreak handling exceptions from kernel modulesHelge Deller2016-04-081-0/+1
| | | | | | | | | | | | | | 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
* parisc: Use generic extable search and sort routinesHelge Deller2016-03-231-7/+2
| | | | | | | | 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>
* parisc: Additionally check for in_atomic() in page fault handlerHelge Deller2015-09-081-1/+1
| | | | | | | | | | 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>
* mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in ↵David Hildenbrand2015-05-191-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* vm: add VM_FAULT_SIGSEGV handling supportLinus Torvalds2015-01-291-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Merge branch 'parisc-3.15-4' of ↵Linus Torvalds2014-05-201-14/+30
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux 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
| * parisc: ratelimit userspace segfault printingHelge Deller2014-05-151-14/+30
| | | | | | | | | | | | | | | | | | | | 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+
* | parisc: Replace __get_cpu_var uses for address calculationChristoph Lameter2014-04-031-1/+1
|/ | | | | | | | | | 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>
* parisc: improve SIGBUS/SIGSEGV error reportingHelge Deller2013-11-191-2/+20
| | | | | | This patch fixes most of the Linux Test Project testcases, e.g. fstat05. Signed-off-by: Helge Deller <deller@gmx.de>
* parisc: signal fixup - SIGBUS vs. SIGSEGVHelge Deller2013-11-071-4/+14
| | | | | | | | | | Clean up code to send correct signal on invalid memory accesses: Send SIGBUS instead of SIGSEGV for memory accesses outside of mmap'ed areas This fixes the mmap13 testcase from the Linux Test Project. Signed-off-by: Helge Deller <deller@gmx.de>
* parisc: provide macro to create exception table entriesHelge Deller2013-11-071-0/+6
| | | | | | | | | | | 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 <deller@gmx.de>
* parisc: optimize variable initialization in do_page_faultJohn David Anglin2013-10-131-5/+10
| | | | | | | | | | 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 <dave.anglin@bell.net> Signed-off-by: Helge Deller <deller@gmx.de>
* arch/parisc/mm/fault.c: fix uninitialized variable usageFelipe Pena2013-09-301-2/+3
| | | | | | | | | | | | | | | 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 <felipensp@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* arch: mm: pass userspace fault flag to generic fault handlerJohannes Weiner2013-09-121-2/+5
| | | | | | | | | | | | | | | | | | | | 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 <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* parisc/mm/fault.c: Port OOM changes to do_page_faultKautuk Consul2013-02-201-5/+25
| | | | | | | | | | | | | | | | | | 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 <consul.kautuk@gmail.com> Signed-off-by: Helge Deller <deller@gmx.de>
* parisc: invoke oom-killer from page faultNick Piggin2010-05-301-4/+3
| | | | | | | | | | | | 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 <npiggin@suse.de> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
* parisc: remove CVS keywordsAlexander Beregalov2009-07-031-2/+1
| | | | | | | Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com> Acked-by: Matthew Wilcox <willy@linux.intel.com> Acked-by: Grant Grundler <grundler@parisc-linux.org> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
* Move FAULT_FLAG_xyz into handle_mm_fault() callersLinus Torvalds2009-06-211-1/+1
| | | | | | | | | | 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 <torvalds@linux-foundation.org>
* parisc: fix kernel crash (protection id trap) when compiling ruby1.9Kyle McMartin2009-01-051-27/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <kyle@mcmartin.ca>
* Use helpers to obtain task pid in printks (arch code)Alexey Dobriyan2007-10-191-1/+1
| | | | | | | | | | | | | | | 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 <adobriyan@openvz.org> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* During VM oom condition, kill all threads in process groupWill Schmidt2007-10-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <will_schmidt@vnet.ibm.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ian Molton <spyro@f2s.com> Cc: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: Mikael Starvik <starvik@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Andi Kleen <ak@suse.de> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Matthew Wilcox <willy@debian.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Richard Curnow <rc@rc0.org.uk> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: fault feedback #2Nick Piggin2007-07-191-11/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <npiggin@suse.de> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ian Molton <spyro@f2s.com> Cc: Bryan Wu <bryan.wu@analog.com> Cc: Mikael Starvik <starvik@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Greg Ungerer <gerg@uclinux.org> Cc: Matthew Wilcox <willy@debian.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Richard Curnow <rc@rc0.org.uk> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Chris Zankel <chris@zankel.net> Acked-by: Kyle McMartin <kyle@mcmartin.ca> Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Acked-by: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> [ Still apparently needs some ARM and PPC loving - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PARISC] whitespace cleanups and unify 32/64bit user-access assembler inlinesHelge Deller2007-02-171-4/+0
| | | | | Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
* [PATCH] mm: arch do_page_fault() vs in_atomic()Peter Zijlstra2006-12-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 - good Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PARISC] Misc. janitorial workHelge Deller2006-04-211-1/+1
| | | | | | | | Fix a spelling mistake, add a KERN_INFO flag, and fix some whitespace uglies. Signed-off-by: Helge Deller <deller@parisc-linux.org> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
* It wasn't just x86-64 that had hardcoded VM_FAULT_xxx numbersLinus Torvalds2005-08-041-6/+6
| | | | Fix up arm26, cris, frv, m68k, parisc and sh64 too..
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+271
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!
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