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* arch: mm: pass userspace fault flag to generic fault handlerJohannes Weiner2013-09-1328-64/+134
| | | | | | | | | | | | | | | | | | | | 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>
* arch: mm: do not invoke OOM killer on kernel fault OOMJohannes Weiner2013-09-136-22/+26
| | | | | | | | | | | | | | | | | Kernel faults are expected to handle OOM conditions gracefully (gup, uaccess etc.), so they should never invoke the OOM killer. Reserve this for faults triggered in user context when it is the only option. Most architectures already do this, fix up the remaining few. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* arch: mm: remove obsolete init OOM protectionJohannes Weiner2013-09-133-17/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The memcg code can trap tasks in the context of the failing allocation until an OOM situation is resolved. They can hold all kinds of locks (fs, mm) at this point, which makes it prone to deadlocking. This series converts memcg OOM handling into a two step process that is started in the charge context, but any waiting is done after the fault stack is fully unwound. Patches 1-4 prepare architecture handlers to support the new memcg requirements, but in doing so they also remove old cruft and unify out-of-memory behavior across architectures. Patch 5 disables the memcg OOM handling for syscalls, readahead, kernel faults, because they can gracefully unwind the stack with -ENOMEM. OOM handling is restricted to user triggered faults that have no other option. Patch 6 reworks memcg's hierarchical OOM locking to make it a little more obvious wth is going on in there: reduce locked regions, rename locking functions, reorder and document. Patch 7 implements the two-part OOM handling such that tasks are never trapped with the full charge stack in an OOM situation. This patch: Back before smart OOM killing, when faulting tasks were killed directly on allocation failures, the arch-specific fault handlers needed special protection for the init process. Now that all fault handlers call into the generic OOM killer (see commit 609838cfed97: "mm: invoke oom-killer from remaining unconverted page fault handlers"), which already provides init protection, the arch-specific leftovers can be removed. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc bits] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* s390/vmcore: use vmcore for zfcpdumpMichael Holzheu2013-09-123-19/+107
| | | | | | | | | | | | | Modify the s390 copy_oldmem_page() and remap_oldmem_pfn_range() function for zfcpdump to read from the HSA memory if memory below HSA_SIZE bytes is requested. Otherwise real memory is used. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Jan Willeke <willeke@de.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* s390/vmcore: implement remap_oldmem_pfn_range for s390Jan Willeke2013-09-121-0/+26
| | | | | | | | | | | | | Introduce the s390 specific way to map pages from oldmem. The memory area below OLDMEM_SIZE is mapped with offset OLDMEM_BASE. The other old memory is mapped directly. Signed-off-by: Jan Willeke <willeke@de.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* s390/vmcore: use ELF header in new memory featureMichael Holzheu2013-09-121-27/+54
| | | | | | | | | | | | | Exchange the old relocate mechanism with the new arch function call override mechanism that allows to create the ELF core header in the 2nd kernel. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Jan Willeke <willeke@de.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* s390/kprobes: add support for pc-relative long displacement instructionsHeiko Carstens2013-09-122-8/+140
| | | | | | | | | | | | | | | | | | | | | | | With the general-instruction extension facility (z10) a couple of instructions with a pc-relative long displacement were introduced. The kprobes support for these instructions however was never implemented. In result, if anybody ever put a probe on any of these instructions the result would have been random behaviour after the instruction got executed within the insn slot. So lets add the missing handling for these instructions. Since all of the new instructions have 32 bit signed displacement the easiest solution is to allocate an insn slot that is within the same 2GB area like the original instruction and patch the displacement field. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel-wide: fix missing validations on __get/__put/__copy_to/__copy_from_user()Mathieu Desnoyers2013-09-122-6/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I found the following pattern that leads in to interesting findings: grep -r "ret.*|=.*__put_user" * grep -r "ret.*|=.*__get_user" * grep -r "ret.*|=.*__copy" * The __put_user() calls in compat_ioctl.c, ptrace compat, signal compat, since those appear in compat code, we could probably expect the kernel addresses not to be reachable in the lower 32-bit range, so I think they might not be exploitable. For the "__get_user" cases, I don't think those are exploitable: the worse that can happen is that the kernel will copy kernel memory into in-kernel buffers, and will fail immediately afterward. The alpha csum_partial_copy_from_user() seems to be missing the access_ok() check entirely. The fix is inspired from x86. This could lead to information leak on alpha. I also noticed that many architectures map csum_partial_copy_from_user() to csum_partial_copy_generic(), but I wonder if the latter is performing the access checks on every architectures. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: make sure _PAGE_SWP_SOFT_DIRTY bit is not set on present pteCyrill Gorcunov2013-09-122-15/+22
| | | | | | | | | | | | | | _PAGE_SOFT_DIRTY bit should never be set on present pte so add VM_BUG_ON to catch any potential future abuse. Also add a comment on _PAGE_SWP_SOFT_DIRTY definition explaining scope of its usage. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Pavel Emelyanov <xemul@parallels.com> Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: migrate: check movability of hugepage in unmap_and_move_huge_page()Naoya Horiguchi2013-09-1211-0/+63
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently hugepage migration works well only for pmd-based hugepages (mainly due to lack of testing,) so we had better not enable migration of other levels of hugepages until we are ready for it. Some users of hugepage migration (mbind, move_pages, and migrate_pages) do page table walk and check pud/pmd_huge() there, so they are safe. But the other users (softoffline and memory hotremove) don't do this, so without this patch they can try to migrate unexpected types of hugepages. To prevent this, we introduce hugepage_migration_support() as an architecture dependent check of whether hugepage are implemented on a pmd basis or not. And on some architecture multiple sizes of hugepages are available, so hugepage_migration_support() also checks hugepage size. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: vmstats: track TLB flush stats on UP tooDave Hansen2013-09-123-9/+34
| | | | | | | | | | | | | | | | | | | | | | | | The previous patch doing vmstats for TLB flushes ("mm: vmstats: tlb flush counters") effectively missed UP since arch/x86/mm/tlb.c is only compiled for SMP. UP systems do not do remote TLB flushes, so compile those counters out on UP. arch/x86/kernel/cpu/mtrr/generic.c calls __flush_tlb() directly. This is probably an optimization since both the mtrr code and __flush_tlb() write cr4. It would probably be safe to make that a flush_tlb_all() (and then get these statistics), but the mtrr code is ancient and I'm hesitant to touch it other than to just stick in the counters. [akpm@linux-foundation.org: tweak comments] Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: vmstats: tlb flush countersDave Hansen2013-09-121-4/+14
| | | | | | | | | | | | | | | | | | | | I was investigating some TLB flush scaling issues and realized that we do not have any good methods for figuring out how many TLB flushes we are doing. It would be nice to be able to do these in generic code, but the arch-independent calls don't explicitly specify whether we actually need to do remote flushes or not. In the end, we really need to know if we actually _did_ global vs. local invalidations, so that leaves us with few options other than to muck with the counters from arch-specific code. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-09-1120-122/+117Star
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull more s390 updates from Heiko Carstens: "This includes one bpf/jit bug fix where the jit compiler could sometimes write generated code out of bounds of the allocated memory area. The rest of the patches are only cleanups and minor improvements" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/irq: reduce size of external interrupt handler hash array s390/compat,uid16: use current_cred() s390/ap_bus: use and-mask instead of a cast s390/ftrace: avoid pointer arithmetics with function pointers s390: make various functions static, add declarations to header files s390/compat signal: add couple of __force annotations s390/mm: add __releases()/__acquires() annotations to gmap_alloc_table() s390: keep Kconfig sorted s390/irq: rework irq subclass handling s390/irq: use hlists for external interrupt handler array s390/dumpstack: convert print_symbol to %pSR s390/perf: Remove print_hex_dump_bytes() debug output s390: update defconfig s390/bpf,jit: fix address randomization
| * s390/irq: reduce size of external interrupt handler hash arrayHeiko Carstens2013-09-091-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change the hash algorithm a bit so it produces only values in the range of 0..31. This allows to reduce the size of the external interrupt handler hash array even further while making sure that each of the known interrupt sources keeps its unique hash with the slightly modified algorithm: 0x1004 --> 12 0x1201 --> 10 0x1202 --> 11 0x1406 --> 16 0x1407 --> 17 0x2401 --> 19 0x2603 --> 22 0x4000 --> 0 This also means that the entire array now fits into exactly one cache line; so add a proper align statement as well. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390/compat,uid16: use current_cred()Heiko Carstens2013-09-071-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | 86a264ab "CRED: Wrap current->cred and a few other accessors" converted all uses of current->cred into current_cred() but left s390 alone. So let's convert s390 finally as well, only five years later. This way we also get rid of a sparse warning which complains about a possible invalid rcu dereference which however is a false positive. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390/ftrace: avoid pointer arithmetics with function pointersHeiko Carstens2013-09-071-2/+2
| | | | | | | | | | | | | | | | Pointer arithmetics with function pointers is not really defined, but seems to do the right thing. Let's cast to a void pointer to have a defined behaviour, at least when using gcc. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390: make various functions static, add declarations to header filesHeiko Carstens2013-09-078-16/+13Star
| | | | | | | | | | | | | | Make various functions static, add declarations to header files to fix a couple of sparse findings. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390/compat signal: add couple of __force annotationsHeiko Carstens2013-09-071-5/+5
| | | | | | | | | | | | | | | | | | Add __force annotations to get rid of a couple of sparse warnings: arch/s390/kernel/compat_signal.c:335:35: warning: cast removes address space of expression Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390/mm: add __releases()/__acquires() annotations to gmap_alloc_table()Heiko Carstens2013-09-071-1/+3
| | | | | | | | | | | | Let sparse not incorrectly complain about unbalanced locking. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390: keep Kconfig sortedHeiko Carstens2013-09-071-3/+3
| | | | | | | | Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390/irq: rework irq subclass handlingHeiko Carstens2013-09-046-51/+32Star
| | | | | | | | | | | | | | | | | | | | | | Let's not add a function for every external interrupt subclass for which we need reference counting. Just have two register/unregister functions which have a subclass parameter: void irq_subclass_register(enum irq_subclass subclass); void irq_subclass_unregister(enum irq_subclass subclass); Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390/irq: use hlists for external interrupt handler arrayHeiko Carstens2013-09-041-12/+12
| | | | | | | | | | | | | | Use hlists for the hashed array of external interrupt handlers. Reduces the size of the array by 50% (2KB). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390/dumpstack: convert print_symbol to %pSRHeiko Carstens2013-09-041-10/+10
| | | | | | | | | | | | | | | | This is the same as what other architectures did. The change has also the advantage that there won't be any interleaving messages between printk() and print_symbol(). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390/perf: Remove print_hex_dump_bytes() debug outputHendrik Brueckner2013-09-041-4/+1Star
| | | | | | | | | | Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390: update defconfigHeiko Carstens2013-09-041-12/+27
| | | | | | | | Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390/bpf,jit: fix address randomizationHeiko Carstens2013-09-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add misssing braces to hole calculation. This resulted in an addition instead of an substraction. Which in turn means that the jit compiler could try to write out of bounds of the allocated piece of memory. This bug was introduced with aa2d2c73 "s390/bpf,jit: address randomize and write protect jit code". Fixes this one: [ 37.320956] Unable to handle kernel pointer dereference at virtual kernel address 000003ff80231000 [ 37.320984] Oops: 0011 [#1] PREEMPT SMP DEBUG_PAGEALLOC [ 37.320993] Modules linked in: dm_multipath scsi_dh eadm_sch dm_mod ctcm fsm autofs4 [ 37.321007] CPU: 28 PID: 6443 Comm: multipathd Not tainted 3.10.9-61.x.20130829-s390xdefault #1 [ 37.321011] task: 0000004ada778000 ti: 0000004ae3304000 task.ti: 0000004ae3304000 [ 37.321014] Krnl PSW : 0704c00180000000 000000000012d1de (bpf_jit_compile+0x198e/0x23d0) [ 37.321022] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3 Krnl GPRS: 000000004350207d 0000004a00000001 0000000000000007 000003ff80231002 [ 37.321029] 0000000000000007 000003ff80230ffe 00000000a7740000 000003ff80230f76 [ 37.321032] 000003ffffffffff 000003ff00000000 000003ff0000007d 000000000071e820 [ 37.321035] 0000004adbe99950 000000000071ea18 0000004af3d9e7c0 0000004ae3307b80 [ 37.321046] Krnl Code: 000000000012d1d0: 41305004 la %r3,4(%r5) 000000000012d1d4: e330f0f80021 clg %r3,248(%r15) #000000000012d1da: a7240009 brc 2,12d1ec >000000000012d1de: 50805000 st %r8,0(%r5) 000000000012d1e2: e330f0f00004 lg %r3,240(%r15) 000000000012d1e8: 41303004 la %r3,4(%r3) 000000000012d1ec: e380f0e00004 lg %r8,224(%r15) 000000000012d1f2: e330f0f00024 stg %r3,240(%r15) [ 37.321074] Call Trace: [ 37.321077] ([<000000000012da78>] bpf_jit_compile+0x2228/0x23d0) [ 37.321083] [<00000000006007c2>] sk_attach_filter+0xfe/0x214 [ 37.321090] [<00000000005d2d92>] sock_setsockopt+0x926/0xbdc [ 37.321097] [<00000000005cbfb6>] SyS_setsockopt+0x8a/0xe8 [ 37.321101] [<00000000005ccaa8>] SyS_socketcall+0x264/0x364 [ 37.321106] [<0000000000713f1c>] sysc_nr_ok+0x22/0x28 [ 37.321113] [<000003fffce10ea8>] 0x3fffce10ea8 [ 37.321118] INFO: lockdep is turned off. [ 37.321121] Last Breaking-Event-Address: [ 37.321124] [<000000000012d192>] bpf_jit_compile+0x1942/0x23d0 [ 37.321132] [ 37.321135] Kernel panic - not syncing: Fatal exception: panic_on_oops Cc: stable@vger.kernel.org # v3.11 Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* | Merge branch 'merge' of ↵Linus Torvalds2013-09-114-14/+34
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Pull powerpc fixes from Ben Herrenschmidt: "Here are a handful of small powerpc fixes. A couple of section mismatches (always worth fixing), a missing export of a new symbol causing build failures of modules, a page fault deadlock fix (interestingly that bug has been around for a LONG time, though it seems to be more easily triggered by KVM) and fixing pseries default idle loop in the absence of the cpuidle drivers (such as during boot)" * 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: powerpc: Default arch idle could cede processor on pseries fbdev/ps3fb: Fix section mismatch warning for ps3fb_probe powerpc: Fix section mismatch warning for prom_rtas_call powerpc: Fix possible deadlock on page fault powerpc: Export cpu_to_chip_id() to fix build error
| * | powerpc: Default arch idle could cede processor on pseriesVaidyanathan Srinivasan2013-09-111-10/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When adding cpuidle support to pSeries, we introduced two regressions: - The new cpuidle backend driver only works under hypervisors supporting the "SLPLAR" option, which isn't the case of the old POWER4 hypervisor and the HV "light" used on js2x blades - The cpuidle driver registers fairly late, meaning that for a significant portion of the boot process, we end up having all threads spinning. This slows down the boot process and increases the overall resource usage if the hypervisor has shared processors. This fixes both by implementing a "default" idle that will cede to the hypervisor when possible, in a very simple way without all the bells and whisles of cpuidle. Reported-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> Acked-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: <stable@vger.kernel.org>
| * | powerpc: Fix section mismatch warning for prom_rtas_callVladimir Murzin2013-09-111-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While cross-building for PPC64 I've got WARNING: vmlinux.o(.text.unlikely+0x1ba): Section mismatch in reference from the function .prom_rtas_call() to the variable .init.data:dt_string_start The function .prom_rtas_call() references the variable __initdata dt_string_start. This is often because .prom_rtas_call lacks a __initdata annotation or the annotation of dt_string_start is wrong. WARNING: vmlinux.o(.meminit.text+0xeb0): Section mismatch in reference from the function .free_area_init_core.isra.47() to the function .init.text:.set_pageblock_order() The function __meminit .free_area_init_core.isra.47() references a function __init .set_pageblock_order(). If .set_pageblock_order is only used by .free_area_init_core.isra.47 then annotate .set_pageblock_order with a matching annotation. Fix it by proper annotation of prom_rtas_call. Signed-off-by: Vladimir Murzin <murzin.v@gmail.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | powerpc: Fix possible deadlock on page faultAneesh Kumar K.V2013-09-111-3/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | stack_grow_into/14082 is trying to acquire lock: (&mm->mmap_sem){++++++}, at: [<c000000000206d28>] .might_fault+0x78/0xe0 but task is already holding lock: (&mm->mmap_sem){++++++}, at: [<c0000000007ffd8c>] .do_page_fault+0x24c/0x910 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&mm->mmap_sem); lock(&mm->mmap_sem); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by stack_grow_into/14082: #0: (&mm->mmap_sem){++++++}, at: [<c0000000007ffd8c>] .do_page_fault+0x24c/0x910 stack backtrace: CPU: 21 PID: 14082 Comm: stack_grow_into Not tainted 3.10.0-10.el7.ppc64.debug #1 Call Trace: [c0000003d396b850] [c000000000016e7c] .show_stack+0x7c/0x1f0 (unreliable) [c0000003d396b920] [c000000000813fc8] .dump_stack+0x28/0x3c [c0000003d396b990] [c000000000124b90] .__lock_acquire+0x1640/0x1800 [c0000003d396bab0] [c00000000012570c] .lock_acquire+0xac/0x250 [c0000003d396bb80] [c000000000206d54] .might_fault+0xa4/0xe0 [c0000003d396bbf0] [c0000000007ffe2c] .do_page_fault+0x2ec/0x910 [c0000003d396be30] [c0000000000092e8] handle_page_fault+0x10/0x30 Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | powerpc: Export cpu_to_chip_id() to fix build errorGuenter Roeck2013-09-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | powerpc allmodconfig build fails with: ERROR: ".cpu_to_chip_id" [drivers/block/mtip32xx/mtip32xx.ko] undefined! The problem was introduced with commit 15863ff3b (powerpc: Make chip-id information available to userspace). Export the missing symbol. Cc: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> Cc: Shivaprasad G Bhat <sbhat@linux.vnet.ibm.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | | Merge tag 'stable/for-linus-3.12-rc0-tag-two' of ↵Linus Torvalds2013-09-115-48/+50
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen bug-fixes from Konrad Rzeszutek Wilk: "This pull I usually do after rc1 is out but because we have a nice amount of fixes, some bootup related fixes for ARM, and it is early in the cycle we figured to do it now to help with tracking of potential regressions. The simple ones are the ARM ones - one of the patches fell through the cracks, other fixes a bootup issue (unconditionally using Xen functions). Then a fix for a regression causing preempt count being off (patch causing this went in v3.12). Lastly are the fixes to make Xen PVHVM guests use PV ticketlocks (Xen PV already does). The enablement of that was supposed to be part of the x86 spinlock merge in commit 816434ec4a67 ("The biggest change here are paravirtualized ticket spinlocks (PV spinlocks), which bring a nice speedup on various benchmarks...") but unfortunatly it would cause hang when booting Xen PVHVM guests. Yours truly got all of the bugs fixed last week and they (six of them) are included in this pull. Bug-fixes: - Boot on ARM without using Xen unconditionally - On Xen ARM don't run cpuidle/cpufreq - Fix regression in balloon driver, preempt count warnings - Fixes to make PVHVM able to use pv ticketlock. - Revert Xen PVHVM disabling pv ticketlock (aka, re-enable pv ticketlocks)" * tag 'stable/for-linus-3.12-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/spinlock: Don't use __initdate for xen_pv_spin Revert "xen/spinlock: Disable IRQ spinlock (PV) allocation on PVHVM" xen/spinlock: Don't setup xen spinlock IPI kicker if disabled. xen/smp: Update pv_lock_ops functions before alternative code starts under PVHVM xen/spinlock: We don't need the old structure anymore xen/spinlock: Fix locking path engaging too soon under PVHVM. xen/arm: disable cpuidle and cpufreq when linux is running as dom0 xen/p2m: Don't call get_balloon_scratch_page() twice, keep interrupts disabled for multicalls ARM: xen: only set pm function ptrs for Xen guests
| * | | xen/spinlock: Don't use __initdate for xen_pv_spinKonrad Rzeszutek Wilk2013-09-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As we get compile warnings about .init.data being used by non-init functions. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | Revert "xen/spinlock: Disable IRQ spinlock (PV) allocation on PVHVM"Konrad Rzeszutek Wilk2013-09-091-20/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 70dd4998cb85f0ecd6ac892cc7232abefa432efb. Now that the bugs have been resolved we can re-enable the PV ticketlock implementation under PVHVM Xen guests. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
| * | | xen/spinlock: Don't setup xen spinlock IPI kicker if disabled.Konrad Rzeszutek Wilk2013-09-091-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no need to setup this kicker IPI if we are never going to use the paravirtualized ticketlock mechanism. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
| * | | xen/smp: Update pv_lock_ops functions before alternative code starts under PVHVMKonrad Rzeszutek Wilk2013-09-091-5/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before this patch we would patch all of the pv_lock_ops sites using alternative assembler. Then later in the bootup cycle change the unlock_kick and lock_spinning to the Xen specific - without re patching. That meant that for the core of the kernel we would be running with the baremetal version of unlock_kick and lock_spinning while for modules we would have the proper Xen specific slowpaths. As most of the module uses some API from the core kernel that ended up with slowpath lockers waiting forever to be kicked (b/c they would be using the Xen specific slowpath logic). And the kick never came b/c the unlock path that was taken was the baremetal one. On PV we do not have the problem as we initialise before the alternative code kicks in. The fix is to make the updating of the pv_lock_ops function be done before the alternative code starts patching. Note that this patch fixes issues discovered by commit f10cd522c5fbfec9ae3cc01967868c9c2401ed23. ("xen: disable PV spinlocks on HVM") wherein it mentioned PV spinlocks cannot possibly work with the current code because they are enabled after pvops patching has already been done, and because PV spinlocks use a different data structure than native spinlocks so we cannot switch between them dynamically. The first problem is solved by this patch. The second problem has been solved by commit 816434ec4a674fcdb3c2221a6dffdc8f34020550 (Merge branch 'x86-spinlocks-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip) P.S. There is still the commit 70dd4998cb85f0ecd6ac892cc7232abefa432efb (xen/spinlock: Disable IRQ spinlock (PV) allocation on PVHVM) to revert but that can be done later after all other bugs have been fixed. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
| * | | xen/spinlock: We don't need the old structure anymoreKonrad Rzeszutek Wilk2013-09-091-18/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As we are using the generic ticketlock structs and these old structures are not needed anymore. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
| * | | xen/spinlock: Fix locking path engaging too soon under PVHVM.Konrad Rzeszutek Wilk2013-09-092-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The xen_lock_spinning has a check for the kicker interrupts and if it is not initialized it will spin normally (not enter the slowpath). But for PVHVM case we would initialize the kicker interrupt before the CPU came online. This meant that if the booting CPU used a spinlock and went in the slowpath - it would enter the slowpath and block forever. The forever part because during bootup: the spinlock would be taken _before_ the CPU sets itself to be online (more on this further), and we enter to poll on the event channel forever. The bootup CPU (see commit fc78d343fa74514f6fd117b5ef4cd27e4ac30236 "xen/smp: initialize IPI vectors before marking CPU online" for details) and the CPU that started the bootup consult the cpu_online_mask to determine whether the booting CPU should get an IPI. The booting CPU has to set itself in this mask via: set_cpu_online(smp_processor_id(), true); However, if the spinlock is taken before this (and it is) and it polls on an event channel - it will never be woken up as the kernel will never send an IPI to an offline CPU. Note that the PVHVM logic in sending IPIs is using the HVM path which has numerous checks using the cpu_online_mask and cpu_active_mask. See above mention git commit for details. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
| * | | Merge tag 'v3.11-rc7' into stable/for-linus-3.12Konrad Rzeszutek Wilk2013-09-09118-411/+847
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Linux 3.11-rc7 As we need the git commit 28817e9de4f039a1a8c1fe1df2fa2df524626b9e Author: Chuck Anderson <chuck.anderson@oracle.com> Date: Tue Aug 6 15:12:19 2013 -0700 xen/smp: initialize IPI vectors before marking CPU online * tag 'v3.11-rc7': (443 commits) Linux 3.11-rc7 ARC: [lib] strchr breakage in Big-endian configuration VFS: collect_mounts() should return an ERR_PTR bfs: iget_locked() doesn't return an ERR_PTR efs: iget_locked() doesn't return an ERR_PTR() proc: kill the extra proc_readfd_common()->dir_emit_dots() cope with potentially long ->d_dname() output for shmem/hugetlb usb: phy: fix build breakage USB: OHCI: add missing PCI PM callbacks to ohci-pci.c staging: comedi: bug-fix NULL pointer dereference on failed attach lib/lz4: correct the LZ4 license memcg: get rid of swapaccount leftovers nilfs2: fix issue with counting number of bio requests for BIO_EOPNOTSUPP error detection nilfs2: remove double bio_put() in nilfs_end_bio_write() for BIO_EOPNOTSUPP error drivers/platform/olpc/olpc-ec.c: initialise earlier ipv4: expose IPV4_DEVCONF ipv6: handle Redirect ICMP Message with no Redirected Header option be2net: fix disabling TX in be_close() Revert "ACPI / video: Always call acpi_video_init_brightness() on init" Revert "genetlink: fix family dump race" ... Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * \ \ \ Merge branch 'x86/spinlocks' of ↵Konrad Rzeszutek Wilk2013-09-0911-353/+531
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into stable/for-linus-3.12 * 'x86/spinlocks' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/kvm/guest: Fix sparse warning: "symbol 'klock_waiting' was not declared as static" kvm: Paravirtual ticketlocks support for linux guests running on KVM hypervisor kvm guest: Add configuration support to enable debug information for KVM Guests kvm uapi: Add KICK_CPU and PV_UNHALT definition to uapi xen, pvticketlock: Allow interrupts to be enabled while blocking x86, ticketlock: Add slowpath logic jump_label: Split jumplabel ratelimit x86, pvticketlock: When paravirtualizing ticket locks, increment by 2 x86, pvticketlock: Use callee-save for lock_spinning xen, pvticketlocks: Add xen_nopvspin parameter to disable xen pv ticketlocks xen, pvticketlock: Xen implementation for PV ticket locks xen: Defer spinlock setup until boot CPU setup x86, ticketlock: Collapse a layer of functions x86, ticketlock: Don't inline _spin_unlock when using paravirt spinlocks x86, spinlock: Replace pv spinlocks with pv ticketlocks
| * | | | | xen/arm: disable cpuidle and cpufreq when linux is running as dom0Julien Grall2013-09-091-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When linux is running as dom0, Xen doesn't show the physical cpu but a virtual CPU. On some ARM SOC (for instance the exynos 5250), linux registers callbacks for cpuidle and cpufreq. When these callbacks are called, they will modify directly the physical cpu not the virtual one. It can impact the whole board instead of only dom0. Signed-off-by: Julien Grall <julien.grall@linaro.org> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | xen/p2m: Don't call get_balloon_scratch_page() twice, keep interrupts ↵Boris Ostrovsky2013-09-091-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | disabled for multicalls m2p_remove_override() calls get_balloon_scratch_page() in MULTI_update_va_mapping() even though it already has pointer to this page from the earlier call (in scratch_page). This second call doesn't have a matching put_balloon_scratch_page() thus not restoring preempt count back. (Also, there is no put_balloon_scratch_page() in the error path.) In addition, the second multicall uses __xen_mc_entry() which does not disable interrupts. Rearrange xen_mc_* calls to keep interrupts off while performing multicalls. This commit fixes a regression introduced by: commit ee0726407feaf504dff304fb603652fb2d778b42 Author: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Date: Tue Jul 23 17:23:54 2013 +0000 xen/m2p: use GNTTABOP_unmap_and_replace to reinstate the original mapping Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
| * | | | | ARM: xen: only set pm function ptrs for Xen guestsRob Herring2013-09-091-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xen_pm_init was unconditionally setting pm_power_off and arm_pm_restart function pointers. This breaks multi-platform kernels. Make this conditional on running as a Xen guest and make it a late_initcall to ensure it is setup after platform code for Dom0. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> CC: stable@vger.kernel.org
* | | | | | Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linuxLinus Torvalds2013-09-111-0/+154
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull drm fixes from Dave Airlie: "Daniel had some fixes queued up, that were delayed, the stolen memory ones and vga arbiter ones are quite useful, along with his usual bunch of stuff, nothing for HSW outputs yet. The one nouveau fix is for a regression I caused with the poweroff stuff" * 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (30 commits) drm/nouveau: fix oops on runtime suspend/resume drm/i915: Delay disabling of VGA memory until vgacon->fbcon handoff is done drm/i915: try not to lose backlight CBLV precision drm/i915: Confine page flips to BCS on Valleyview drm/i915: Skip stolen region initialisation if none is reserved drm/i915: fix gpu hang vs. flip stall deadlocks drm/i915: Hold an object reference whilst we shrink it drm/i915: fix i9xx_crtc_clock_get for multiplied pixels drm/i915: handle sdvo input pixel multiplier correctly again drm/i915: fix hpd work vs. flush_work in the pageflip code deadlock drm/i915: fix up the relocate_entry refactoring drm/i915: Fix pipe config warnings when dealing with LVDS fixed mode drm/i915: Don't call sg_free_table() if sg_alloc_table() fails i915: Update VGA arbiter support for newer devices vgaarb: Fix VGA decodes changes vgaarb: Don't disable resources that are not owned drm/i915: Pin pages whilst mapping the dma-buf drm/i915: enable trickle feed on Haswell x86: add early quirk for reserving Intel graphics stolen memory v5 drm/i915: split PCI IDs out into i915_drm.h v4 ...
| * | | | | | x86: add early quirk for reserving Intel graphics stolen memory v5Jesse Barnes2013-09-031-0/+154
| | |_|/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Systems with Intel graphics controllers set aside memory exclusively for gfx driver use. This memory is not always marked in the E820 as reserved or as RAM, and so is subject to overlap from E820 manipulation later in the boot process. On some systems, MMIO space is allocated on top, despite the efforts of the "RAM buffer" approach, which simply rounds memory boundaries up to 64M to try to catch space that may decode as RAM and so is not suitable for MMIO. v2: use read_pci_config for 32 bit reads instead of adding a new one (Chris) add gen6 stolen size function (Chris) v3: use a function pointer (Chris) drop gen2 bits (Daniel) v4: call e820_sanitize_map after adding the region v5: fixup comments (Peter) simplify loop (Chris) Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Acked-by: H. Peter Anvin <hpa@zytor.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66726 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66844 Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* | | | | | Merge branch 'x86/jumplabel' of ↵Linus Torvalds2013-09-112-6/+73
|\ \ \ \ \ \ | |_|_|_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 jumplabel changes from Peter Anvin: "One more x86 tree for this merge window. This tree improves the handling of jump labels, so that most of the time we don't have to do a massive initial patching run. Furthermore, we will error out of the jump label is not what is expected, eg if it has been corrupted or tampered with" * 'x86/jumplabel' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/jump-label: Show where and what was wrong on errors x86/jump-label: Add safety checks to jump label conversions x86/jump-label: Do not bother updating nops if they are correct x86/jump-label: Use best default nops for inital jump label calls
| * | | | | x86/jump-label: Show where and what was wrong on errorsSteven Rostedt2013-08-071-3/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When modifying text sections for jump labels, a paranoid check is performed. If the check fails, the system "bugs". But why it failed is not shown. The BUG_ON()s in the jump label update code is replaced with bug_at(ip). This is a function that will show what pointer failed, and what was at the location of the failure that made jump label panic. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | x86/jump-label: Add safety checks to jump label conversionsSteven Rostedt2013-08-071-4/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As with all modifying of kernel text, we need to be very paranoid. When converting the jump label locations to and from nops to jumps a check has been added to make sure what we are replacing is what we expect, otherwise we bug. Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jason Baron <jbaron@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | x86/jump-label: Do not bother updating nops if they are correctSteven Rostedt2013-08-071-1/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On boot up, the jump label init function scans all the jump label locations and converts them to the best nop for the machine. If the nop is already the ideal nop, do not bother with changing it. Cc: Jason Baron <jbaron@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | x86/jump-label: Use best default nops for inital jump label callsSteven Rostedt2013-08-071-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As specified by H. Peter Anvin, the best nops for x86 without knowing the running computer is: 32bit: 0x3e, 0x8d, 0x74, 0x26, 0x00 also known as GENERIC_NOP5_ATOMIC 64bit: 0x0f, 0x1f, 0x44, 0x00, 0x00 also known as P6_NOP5_ATOMIC Currently the default nop that is used by jump label is: 0xe9 0x00 0x00 0x00 0x00 Which is really a 5byte jump to the next position. It's better to use a real nop than a jmp. Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Jason Baron <jbaron@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-07-20 22:56:32 +0200