summaryrefslogtreecommitdiffstats
Commit message (Collapse)AuthorAgeFilesLines
* sched/core: Stop setting PREEMPT_ACTIVEPeter Zijlstra2015-10-062-25/+6Star
| | | | | | | | | | | | | | Now that nothing tests for PREEMPT_ACTIVE anymore, stop setting it. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/core: Fix trace_sched_switch()Peter Zijlstra2015-10-065-17/+14Star
| | | | | | | | | | | | | | | __trace_sched_switch_state() is the last remaining PREEMPT_ACTIVE user, move trace_sched_switch() from prepare_task_switch() to __schedule() and propagate the @preempt argument. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/core: Add preempt argument to __schedule()Peter Zijlstra2015-10-061-6/+6
| | | | | | | | | | | | | | | | | There is only a single PREEMPT_ACTIVE use in the regular __schedule() path and that is to circumvent the task->state check. Since the code setting PREEMPT_ACTIVE is the immediate caller of __schedule() we can replace this with a function argument. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/core: Create preempt_count invariantPeter Zijlstra2015-10-064-9/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | Assuming units of PREEMPT_DISABLE_OFFSET for preempt_count() numbers. Now that TASK_DEAD no longer results in preempt_count() == 3 during scheduling, we will always call context_switch() with preempt_count() == 2. However, we don't always end up with preempt_count() == 2 in finish_task_switch() because new tasks get created with preempt_count() == 1. Create FORK_PREEMPT_COUNT and set it to 2 and use that in the right places. Note that we cannot use INIT_PREEMPT_COUNT as that serves another purpose (boot). After this, preempt_count() is invariant across the context switch, with exception of PREEMPT_ACTIVE. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: 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>
* sched/core: Rework TASK_DEAD preemption exceptionPeter Zijlstra2015-10-061-6/+13
| | | | | | | | | | | | | | | | | | | | | TASK_DEAD is special in that the final schedule call from do_exit() must be done with preemption disabled. This means we end up scheduling with a preempt_count() higher than usual (3 instead of the 'expected' 2). Since future patches will want to rely on an invariant preempt_count() value during schedule, fix this up. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/core: Simplify INIT_PREEMPT_COUNTPeter Zijlstra2015-10-061-6/+5Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | As per the following commit: d86ee4809d03 ("sched: optimize cond_resched()") we need PREEMPT_ACTIVE to avoid cond_resched() from working before the scheduler is set up. However, keeping preemption disabled should do the same thing already, making the PREEMPT_ACTIVE part entirely redundant. The only complication is !PREEMPT_COUNT kernels, where PREEMPT_DISABLED ends up being 0. Instead we use an unconditional PREEMPT_OFFSET to set preempt_count() even on !PREEMPT_COUNT kernels. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'sched/urgent' into sched/core, to pick up fixes before ↵Ingo Molnar2015-10-061019-5198/+8736
|\ | | | | | | | | | | applying new changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * sched/core: Fix TASK_DEAD race in finish_task_switch()Peter Zijlstra2015-10-062-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So the problem this patch is trying to address is as follows: CPU0 CPU1 context_switch(A, B) ttwu(A) LOCK A->pi_lock A->on_cpu == 0 finish_task_switch(A) prev_state = A->state <-. WMB | A->on_cpu = 0; | UNLOCK rq0->lock | | context_switch(C, A) `-- A->state = TASK_DEAD prev_state == TASK_DEAD put_task_struct(A) context_switch(A, C) finish_task_switch(A) A->state == TASK_DEAD put_task_struct(A) The argument being that the WMB will allow the load of A->state on CPU0 to cross over and observe CPU1's store of A->state, which will then result in a double-drop and use-after-free. Now the comment states (and this was true once upon a long time ago) that we need to observe A->state while holding rq->lock because that will order us against the wakeup; however the wakeup will not in fact acquire (that) rq->lock; it takes A->pi_lock these days. We can obviously fix this by upgrading the WMB to an MB, but that is expensive, so we'd rather avoid that. The alternative this patch takes is: smp_store_release(&A->on_cpu, 0), which avoids the MB on some archs, but not important ones like ARM. Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@vger.kernel.org> # v3.1+ Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Cc: manfred@colorfullife.com Cc: will.deacon@arm.com Fixes: e4a52bcb9a18 ("sched: Remove rq->lock from the first half of ttwu()") Link: http://lkml.kernel.org/r/20150929124509.GG3816@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * Linux 4.3-rc4Linus Torvalds2015-10-041-1/+1
| |
| * Merge branch 'strscpy' of ↵Linus Torvalds2015-10-0425-37/+188
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile Pull strscpy string copy function implementation from Chris Metcalf. Chris sent this during the merge window, but I waffled back and forth on the pull request, which is why it's going in only now. The new "strscpy()" function is definitely easier to use and more secure than either strncpy() or strlcpy(), both of which are horrible nasty interfaces that have serious and irredeemable problems. strncpy() has a useless return value, and doesn't NUL-terminate an overlong result. To make matters worse, it pads a short result with zeroes, which is a performance disaster if you have big buffers. strlcpy(), by contrast, is a mis-designed "fix" for strlcpy(), lacking the insane NUL padding, but having a differently broken return value which returns the original length of the source string. Which means that it will read characters past the count from the source buffer, and you have to trust the source to be properly terminated. It also makes error handling fragile, since the test for overflow is unnecessarily subtle. strscpy() avoids both these problems, guaranteeing the NUL termination (but not excessive padding) if the destination size wasn't zero, and making the overflow condition very obvious by returning -E2BIG. It also doesn't read past the size of the source, and can thus be used for untrusted source data too. So why did I waffle about this for so long? Every time we introduce a new-and-improved interface, people start doing these interminable series of trivial conversion patches. And every time that happens, somebody does some silly mistake, and the conversion patch to the improved interface actually makes things worse. Because the patch is mindnumbing and trivial, nobody has the attention span to look at it carefully, and it's usually done over large swatches of source code which means that not every conversion gets tested. So I'm pulling the strscpy() support because it *is* a better interface. But I will refuse to pull mindless conversion patches. Use this in places where it makes sense, but don't do trivial patches to fix things that aren't actually known to be broken. * 'strscpy' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: tile: use global strscpy() rather than private copy string: provide strscpy() Make asm/word-at-a-time.h available on all architectures
| | * tile: use global strscpy() rather than private copyChris Metcalf2015-09-101-29/+4Star
| | | | | | | | | | | | | | | | | | Now that strscpy() is a standard API, remove the local copy. Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
| | * string: provide strscpy()Chris Metcalf2015-09-102-0/+91
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The strscpy() API is intended to be used instead of strlcpy(), and instead of most uses of strncpy(). - Unlike strlcpy(), it doesn't read from memory beyond (src + size). - Unlike strlcpy() or strncpy(), the API provides an easy way to check for destination buffer overflow: an -E2BIG error return value. - The provided implementation is robust in the face of the source buffer being asynchronously changed during the copy, unlike the current implementation of strlcpy(). - Unlike strncpy(), the destination buffer will be NUL-terminated if the string in the source buffer is too long. - Also unlike strncpy(), the destination buffer will not be updated beyond the NUL termination, avoiding strncpy's behavior of zeroing the entire tail end of the destination buffer. (A memset() after the strscpy() can be used if this behavior is desired.) - The implementation should be reasonably performant on all platforms since it uses the asm/word-at-a-time.h API rather than simple byte copy. Kernel-to-kernel string copy is not considered to be performance critical in any case. Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
| | * Make asm/word-at-a-time.h available on all architecturesChris Metcalf2015-07-0822-8/+93
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Added the x86 implementation of word-at-a-time to the generic version, which previously only supported big-endian. Omitted the x86-specific load_unaligned_zeropad(), which in any case is also not present for the existing BE-only implementation of a word-at-a-time, and is only used under CONFIG_DCACHE_WORD_ACCESS. Added as a "generic-y" to the Kbuilds of all architectures that didn't previously have it. Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
| * | Merge tag 'md/4.3-fixes' of git://neil.brown.name/mdLinus Torvalds2015-10-047-26/+28
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull md fixes from Neil Brown: "Assorted fixes for md in 4.3-rc. Two tagged for -stable, and one is really a cleanup to match and improve kmemcache interface. * tag 'md/4.3-fixes' of git://neil.brown.name/md: md/bitmap: don't pass -1 to bitmap_storage_alloc. md/raid1: Avoid raid1 resync getting stuck md: drop null test before destroy functions md: clear CHANGE_PENDING in readonly array md/raid0: apply base queue limits *before* disk_stack_limits md/raid5: don't index beyond end of array in need_this_block(). raid5: update analysis state for failed stripe md: wait for pending superblock updates before switching to read-only
| | * | md/bitmap: don't pass -1 to bitmap_storage_alloc.NeilBrown2015-10-021-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Passing -1 to bitmap_storage_alloc() causes page->index to be set to -1, which is quite problematic. So only pass ->cluster_slot if mddev_is_clustered(). Fixes: b97e92574c0b ("Use separate bitmaps for each nodes in the cluster") Cc: stable@vger.kernel.org (v4.1+) Signed-off-by: NeilBrown <neilb@suse.com>
| | * | md/raid1: Avoid raid1 resync getting stuckJes Sorensen2015-10-021-3/+2Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | close_sync() needs to set conf->next_resync to a large, but safe value below MaxSector and use it to determine whether or not to set start_next_window in wait_barrier() Solution suggested by Neil Brown. Reported-by: Nate Dailey <nate.dailey@stratus.com> Tested-by: Xiao Ni <xni@redhat.com> Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com> Signed-off-by: NeilBrown <neilb@suse.com>
| | * | md: drop null test before destroy functionsJulia Lawall2015-10-024-14/+7Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove unneeded NULL test. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression x; @@ -if (x != NULL) \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: NeilBrown <neilb@suse.com>
| | * | md: clear CHANGE_PENDING in readonly arrayShaohua Li2015-10-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If faulty disks of an array are more than allowed degraded number, the array enters error handling. It will be marked as read-only with MD_CHANGE_PENDING/RECOVERY_NEEDED set. But currently recovery doesn't clear CHANGE_PENDING bit for read-only array. If MD_CHANGE_PENDING is set for a raid5 array, all returned IO will be hold on a list till the bit is clear. But recovery nevery clears this bit, the IO is always in pending state and nevery finish. This has bad effects like upper layer can't get an IO error and the array can't be stopped. Fixes: c3cce6cda162 ("md/raid5: ensure device failure recorded before write request returns.") Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
| | * | md/raid0: apply base queue limits *before* disk_stack_limitsNeilBrown2015-10-021-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Calling e.g. blk_queue_max_hw_sectors() after calls to disk_stack_limits() discards the settings determined by disk_stack_limits(). So we need to make those calls first. Fixes: 199dc6ed5179 ("md/raid0: update queue parameter in a safer location.") Cc: stable@vger.kernel.org (v2.6.35+ - please apply with 199dc6ed5179). Reported-by: Jes Sorensen <Jes.Sorensen@redhat.com> Signed-off-by: NeilBrown <neilb@suse.com>
| | * | md/raid5: don't index beyond end of array in need_this_block().NeilBrown2015-10-021-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When need_this_block probably shouldn't be called when there are more than 2 failed devices, we really don't want it to try indexing beyond the end of the failed_num[] of fdev[] arrays. So limit the loops to at most 2 iterations. Reported-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.de>
| | * | raid5: update analysis state for failed stripeShaohua Li2015-10-021-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | handle_failed_stripe() makes the stripe fail, eg, all IO will return with a failure, but it doesn't update stripe_head_state. Later handle_stripe() has special handling for raid6 for handle_stripe_fill(). That check before handle_stripe_fill() doesn't skip the failed stripe and we get a kernel crash in need_this_block. This patch clear the analysis state to make sure no functions wrongly called after handle_failed_stripe() Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
| | * | md: wait for pending superblock updates before switching to read-onlyNeilBrown2015-10-021-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a superblock update is pending, wait for it to complete before letting md_set_readonly() switch to readonly. Otherwise we might lose important information about a device having failed. For external arrays, waiting for superblock updates can wait on user-space, so in that case, just return an error. Reported-and-tested-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
| * | | Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds2015-10-0413-144/+82Star
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull MIPS updates from Ralf Baechle: "This week's round of MIPS fixes: - Fix JZ4740 build - Fix fallback to GFP_DMA - FP seccomp in case of ENOSYS - Fix bootmem panic - A number of FP and CPS fixes - Wire up new syscalls - Make sure BPF assembler objects can properly be disassembled - Fix BPF assembler code for MIPS I" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: MIPS: scall: Always run the seccomp syscall filters MIPS: Octeon: Fix kernel panic on startup from memory corruption MIPS: Fix R2300 FP context switch handling MIPS: Fix octeon FP context switch handling MIPS: BPF: Fix load delay slots. MIPS: BPF: Do all exports of symbols with FEXPORT(). MIPS: Fix the build on jz4740 after removing the custom gpio.h MIPS: CPS: #ifdef on CONFIG_MIPS_MT_SMP rather than CONFIG_MIPS_MT MIPS: CPS: Don't include MT code in non-MT kernels. MIPS: CPS: Stop dangling delay slot from has_mt. MIPS: dma-default: Fix 32-bit fall back to GFP_DMA MIPS: Wire up userfaultfd and membarrier syscalls.
| | * | | MIPS: scall: Always run the seccomp syscall filtersMarkos Chandras2015-10-044-73/+42Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The MIPS syscall handler code used to return -ENOSYS on invalid syscalls. Whilst this is expected, it caused problems for seccomp filters because the said filters never had the change to run since the code returned -ENOSYS before triggering them. This caused problems on the chromium testsuite for filters looking for invalid syscalls. This has now changed and the seccomp filters are always run even if the syscall is invalid. We return -ENOSYS once we return from the seccomp filters. Moreover, similar codepaths have been merged in the process which simplifies somewhat the overall syscall code. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/11236/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * | | MIPS: Octeon: Fix kernel panic on startup from memory corruptionMatt Bennett2015-10-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During development it was found that a number of builds would panic during the kernel init process, more specifically in 'delayed_fput()'. The panic showed the kernel trying to access a memory address of '0xb7fdc00' while traversing the 'delayed_fput_list' structure. Comparing this memory address to the value of the pointer used on builds that did not panic confirmed that the pointer on crashing builds must have been corrupted at some stage earlier in the init process. By traversing the list earlier and earlier in the code it was found that 'plat_mem_setup()' was responsible for corrupting the list. Specifically the line: memory = cvmx_bootmem_phy_alloc(mem_alloc_size, __pa_symbol(&__init_end), -1, 0x100000, CVMX_BOOTMEM_FLAG_NO_LOCKING); Which would eventually call: cvmx_bootmem_phy_set_size(new_ent_addr, cvmx_bootmem_phy_get_size (ent_addr) - (desired_min_addr - ent_addr)); Where 'new_ent_addr'=0x4800000 (the address of 'delayed_fput_list') and the second argument (size)=0xb7fdc00 (the address causing the kernel panic). The job of this part of 'plat_mem_setup()' is to allocate chunks of memory for the kernel to use. At the start of each chunk of memory the size of the chunk is written, hence the value 0xb7fdc00 is written onto memory at 0x4800000, therefore the kernel panics when it goes back to access 'delayed_fput_list' later on in the initialisation process. On builds that were not crashing it was found that the compiler had placed 'delayed_fput_list' at 0x4800008, meaning it wasn't corrupted (but something else in memory was overwritten). As can be seen in the first function call above the code begins to allocate chunks of memory beginning from the symbol '__init_end'. The MIPS linker script (vmlinux.lds.S) however defines the .bss section to begin after '__init_end'. Therefore memory within the .bss section is allocated to the kernel to use (System.map shows 'delayed_fput_list' and other kernel structures to be in .bss). To stop the kernel panic (and the .bss section being corrupted) memory should begin being allocated from the symbol '_end'. Signed-off-by: Matt Bennett <matt.bennett@alliedtelesis.co.nz> Acked-by: David Daney <david.daney@cavium.com> Cc: linux-mips@linux-mips.org Cc: aleksey.makarov@auriga.com Patchwork: https://patchwork.linux-mips.org/patch/11251/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * | | MIPS: Fix R2300 FP context switch handlingPaul Burton2015-10-021-27/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 1a3d59579b9f ("MIPS: Tidy up FPU context switching") removed FP context saving from the asm-written resume function in favour of reusing existing code to perform the same task. However it only removed the FP context saving code from the r4k_switch.S implementation of resume. Remove it from the r2300_switch.S implementation too in order to prevent attempting to save the FP context twice, which would likely lead to an exception from the second save because the FPU had already been disabled by the first save. This patch has only been build tested, using rbtx49xx_defconfig. Fixes: 1a3d59579b9f ("MIPS: Tidy up FPU context switching") Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-kernel@vger.kernel.org Cc: Manuel Lauss <manuel.lauss@gmail.com> Patchwork: https://patchwork.linux-mips.org/patch/11167/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * | | MIPS: Fix octeon FP context switch handlingPaul Burton2015-10-021-25/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 1a3d59579b9f ("MIPS: Tidy up FPU context switching") removed FP context saving from the asm-written resume function in favour of reusing existing code to perform the same task. However it only removed the FP context saving code from the r4k_switch.S implementation of resume. Octeon uses its own implementation in octeon_switch.S, so remove FP context saving there too in order to prevent attempting to save context twice. That formerly led to an exception from the second save as follows because the FPU had already been disabled by the first save: do_cpu invoked from kernel context![#1]: CPU: 0 PID: 2 Comm: kthreadd Not tainted 4.3.0-rc2-dirty #2 task: 800000041f84a008 ti: 800000041f864000 task.ti: 800000041f864000 $ 0 : 0000000000000000 0000000010008ce1 0000000000100000 ffffffffbfffffff $ 4 : 800000041f84a008 800000041f84ac08 800000041f84c000 0000000000000004 $ 8 : 0000000000000001 0000000000000000 0000000000000000 0000000000000001 $12 : 0000000010008ce3 0000000000119c60 0000000000000036 800000041f864000 $16 : 800000041f84ac08 800000000792ce80 800000041f84a008 ffffffff81758b00 $20 : 0000000000000000 ffffffff8175ae50 0000000000000000 ffffffff8176c740 $24 : 0000000000000006 ffffffff81170300 $28 : 800000041f864000 800000041f867d90 0000000000000000 ffffffff815f3fa0 Hi : 0000000000fa8257 Lo : ffffffffe15cfc00 epc : ffffffff8112821c resume+0x9c/0x200 ra : ffffffff815f3fa0 __schedule+0x3f0/0x7d8 Status: 10008ce2 KX SX UX KERNEL EXL Cause : 1080002c (ExcCode 0b) PrId : 000d0601 (Cavium Octeon+) Modules linked in: Process kthreadd (pid: 2, threadinfo=800000041f864000, task=800000041f84a008, tls=0000000000000000) Stack : ffffffff81604218 ffffffff815f7e08 800000041f84a008 ffffffff811681b0 800000041f84a008 ffffffff817e9878 0000000000000000 ffffffff81770000 ffffffff81768340 ffffffff81161398 0000000000000001 0000000000000000 0000000000000000 ffffffff815f4424 0000000000000000 ffffffff81161d68 ffffffff81161be8 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 ffffffff8111e16c 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 ... Call Trace: [<ffffffff8112821c>] resume+0x9c/0x200 [<ffffffff815f3fa0>] __schedule+0x3f0/0x7d8 [<ffffffff815f4424>] schedule+0x34/0x98 [<ffffffff81161d68>] kthreadd+0x180/0x198 [<ffffffff8111e16c>] ret_from_kernel_thread+0x14/0x1c Tested using cavium_octeon_defconfig on an EdgeRouter Lite. Fixes: 1a3d59579b9f ("MIPS: Tidy up FPU context switching") Reported-by: Aaro Koskinen <aaro.koskinen@nokia.com> Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Aleksey Makarov <aleksey.makarov@auriga.com> Cc: linux-kernel@vger.kernel.org Cc: Chandrakala Chavva <cchavva@caviumnetworks.com> Cc: David Daney <david.daney@cavium.com> Cc: Leonid Rosenboim <lrosenboim@caviumnetworks.com> Patchwork: https://patchwork.linux-mips.org/patch/11166/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * | | MIPS: BPF: Fix load delay slots.Ralf Baechle2015-10-021-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The entire bpf_jit_asm.S is written in noreorder mode because "we know better" according to a comment. This also prevented the assembler from throwing in the required NOPs for MIPS I processors which have no load-use interlock, thus the load's consumer might end up using the old value of the register from prior to the load. Fixed by putting the assembler in reorder mode for just the affected load instructions. This is not enough for gas to actually try to be clever by looking at the next instruction and inserting a nop only when needed but as the comment said "we know better", so getting gas to unconditionally emit a NOP is just right in this case and prevents adding further ifdefery. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * | | MIPS: BPF: Do all exports of symbols with FEXPORT().Ralf Baechle2015-10-011-6/+3Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | FEXPORT also marks the symbol as code using .type symbol, @function. Without objdump -d will output only a hexdump for code following the affected symbols. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * | | MIPS: Fix the build on jz4740 after removing the custom gpio.hAlban Bedel2015-10-012-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Somehow the wrong version of the patch to remove the use of custom gpio.h on mips has been merged. This patch add the missing fixes for a build error on jz4740 because linux/gpio.h doesn't provide any machine specfics definitions anymore. Signed-off-by: Alban Bedel <albeu@free.fr> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Brian Norris <computersforpeace@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/11089/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * | | MIPS: CPS: #ifdef on CONFIG_MIPS_MT_SMP rather than CONFIG_MIPS_MTPaul Burton2015-09-301-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The CONFIG_MIPS_MT symbol can be selected by CONFIG_MIPS_VPE_LOADER in addition to CONFIG_MIPS_MT_SMP. We only want MT code in the CPS SMP boot vector if we're using MT for SMP. Thus switch the config symbol we ifdef against to CONFIG_MIPS_MT_SMP. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Markos Chandras <markos.chandras@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: <stable@vger.kernel.org> # 3.16+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/10867/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * | | MIPS: CPS: Don't include MT code in non-MT kernels.Paul Burton2015-09-301-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The MT-specific code in mips_cps_boot_vpes can safely be omitted from kernels which don't support MT, with the default VPE==0 case being used as it would be after the has_mt (Config3.MT) check failed at runtime. Discarding the code entirely will save us a few bytes & allow cleaner handling of MT ASE instructions by later patches. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Markos Chandras <markos.chandras@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: <stable@vger.kernel.org> # 3.16+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/10866/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * | | MIPS: CPS: Stop dangling delay slot from has_mt.Paul Burton2015-09-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The has_mt macro ended with a branch, leaving its callers with a delay slot that would be executed if Config3.MT is not set. However it would not be executed if Config3 (or earlier Config registers) don't exist which makes it somewhat inconsistent at best. Fill the delay slot in the macro & fix the mips_cps_boot_vpes caller appropriately. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Markos Chandras <markos.chandras@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: <stable@vger.kernel.org> # 3.16+ Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/10865/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * | | MIPS: dma-default: Fix 32-bit fall back to GFP_DMAJames Hogan2015-09-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If there is a DMA zone (usually 24bit = 16MB I believe), but no DMA32 zone, as is the case for some 32-bit kernels, then massage_gfp_flags() will cause DMA memory allocated for devices with a 32..63-bit coherent_dma_mask to fall back to using __GFP_DMA, even though there may only be 32-bits of physical address available anyway. Correct that case to compare against a mask the size of phys_addr_t instead of always using a 64-bit mask. Signed-off-by: James Hogan <james.hogan@imgtec.com> Fixes: a2e715a86c6d ("MIPS: DMA: Fix computation of DMA flags from device's coherent_dma_mask.") Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # 2.6.36+ Patchwork: https://patchwork.linux-mips.org/patch/9610/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * | | MIPS: Wire up userfaultfd and membarrier syscalls.Ralf Baechle2015-09-305-6/+20
| | | | | | | | | | | | | | | | | | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * | | | Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds2015-10-043-3/+21
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: "This update contains: - Fix for a long standing race affecting /proc/irq/NNN - One line fix for ARM GICV3-ITS counting the wrong data - Warning silencing in ARM GICV3-ITS. Another GCC trying to be overly clever issue" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/gic-v3-its: Count additional LPIs for the aliased devices irqchip/gic-v3-its: Silence warning when its_lpi_alloc_chunks gets inlined genirq: Fix race in register_irq_proc()
| | * | | | irqchip/gic-v3-its: Count additional LPIs for the aliased devicesMarc Zyngier2015-10-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When configuring the interrupt mapping for a new device, we iterate over all the possible aliases to account for their maximum MSI allocation. This was introduced by e8137f4f5088 ("irqchip: gicv3-its: Iterate over PCI aliases to generate ITS configuration"). Turns out that the code doing that is a bit braindead, and repeatedly accounts for the same device over and over. Fix this by counting the actual alias that is passed to us by the core code. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Alex Shi <alex.shi@linaro.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: David Daney <ddaney.cavm@gmail.com> Cc: Jason Cooper <jason@lakedaemon.net> Link: http://lkml.kernel.org/r/1443800646-8074-3-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | irqchip/gic-v3-its: Silence warning when its_lpi_alloc_chunks gets inlinedMarc Zyngier2015-10-021-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | More agressive inlining in recent versions of GCC have uncovered a new set of warnings: drivers/irqchip/irq-gic-v3-its.c: In function its_msi_prepare: drivers/irqchip/irq-gic-v3-its.c:1148:26: warning: lpi_base may be used uninitialized in this function [-Wmaybe-uninitialized] dev->event_map.lpi_base = lpi_base; ^ drivers/irqchip/irq-gic-v3-its.c:1116:6: note: lpi_base was declared here int lpi_base; ^ drivers/irqchip/irq-gic-v3-its.c:1149:25: warning: nr_lpis may be used uninitialized in this function [-Wmaybe-uninitialized] dev->event_map.nr_lpis = nr_lpis; ^ drivers/irqchip/irq-gic-v3-its.c:1117:6: note: nr_lpis was declared here int nr_lpis; ^ The warning is fairly benign (there is no code path that could actually use uninitialized variables), but let's silence it anyway by zeroing the variables on the error path. Reported-by: Alex Shi <alex.shi@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: David Daney <ddaney.cavm@gmail.com> Cc: Jason Cooper <jason@lakedaemon.net> Link: http://lkml.kernel.org/r/1443800646-8074-2-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | genirq: Fix race in register_irq_proc()Ben Hutchings2015-10-011-2/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Per-IRQ directories in procfs are created only when a handler is first added to the irqdesc, not when the irqdesc is created. In the case of a shared IRQ, multiple tasks can race to create a directory. This race condition seems to have been present forever, but is easier to hit with async probing. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Link: http://lkml.kernel.org/r/1443266636.2004.2.camel@decadent.org.uk Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org
| * | | | | Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2015-10-039-65/+69
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Fixes all around the map: W+X kernel mapping fix, WCHAN fixes, two build failure fixes for corner case configs, x32 header fix and a speling fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/headers/uapi: Fix __BITS_PER_LONG value for x32 builds x86/mm: Set NX on gap between __ex_table and rodata x86/kexec: Fix kexec crash in syscall kexec_file_load() x86/process: Unify 32bit and 64bit implementations of get_wchan() x86/process: Add proper bound checks in 64bit get_wchan() x86, efi, kasan: Fix build failure on !KASAN && KMEMCHECK=y kernels x86/hyperv: Fix the build in the !CONFIG_KEXEC_CORE case x86/cpufeatures: Correct spelling of the HWP_NOTIFY flag
| | * | | | | x86/headers/uapi: Fix __BITS_PER_LONG value for x32 buildsBen Hutchings2015-10-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On x32, gcc predefines __x86_64__ but long is only 32-bit. Use __ILP32__ to distinguish x32. Fixes this compiler error in perf: tools/include/asm-generic/bitops/__ffs.h: In function '__ffs': tools/include/asm-generic/bitops/__ffs.h:19:8: error: right shift count >= width of type [-Werror=shift-count-overflow] word >>= 32; ^ This isn't sufficient to build perf for x32, though. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: 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 Link: http://lkml.kernel.org/r/1443660043.2730.15.camel@decadent.org.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/mm: Set NX on gap between __ex_table and rodataStephen Smalley2015-10-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unused space between the end of __ex_table and the start of rodata can be left W+x in the kernel page tables. Extend the setting of the NX bit to cover this gap by starting from text_end rather than rodata_start. Before: ---[ High Kernel Mapping ]--- 0xffffffff80000000-0xffffffff81000000 16M pmd 0xffffffff81000000-0xffffffff81600000 6M ro PSE GLB x pmd 0xffffffff81600000-0xffffffff81754000 1360K ro GLB x pte 0xffffffff81754000-0xffffffff81800000 688K RW GLB x pte 0xffffffff81800000-0xffffffff81a00000 2M ro PSE GLB NX pmd 0xffffffff81a00000-0xffffffff81b3b000 1260K ro GLB NX pte 0xffffffff81b3b000-0xffffffff82000000 4884K RW GLB NX pte 0xffffffff82000000-0xffffffff82200000 2M RW PSE GLB NX pmd 0xffffffff82200000-0xffffffffa0000000 478M pmd After: ---[ High Kernel Mapping ]--- 0xffffffff80000000-0xffffffff81000000 16M pmd 0xffffffff81000000-0xffffffff81600000 6M ro PSE GLB x pmd 0xffffffff81600000-0xffffffff81754000 1360K ro GLB x pte 0xffffffff81754000-0xffffffff81800000 688K RW GLB NX pte 0xffffffff81800000-0xffffffff81a00000 2M ro PSE GLB NX pmd 0xffffffff81a00000-0xffffffff81b3b000 1260K ro GLB NX pte 0xffffffff81b3b000-0xffffffff82000000 4884K RW GLB NX pte 0xffffffff82000000-0xffffffff82200000 2M RW PSE GLB NX pmd 0xffffffff82200000-0xffffffffa0000000 478M pmd Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Kees Cook <keescook@chromium.org> Cc: <stable@vger.kernel.org> Cc: 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 Link: http://lkml.kernel.org/r/1443704662-3138-1-git-send-email-sds@tycho.nsa.gov Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/kexec: Fix kexec crash in syscall kexec_file_load()Lee, Chun-Yi2015-10-021-4/+3Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The original bug is a page fault crash that sometimes happens on big machines when preparing ELF headers: BUG: unable to handle kernel paging request at ffffc90613fc9000 IP: [<ffffffff8103d645>] prepare_elf64_ram_headers_callback+0x165/0x260 The bug is caused by us under-counting the number of memory ranges and subsequently not allocating enough ELF header space for them. The bug is typically masked on smaller systems, because the ELF header allocation is rounded up to the next page. This patch modifies the code in fill_up_crash_elf_data() by using walk_system_ram_res() instead of walk_system_ram_range() to correctly count the max number of crash memory ranges. That's because the walk_system_ram_range() filters out small memory regions that reside in the same page, but walk_system_ram_res() does not. Here's how I found the bug: After tracing prepare_elf64_headers() and prepare_elf64_ram_headers_callback(), the code uses walk_system_ram_res() to fill-in crash memory regions information to the program header, so it counts those small memory regions that reside in a page area. But, when the kernel was using walk_system_ram_range() in fill_up_crash_elf_data() to count the number of crash memory regions, it filters out small regions. I printed those small memory regions, for example: kexec: Get nr_ram ranges. vaddr=0xffff880077592258 paddr=0x77592258, sz=0xdc0 Based on the code in walk_system_ram_range(), this memory region will be filtered out: pfn = (0x77592258 + 0x1000 - 1) >> 12 = 0x77593 end_pfn = (0x77592258 + 0xfc0 -1 + 1) >> 12 = 0x77593 end_pfn - pfn = 0x77593 - 0x77593 = 0 <=== if (end_pfn > pfn) is FALSE So, the max_nr_ranges that's counted by the kernel doesn't include small memory regions - causing us to under-allocate the required space. That causes the page fault crash that happens in a later code path when preparing ELF headers. This bug is not easy to reproduce on small machines that have few CPUs, because the allocated page aligned ELF buffer has more free space to cover those small memory regions' PT_LOAD headers. Signed-off-by: Lee, Chun-Yi <jlee@suse.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Takashi Iwai <tiwai@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: kexec@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1443531537-29436-1-git-send-email-jlee@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | Merge remote-tracking branch 'tglx/x86/urgent' into x86/urgentIngo Molnar2015-10-013-52/+55
| | |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pick up the WCHAN fixes from Thomas. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | | | x86/process: Unify 32bit and 64bit implementations of get_wchan()Thomas Gleixner2015-09-303-84/+55Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The stack layout and the functionality is identical. Use the 64bit version for all of x86. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: kasan-dev <kasan-dev@googlegroups.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de> Link: http://lkml.kernel.org/r/20150930083302.779694618@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | | * | | | | x86/process: Add proper bound checks in 64bit get_wchan()Thomas Gleixner2015-09-301-10/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dmitry Vyukov reported the following using trinity and the memory error detector AddressSanitizer (https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel). [ 124.575597] ERROR: AddressSanitizer: heap-buffer-overflow on address ffff88002e280000 [ 124.576801] ffff88002e280000 is located 131938492886538 bytes to the left of 28857600-byte region [ffffffff81282e0a, ffffffff82e0830a) [ 124.578633] Accessed by thread T10915: [ 124.579295] inlined in describe_heap_address ./arch/x86/mm/asan/report.c:164 [ 124.579295] #0 ffffffff810dd277 in asan_report_error ./arch/x86/mm/asan/report.c:278 [ 124.580137] #1 ffffffff810dc6a0 in asan_check_region ./arch/x86/mm/asan/asan.c:37 [ 124.581050] #2 ffffffff810dd423 in __tsan_read8 ??:0 [ 124.581893] #3 ffffffff8107c093 in get_wchan ./arch/x86/kernel/process_64.c:444 The address checks in the 64bit implementation of get_wchan() are wrong in several ways: - The lower bound of the stack is not the start of the stack page. It's the start of the stack page plus sizeof (struct thread_info) - The upper bound must be: top_of_stack - TOP_OF_KERNEL_STACK_PADDING - 2 * sizeof(unsigned long). The 2 * sizeof(unsigned long) is required because the stack pointer points at the frame pointer. The layout on the stack is: ... IP FP ... IP FP. So we need to make sure that both IP and FP are in the bounds. Fix the bound checks and get rid of the mix of numeric constants, u64 and unsigned long. Making all unsigned long allows us to use the same function for 32bit as well. Use READ_ONCE() when accessing the stack. This does not prevent a concurrent wakeup of the task and the stack changing, but at least it avoids TOCTOU. Also check task state at the end of the loop. Again that does not prevent concurrent changes, but it avoids walking for nothing. Add proper comments while at it. Reported-by: Dmitry Vyukov <dvyukov@google.com> Reported-by: Sasha Levin <sasha.levin@oracle.com> Based-on-patch-from: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: kasan-dev <kasan-dev@googlegroups.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20150930083302.694788319@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | | | x86, efi, kasan: Fix build failure on !KASAN && KMEMCHECK=y kernelsAndrey Ryabinin2015-09-301-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With KMEMCHECK=y, KASAN=n we get this build failure: arch/x86/platform/efi/efi.c:673:3: error: implicit declaration of function ‘memcpy’ [-Werror=implicit-function-declaration] arch/x86/platform/efi/efi_64.c:139:2: error: implicit declaration of function ‘memcpy’ [-Werror=implicit-function-declaration] arch/x86/include/asm/desc.h:121:2: error: implicit declaration of function ‘memcpy’ [-Werror=implicit-function-declaration] Don't #undef memcpy if KASAN=n. Reported-by: Ingo Molnar <mingo@kernel.org> Reported-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt.fleming@intel.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 769a8089c1fd ("x86, efi, kasan: #undef memset/memcpy/memmove per arch") Link: http://lkml.kernel.org/r/1443544814-20122-1-git-send-email-ryabinin.a.a@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | | Merge tag 'v4.3-rc3' into x86/urgent, before applying dependent fixIngo Molnar2015-09-30434-2576/+4956
| | |\ \ \ \ \ \ | | | |/ / / / / | | |/| | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | | x86/hyperv: Fix the build in the !CONFIG_KEXEC_CORE caseVitaly Kuznetsov2015-09-301-5/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Recent changes in the Hyper-V driver: b4370df2b1f5 ("Drivers: hv: vmbus: add special crash handler") broke the build when CONFIG_KEXEC_CORE is not set: arch/x86/built-in.o: In function `hv_machine_crash_shutdown': arch/x86/kernel/cpu/mshyperv.c:112: undefined reference to `native_machine_crash_shutdown' Decorate all kexec related code with #ifdef CONFIG_KEXEC_CORE. Reported-by: Jim Davis <jim.epost@gmail.com> Reported-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: devel@linuxdriverproject.org Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1443002577-25370-1-git-send-email-vkuznets@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | | x86/cpufeatures: Correct spelling of the HWP_NOTIFY flagKristen Carlson Accardi2015-09-232-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because noitification just isn't right. Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Cc: rjw@rjwysocki.net Link: http://lkml.kernel.org/r/1442944296-11737-1-git-send-email-kristen@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-07-11 17:17:55 +0200