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2014-11-21x86: finish user fault error path with fatal signalJohannes Weiner
commit 3a13c4d761b4b979ba8767f42345fed3274991b0 upstream. The x86 fault handler bails in the middle of error handling when the task has a fatal signal pending. For a subsequent patch this is a problem in OOM situations because it relies on pagefault_out_of_memory() being called even when the task has been killed, to perform proper per-task OOM state unwinding. Shortcutting the fault like this is a rather minor optimization that saves a few instructions in rare cases. Just remove it for user-triggered faults. Use the opportunity to split the fault retry handling from actual fault errors and add locking documentation that reads suprisingly similar to ARM's. 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> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21arch: mm: pass userspace fault flag to generic fault handlerJohannes Weiner
commit 759496ba6407c6994d6a5ce3a5e74937d7816208 upstream. 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: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21arch: mm: do not invoke OOM killer on kernel fault OOMJohannes Weiner
commit 871341023c771ad233620b7a1fb3d9c7031c4e5c upstream. 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> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21arch: mm: remove obsolete init OOM protectionJohannes Weiner
commit 94bce453c78996cc4373d5da6cfabe07fcc6d9f9 upstream. 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> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21mm: invoke oom-killer from remaining unconverted page fault handlersJohannes Weiner
commit 609838cfed972d49a65aac7923a9ff5cbe482e30 upstream. A few remaining architectures directly kill the page faulting task in an out of memory situation. This is usually not a good idea since that task might not even use a significant amount of memory and so may not be the optimal victim to resolve the situation. Since 2.6.29's 1c0fe6e ("mm: invoke oom-killer from page fault") there is a hook that architecture page fault handlers are supposed to call to invoke the OOM killer and let it pick the right task to kill. Convert the remaining architectures over to this hook. To have the previous behavior of simply taking out the faulting task the vm.oom_kill_allocating_task sysctl can be set to 1. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc bits] Cc: James Hogan <james.hogan@imgtec.com> Cc: David Howells <dhowells@redhat.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chen Liqin <liqin.chen@sunplusct.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21KVM: x86: Don't report guest userspace emulation error to userspaceNadav Amit
commit a2b9e6c1a35afcc0973acb72e591c714e78885ff upstream. Commit fc3a9157d314 ("KVM: X86: Don't report L2 emulation failures to user-space") disabled the reporting of L2 (nested guest) emulation failures to userspace due to race-condition between a vmexit and the instruction emulator. The same rational applies also to userspace applications that are permitted by the guest OS to access MMIO area or perform PIO. This patch extends the current behavior - of injecting a #UD instead of reporting it to userspace - also for guest userspace code. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21ARM: Correct BUG() assembly to ensure it is endian-agnosticBen Dooks
commit 63328070eff2f4fd730c86966a0dbc976147c39f upstream. Currently BUG() uses .word or .hword to create the necessary illegal instructions. However if we are building BE8 then these get swapped by the linker into different illegal instructions in the text. This means that the BUG() macro does not get trapped properly. Change to using <asm/opcodes.h> to provide the necessary ARM instruction building as we cannot rely on gcc/gas having the `.inst` instructions which where added to try and resolve this issue (reported by Dave Martin <Dave.Martin@arm.com>). Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21perf/x86/intel: Use proper dTLB-load-misses event on IvyBridgeVince Weaver
commit 1996388e9f4e3444db8273bc08d25164d2967c21 upstream. This was discussed back in February: https://lkml.org/lkml/2014/2/18/956 But I never saw a patch come out of it. On IvyBridge we share the SandyBridge cache event tables, but the dTLB-load-miss event is not compatible. Patch it up after the fact to the proper DTLB_LOAD_MISSES.DEMAND_LD_MISS_CAUSES_A_WALK Signed-off-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1407141528200.17214@vincent-weaver-1.umelst.maine.edu Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Hou Pengyang <houpengyang@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21MIPS: Fix forgotten preempt_enable() when CPU has inclusive pcachesYoichi Yuasa
commit 5596b0b245fb9d2cefb5023b11061050351c1398 upstream. [ 1.904000] BUG: scheduling while atomic: swapper/1/0x00000002 [ 1.908000] Modules linked in: [ 1.916000] CPU: 0 PID: 1 Comm: swapper Not tainted 3.12.0-rc2-lemote-los.git-5318619-dirty #1 [ 1.920000] Stack : 0000000031aac000 ffffffff810d0000 0000000000000052 ffffffff802730a4 0000000000000000 0000000000000001 ffffffff810cdf90 ffffffff810d0000 ffffffff8068b968 ffffffff806f5537 ffffffff810cdf90 980000009f0782e8 0000000000000001 ffffffff80720000 ffffffff806b0000 980000009f078000 980000009f290000 ffffffff805f312c 980000009f05b5d8 ffffffff80233518 980000009f05b5e8 ffffffff80274b7c 980000009f078000 ffffffff8068b968 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 980000009f05b520 0000000000000000 ffffffff805f2f6c 0000000000000000 ffffffff80700000 ffffffff80700000 ffffffff806fc758 ffffffff80700000 ffffffff8020be98 ffffffff806fceb0 ffffffff805f2f6c ... [ 2.028000] Call Trace: [ 2.032000] [<ffffffff8020be98>] show_stack+0x80/0x98 [ 2.036000] [<ffffffff805f2f6c>] __schedule_bug+0x44/0x6c [ 2.040000] [<ffffffff805fac58>] __schedule+0x518/0x5b0 [ 2.044000] [<ffffffff805f8a58>] schedule_timeout+0x128/0x1f0 [ 2.048000] [<ffffffff80240314>] msleep+0x3c/0x60 [ 2.052000] [<ffffffff80495400>] do_probe+0x238/0x3a8 [ 2.056000] [<ffffffff804958b0>] ide_probe_port+0x340/0x7e8 [ 2.060000] [<ffffffff80496028>] ide_host_register+0x2d0/0x7a8 [ 2.064000] [<ffffffff8049c65c>] ide_pci_init_two+0x4e4/0x790 [ 2.068000] [<ffffffff8049f9b8>] amd74xx_probe+0x148/0x2c8 [ 2.072000] [<ffffffff803f571c>] pci_device_probe+0xc4/0x130 [ 2.076000] [<ffffffff80478f60>] driver_probe_device+0x98/0x270 [ 2.080000] [<ffffffff80479298>] __driver_attach+0xe0/0xe8 [ 2.084000] [<ffffffff80476ab0>] bus_for_each_dev+0x78/0xe0 [ 2.088000] [<ffffffff80478468>] bus_add_driver+0x230/0x310 [ 2.092000] [<ffffffff80479b44>] driver_register+0x84/0x158 [ 2.096000] [<ffffffff80200504>] do_one_initcall+0x104/0x160 Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org> Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi> Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi> Cc: linux-mips@linux-mips.org Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org> Patchwork: https://patchwork.linux-mips.org/patch/5941/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: Alexandre Oliva <lxoliva@fsfla.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21ARM: probes: fix instruction fetch order with <asm/opcodes.h>Ben Dooks
commit 888be25402021a425da3e85e2d5a954d7509286e upstream. If we are running BE8, the data and instruction endianness do not match, so use <asm/opcodes.h> to correctly translate memory accesses into ARM instructions. Acked-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> [taras.kondratiuk@linaro.org: fixed Thumb instruction fetch order] Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org> [wangnan: backport to 3.10 and 3.14: - adjust context - backport all changes on arch/arm/kernel/probes.c to arch/arm/kernel/kprobes-common.c since we don't have commit c18377c303787ded44b7decd7dee694db0f205e9. - After the above adjustments, becomes same to Taras Kondratiuk's original patch: http://lists.linaro.org/pipermail/linaro-kernel/2014-January/010346.html ] Signed-off-by: Wang Nan <wangnan0@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21parisc: Use compat layer for msgctl, shmat, shmctl and semtimedop syscallsHelge Deller
commit 2fe749f50b0bec07650ef135b29b1f55bf543869 upstream. Switch over the msgctl, shmat, shmctl and semtimedop syscalls to use the compat layer. The problem was found with the debian procenv package, which called shmctl(0, SHM_INFO, &info); in which the shmctl syscall then overwrote parts of the surrounding areas on the stack on which the info variable was stored and thus lead to a segfault later on. Additionally fix the definition of struct shminfo64 to use unsigned longs like the other architectures. This has no impact on userspace since we only have a 32bit userspace up to now. Signed-off-by: Helge Deller <deller@gmx.de> Cc: John David Anglin <dave.anglin@bell.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21arm64: __clear_user: handle exceptions on strbKyle McMartin
commit 97fc15436b36ee3956efad83e22a557991f7d19d upstream. ARM64 currently doesn't fix up faults on the single-byte (strb) case of __clear_user... which means that we can cause a nasty kernel panic as an ordinary user with any multiple PAGE_SIZE+1 read from /dev/zero. i.e.: dd if=/dev/zero of=foo ibs=1 count=1 (or ibs=65537, etc.) This is a pretty obscure bug in the general case since we'll only __do_kernel_fault (since there's no extable entry for pc) if the mmap_sem is contended. However, with CONFIG_DEBUG_VM enabled, we'll always fault. if (!down_read_trylock(&mm->mmap_sem)) { if (!user_mode(regs) && !search_exception_tables(regs->pc)) goto no_context; retry: down_read(&mm->mmap_sem); } else { /* * The above down_read_trylock() might have succeeded in * which * case, we'll have missed the might_sleep() from * down_read(). */ might_sleep(); if (!user_mode(regs) && !search_exception_tables(regs->pc)) goto no_context; } Fix that by adding an extable entry for the strb instruction, since it touches user memory, similar to the other stores in __clear_user. Signed-off-by: Kyle McMartin <kyle@redhat.com> Reported-by: Miloš Prchlík <mprchlik@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21ARM: 8198/1: make kuser helpers depend on MMUNathan Lynch
commit 08b964ff3c51b10aaf2e6ba639f40054c09f0f7a upstream. The kuser helpers page is not set up on non-MMU systems, so it does not make sense to allow CONFIG_KUSER_HELPERS to be enabled when CONFIG_MMU=n. Allowing it to be set on !MMU results in an oops in set_tls (used in execve and the arm_syscall trap handler): Unhandled exception: IPSR = 00000005 LR = fffffff1 CPU: 0 PID: 1 Comm: swapper Not tainted 3.18.0-rc1-00041-ga30465a #216 task: 8b838000 ti: 8b82a000 task.ti: 8b82a000 PC is at flush_thread+0x32/0x40 LR is at flush_thread+0x21/0x40 pc : [<8f00157a>] lr : [<8f001569>] psr: 4100000b sp : 8b82be20 ip : 00000000 fp : 8b83c000 r10: 00000001 r9 : 88018c84 r8 : 8bb85000 r7 : 8b838000 r6 : 00000000 r5 : 8bb77400 r4 : 8b82a000 r3 : ffff0ff0 r2 : 8b82a000 r1 : 00000000 r0 : 88020354 xPSR: 4100000b CPU: 0 PID: 1 Comm: swapper Not tainted 3.18.0-rc1-00041-ga30465a #216 [<8f002bc1>] (unwind_backtrace) from [<8f002033>] (show_stack+0xb/0xc) [<8f002033>] (show_stack) from [<8f00265b>] (__invalid_entry+0x4b/0x4c) As best I can tell this issue existed for the set_tls ARM syscall before commit fbfb872f5f41 "ARM: 8148/1: flush TLS and thumbee register state during exec" consolidated the TLS manipulation code into the set_tls helper function, but now that we're using it to flush register state during execve, !MMU users encounter the oops at the first exec. Prevent CONFIG_MMU=n configurations from enabling CONFIG_KUSER_HELPERS. Fixes: fbfb872f5f41 (ARM: 8148/1: flush TLS and thumbee register state during exec) Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com> Reported-by: Stefan Agner <stefan@agner.ch> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21xtensa: re-wire umount syscall to sys_oldumountMax Filippov
commit 2651cc6974d47fc43bef1cd8cd26966e4f5ba306 upstream. Userspace actually passes single parameter (path name) to the umount syscall, so new umount just fails. Fix it by requesting old umount syscall implementation and re-wiring umount to it. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21x86, x32, audit: Fix x32's AUDIT_ARCH wrt auditAndy Lutomirski
commit 81f49a8fd7088cfcb588d182eeede862c0e3303e upstream. is_compat_task() is the wrong check for audit arch; the check should be is_ia32_task(): x32 syscalls should be AUDIT_ARCH_X86_64, not AUDIT_ARCH_I386. CONFIG_AUDITSYSCALL is currently incompatible with x32, so this has no visible effect. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/a0138ed8c709882aec06e4acc30bfa9b623b8717.1409954077.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21sparc32: Implement xchg and atomic_xchg using ATOMIC_HASH locksAndreas Larsson
[ Upstream commit 1a17fdc4f4ed06b63fac1937470378a5441a663a ] Atomicity between xchg and cmpxchg cannot be guaranteed when xchg is implemented with a swap and cmpxchg is implemented with locks. Without this, e.g. mcs_spin_lock and mcs_spin_unlock are broken. Signed-off-by: Andreas Larsson <andreas@gaisler.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21sparc64: Do irq_{enter,exit}() around generic_smp_call_function*().David S. Miller
[ Upstream commit ab5c780913bca0a5763ca05dd5c2cb5cb08ccb26 ] Otherwise rcu_irq_{enter,exit}() do not happen and we get dumps like: ==================== [ 188.275021] =============================== [ 188.309351] [ INFO: suspicious RCU usage. ] [ 188.343737] 3.18.0-rc3-00068-g20f3963-dirty #54 Not tainted [ 188.394786] ------------------------------- [ 188.429170] include/linux/rcupdate.h:883 rcu_read_lock() used illegally while idle! [ 188.505235] other info that might help us debug this: [ 188.554230] RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 0 [ 188.637587] RCU used illegally from extended quiescent state! [ 188.690684] 3 locks held by swapper/7/0: [ 188.721932] #0: (&x->wait#11){......}, at: [<0000000000495de8>] complete+0x8/0x60 [ 188.797994] #1: (&p->pi_lock){-.-.-.}, at: [<000000000048510c>] try_to_wake_up+0xc/0x400 [ 188.881343] #2: (rcu_read_lock){......}, at: [<000000000048a910>] select_task_rq_fair+0x90/0xb40 [ 188.973043]stack backtrace: [ 188.993879] CPU: 7 PID: 0 Comm: swapper/7 Not tainted 3.18.0-rc3-00068-g20f3963-dirty #54 [ 189.076187] Call Trace: [ 189.089719] [0000000000499360] lockdep_rcu_suspicious+0xe0/0x100 [ 189.147035] [000000000048a99c] select_task_rq_fair+0x11c/0xb40 [ 189.202253] [00000000004852d8] try_to_wake_up+0x1d8/0x400 [ 189.252258] [000000000048554c] default_wake_function+0xc/0x20 [ 189.306435] [0000000000495554] __wake_up_common+0x34/0x80 [ 189.356448] [00000000004955b4] __wake_up_locked+0x14/0x40 [ 189.406456] [0000000000495e08] complete+0x28/0x60 [ 189.448142] [0000000000636e28] blk_end_sync_rq+0x8/0x20 [ 189.496057] [0000000000639898] __blk_mq_end_request+0x18/0x60 [ 189.550249] [00000000006ee014] scsi_end_request+0x94/0x180 [ 189.601286] [00000000006ee334] scsi_io_completion+0x1d4/0x600 [ 189.655463] [00000000006e51c4] scsi_finish_command+0xc4/0xe0 [ 189.708598] [00000000006ed958] scsi_softirq_done+0x118/0x140 [ 189.761735] [00000000006398ec] __blk_mq_complete_request_remote+0xc/0x20 [ 189.827383] [00000000004c75d0] generic_smp_call_function_single_interrupt+0x150/0x1c0 [ 189.906581] [000000000043e514] smp_call_function_single_client+0x14/0x40 ==================== Based almost entirely upon a patch by Paul E. McKenney. Reported-by: Meelis Roos <mroos@linux.ee> Tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21sparc64: Fix crashes in schizo_pcierr_intr_other().David S. Miller
[ Upstream commit 7da89a2a3776442a57e918ca0b8678d1b16a7072 ] Meelis Roos reports crashes during bootup on a V480 that look like this: ==================== [ 61.300577] PCI: Scanning PBM /pci@9,600000 [ 61.304867] schizo f009b070: PCI host bridge to bus 0003:00 [ 61.310385] pci_bus 0003:00: root bus resource [io 0x7ffe9000000-0x7ffe9ffffff] (bus address [0x0000-0xffffff]) [ 61.320515] pci_bus 0003:00: root bus resource [mem 0x7fb00000000-0x7fbffffffff] (bus address [0x00000000-0xffffffff]) [ 61.331173] pci_bus 0003:00: root bus resource [bus 00] [ 61.385344] Unable to handle kernel NULL pointer dereference [ 61.390970] tsk->{mm,active_mm}->context = 0000000000000000 [ 61.396515] tsk->{mm,active_mm}->pgd = fff000b000002000 [ 61.401716] \|/ ____ \|/ [ 61.401716] "@'/ .. \`@" [ 61.401716] /_| \__/ |_\ [ 61.401716] \__U_/ [ 61.416362] swapper/0(0): Oops [#1] [ 61.419837] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.18.0-rc1-00422-g2cc9188-dirty #24 [ 61.427975] task: fff000b0fd8e9c40 ti: fff000b0fd928000 task.ti: fff000b0fd928000 [ 61.435426] TSTATE: 0000004480e01602 TPC: 00000000004455e4 TNPC: 00000000004455e8 Y: 00000000 Not tainted [ 61.445230] TPC: <schizo_pcierr_intr+0x104/0x560> [ 61.449897] g0: 0000000000000000 g1: 0000000000000000 g2: 0000000000a10f78 g3: 000000000000000a [ 61.458563] g4: fff000b0fd8e9c40 g5: fff000b0fdd82000 g6: fff000b0fd928000 g7: 000000000000000a [ 61.467229] o0: 000000000000003d o1: 0000000000000000 o2: 0000000000000006 o3: fff000b0ffa5fc7e [ 61.475894] o4: 0000000000060000 o5: c000000000000000 sp: fff000b0ffa5f3c1 ret_pc: 00000000004455cc [ 61.484909] RPC: <schizo_pcierr_intr+0xec/0x560> [ 61.489500] l0: fff000b0fd8e9c40 l1: 0000000000a20800 l2: 0000000000000000 l3: 000000000119a430 [ 61.498164] l4: 0000000001742400 l5: 00000000011cfbe0 l6: 00000000011319c0 l7: fff000b0fd8ea348 [ 61.506830] i0: 0000000000000000 i1: fff000b0fdb34000 i2: 0000000320000000 i3: 0000000000000000 [ 61.515497] i4: 00060002010b003f i5: 0000040004e02000 i6: fff000b0ffa5f481 i7: 00000000004a9920 [ 61.524175] I7: <handle_irq_event_percpu+0x40/0x140> [ 61.529099] Call Trace: [ 61.531531] [00000000004a9920] handle_irq_event_percpu+0x40/0x140 [ 61.537681] [00000000004a9a58] handle_irq_event+0x38/0x80 [ 61.543145] [00000000004ac77c] handle_fasteoi_irq+0xbc/0x200 [ 61.548860] [00000000004a9084] generic_handle_irq+0x24/0x40 [ 61.554500] [000000000042be0c] handler_irq+0xac/0x100 ==================== The problem is that pbm->pci_bus->self is NULL. This code is trying to go through the standard PCI config space interfaces to read the PCI controller's PCI_STATUS register. This doesn't work, because we more often than not do not enumerate the PCI controller as a bonafide PCI device during the OF device node scan. Therefore bus->self remains NULL. Existing common code for PSYCHO and PSYCHO-like PCI controllers handles this properly, by doing the config space access directly. Do the same here, pbm->pci_ops->{read,write}(). Reported-by: Meelis Roos <mroos@linux.ee> Tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21vio: fix reuse of vio_dring slotDwight Engen
[ Upstream commit d0aedcd4f14a22e23b313f42b7e6e6ebfc0fbc31 ] vio_dring_avail() will allow use of every dring entry, but when the last entry is allocated then dr->prod == dr->cons which is indistinguishable from the ring empty condition. This causes the next allocation to reuse an entry. When this happens in sunvdc, the server side vds driver begins nack'ing the messages and ends up resetting the ldc channel. This problem does not effect sunvnet since it checks for < 2. The fix here is to just never allocate the very last dring slot so that full and empty are not the same condition. The request start path was changed to check for the ring being full a bit earlier, and to stop the blk_queue if there is no space left. The blk_queue will be restarted once the ring is only half full again. The number of ring entries was increased to 512 which matches the sunvnet and Solaris vdc drivers, and greatly reduces the frequency of hitting the ring full condition and the associated blk_queue stop/starting. The checks in sunvent were adjusted to account for vio_dring_avail() returning 1 less. Orabug: 19441666 OraBZ: 14983 Signed-off-by: Dwight Engen <dwight.engen@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21sunvdc: add cdrom and v1.1 protocol supportAllen Pais
[ Upstream commit 9bce21828d54a95143f1b74619705c2dd8e88b92 ] Interpret the media type from v1.1 protocol to support CDROM/DVD. For v1.0 protocol, a disk's size continues to be calculated from the geometry returned by the vdisk server. The geometry returned by the server can be less than the actual number of sectors available in the backing image/device due to the rounding in the division used to compute the geometry in the vdisk server. In v1.1 protocol a disk's actual size in sectors is returned during the handshake. Use this size when v1.1 protocol is negotiated. Since this size will always be larger than the former geometry computed size, disks created under v1.0 will be forwards compatible to v1.1, but not vice versa. Signed-off-by: Dwight Engen <dwight.engen@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14x86, apic: Handle a bad TSC more gracefullyAndy Lutomirski
commit b47dcbdc5161d3d5756f430191e2840d9b855492 upstream. If the TSC is unusable or disabled, then this patch fixes: - Confusion while trying to clear old APIC interrupts. - Division by zero and incorrect programming of the TSC deadline timer. This fixes boot if the CPU has a TSC deadline timer but a missing or broken TSC. The failure to boot can be observed with qemu using -cpu qemu64,-tsc,+tsc-deadline This also happens to me in nested KVM for unknown reasons. With this patch, I can boot cleanly (although without a TSC). Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Bandan Das <bsd@redhat.com> Link: http://lkml.kernel.org/r/e2fa274e498c33988efac0ba8b7e3120f7f92d78.1413393027.git.luto@amacapital.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14MIPS: tlbex: Properly fix HUGE TLB Refill exception handlerDavid Daney
commit 9e0f162a36914937a937358fcb45e0609ef2bfc4 upstream. In commit 8393c524a25609 (MIPS: tlbex: Fix a missing statement for HUGETLB), the TLB Refill handler was fixed so that non-OCTEON targets would work properly with huge pages. The change was incorrect in that it broke the OCTEON case. The problem is shown here: xxx0: df7a0000 ld k0,0(k1) . . . xxxc0: df610000 ld at,0(k1) xxxc4: 335a0ff0 andi k0,k0,0xff0 xxxc8: e825ffcd bbit1 at,0x5,0x0 xxxcc: 003ad82d daddu k1,at,k0 . . . In the non-octeon case there is a destructive test for the huge PTE bit, and then at 0, $k0 is reloaded (that is what the 8393c524a25609 patch added). In the octeon case, we modify k1 in the branch delay slot, but we never need k0 again, so the new load is not needed, but since k1 is modified, if we do the load, we load from a garbage location and then get a nested TLB Refill, which is seen in userspace as either SIGBUS or SIGSEGV (depending on the garbage). The real fix is to only do this reloading if it is needed, and never where it is harmful. Signed-off-by: David Daney <david.daney@cavium.com> Cc: Huacai Chen <chenhc@lemote.com> Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/8151/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14ARC: Update order of registers in KGDB to match GDB 7.5Anton Kolesov
commit ebc0c74e76cec9c4dd860eb0ca1c0b39dc63c482 upstream. Order of registers has changed in GDB moving from 6.8 to 7.5. This patch updates KGDB to work properly with GDB 7.5, though makes it incompatible with 6.8. Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14ARC: [nsimosci] Allow "headless" models to bootVineet Gupta
commit 5c05483e2db91890faa9a7be0a831701a3f442d6 upstream. There are certain test configuration of virtual platform which don't have any real console device (uart/pgu). So add tty0 as a fallback console device to allow system to boot and be accessible via telnet Otherwise with ttyS0 as only console, but 8250 disabled in kernel build, init chokes. Reported-by: Anton Kolesov <akolesov@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14KVM: x86: Emulator fixes for eip canonical checks on near branchesNadav Amit
commit 234f3ce485d54017f15cf5e0699cff4100121601 upstream. Before changing rip (during jmp, call, ret, etc.) the target should be asserted to be canonical one, as real CPUs do. During sysret, both target rsp and rip should be canonical. If any of these values is noncanonical, a #GP exception should occur. The exception to this rule are syscall and sysenter instructions in which the assigned rip is checked during the assignment to the relevant MSRs. This patch fixes the emulator to behave as real CPUs do for near branches. Far branches are handled by the next patch. This fixes CVE-2014-3647. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14KVM: x86: Fix wrong masking on relative jump/callNadav Amit
commit 05c83ec9b73c8124555b706f6af777b10adf0862 upstream. Relative jumps and calls do the masking according to the operand size, and not according to the address size as the KVM emulator does today. This patch fixes KVM behavior. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14kvm: x86: don't kill guest on unknown exit reasonMichael S. Tsirkin
commit 2bc19dc3754fc066c43799659f0d848631c44cfe upstream. KVM_EXIT_UNKNOWN is a kvm bug, we don't really know whether it was triggered by a priveledged application. Let's not kill the guest: WARN and inject #UD instead. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14KVM: x86: Check non-canonical addresses upon WRMSRNadav Amit
commit 854e8bb1aa06c578c2c9145fa6bfe3680ef63b23 upstream. Upon WRMSR, the CPU should inject #GP if a non-canonical value (address) is written to certain MSRs. The behavior is "almost" identical for AMD and Intel (ignoring MSRs that are not implemented in either architecture since they would anyhow #GP). However, IA32_SYSENTER_ESP and IA32_SYSENTER_EIP cause #GP if non-canonical address is written on Intel but not on AMD (which ignores the top 32-bits). Accordingly, this patch injects a #GP on the MSRs which behave identically on Intel and AMD. To eliminate the differences between the architecutres, the value which is written to IA32_SYSENTER_ESP and IA32_SYSENTER_EIP is turned to canonical value before writing instead of injecting a #GP. Some references from Intel and AMD manuals: According to Intel SDM description of WRMSR instruction #GP is expected on WRMSR "If the source register contains a non-canonical address and ECX specifies one of the following MSRs: IA32_DS_AREA, IA32_FS_BASE, IA32_GS_BASE, IA32_KERNEL_GS_BASE, IA32_LSTAR, IA32_SYSENTER_EIP, IA32_SYSENTER_ESP." According to AMD manual instruction manual: LSTAR/CSTAR (SYSCALL): "The WRMSR instruction loads the target RIP into the LSTAR and CSTAR registers. If an RIP written by WRMSR is not in canonical form, a general-protection exception (#GP) occurs." IA32_GS_BASE and IA32_FS_BASE (WRFSBASE/WRGSBASE): "The address written to the base field must be in canonical form or a #GP fault will occur." IA32_KERNEL_GS_BASE (SWAPGS): "The address stored in the KernelGSbase MSR must be in canonical form." This patch fixes CVE-2014-3610. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14KVM: x86: Improve thread safety in pitAndy Honig
commit 2febc839133280d5a5e8e1179c94ea674489dae2 upstream. There's a race condition in the PIT emulation code in KVM. In __kvm_migrate_pit_timer the pit_timer object is accessed without synchronization. If the race condition occurs at the wrong time this can crash the host kernel. This fixes CVE-2014-3611. Signed-off-by: Andrew Honig <ahonig@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14KVM: x86: Prevent host from panicking on shared MSR writes.Andy Honig
commit 8b3c3104c3f4f706e99365c3e0d2aa61b95f969f upstream. The previous patch blocked invalid writes directly when the MSR is written. As a precaution, prevent future similar mistakes by gracefulling handle GPs caused by writes to shared MSRs. Signed-off-by: Andrew Honig <ahonig@google.com> [Remove parts obsoleted by Nadav's patch. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14x86, pageattr: Prevent overflow in slow_virt_to_phys() for X86_PAEDexuan Cui
commit d1cd1210834649ce1ca6bafe5ac25d2f40331343 upstream. pte_pfn() returns a PFN of long (32 bits in 32-PAE), so "long << PAGE_SHIFT" will overflow for PFNs above 4GB. Due to this issue, some Linux 32-PAE distros, running as guests on Hyper-V, with 5GB memory assigned, can't load the netvsc driver successfully and hence the synthetic network device can't work (we can use the kernel parameter mem=3000M to work around the issue). Cast pte_pfn() to phys_addr_t before shifting. Fixes: "commit d76565344512: x86, mm: Create slow_virt_to_phys()" Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: gregkh@linuxfoundation.org Cc: linux-mm@kvack.org Cc: olaf@aepfle.de Cc: apw@canonical.com Cc: jasowang@redhat.com Cc: dave.hansen@intel.com Cc: riel@redhat.com Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1414580017-27444-1-git-send-email-decui@microsoft.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14x86_64, entry: Fix out of bounds read on sysenterAndy Lutomirski
commit 653bc77af60911ead1f423e588f54fc2547c4957 upstream. Rusty noticed a Really Bad Bug (tm) in my NT fix. The entry code reads out of bounds, causing the NT fix to be unreliable. But, and this is much, much worse, if your stack is somehow just below the top of the direct map (or a hole), you read out of bounds and crash. Excerpt from the crash: [ 1.129513] RSP: 0018:ffff88001da4bf88 EFLAGS: 00010296 2b:* f7 84 24 90 00 00 00 testl $0x4000,0x90(%rsp) That read is deterministically above the top of the stack. I thought I even single-stepped through this code when I wrote it to check the offset, but I clearly screwed it up. Fixes: 8c7aa698baca ("x86_64, entry: Filter RFLAGS.NT on entry from userspace") Reported-by: Rusty Russell <rusty@ozlabs.org> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14x86_64, entry: Filter RFLAGS.NT on entry from userspaceAndy Lutomirski
commit 8c7aa698baca5e8f1ba9edb68081f1e7a1abf455 upstream. The NT flag doesn't do anything in long mode other than causing IRET to #GP. Oddly, CPL3 code can still set NT using popf. Entry via hardware or software interrupt clears NT automatically, so the only relevant entries are fast syscalls. If user code causes kernel code to run with NT set, then there's at least some (small) chance that it could cause trouble. For example, user code could cause a call to EFI code with NT set, and who knows what would happen? Apparently some games on Wine sometimes do this (!), and, if an IRET return happens, they will segfault. That segfault cannot be handled, because signal delivery fails, too. This patch programs the CPU to clear NT on entry via SYSCALL (both 32-bit and 64-bit, by my reading of the AMD APM), and it clears NT in software on entry via SYSENTER. To save a few cycles, this borrows a trick from Jan Beulich in Xen: it checks whether NT is set before trying to clear it. As a result, it seems to have very little effect on SYSENTER performance on my machine. There's another minor bug fix in here: it looks like the CFI annotations were wrong if CONFIG_AUDITSYSCALL=n. Testers beware: on Xen, SYSENTER with NT set turns into a GPF. I haven't touched anything on 32-bit kernels. The syscall mask change comes from a variant of this patch by Anish Bhatt. Note to stable maintainers: there is no known security issue here. A misguided program can set NT and cause the kernel to try and fail to deliver SIGSEGV, crashing the program. This patch fixes Far Cry on Wine: https://bugs.winehq.org/show_bug.cgi?id=33275 Reported-by: Anish Bhatt <anish@chelsio.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/395749a5d39a29bd3e4b35899cf3a3c1340e5595.1412189265.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14x86, flags: Rename X86_EFLAGS_BIT1 to X86_EFLAGS_FIXEDH. Peter Anvin
commit 1adfa76a95fe4444124a502f7cc858a39d5b8e01 upstream. Bit 1 in the x86 EFLAGS is always set. Name the macro something that actually tries to explain what it is all about, rather than being a tautology. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Gleb Natapov <gleb@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Link: http://lkml.kernel.org/n/tip-f10rx5vjjm6tfnt8o1wseb3v@git.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14x86, fpu: shift drop_init_fpu() from save_xstate_sig() to handle_signal()Oleg Nesterov
commit 66463db4fc5605d51c7bb81d009d5bf30a783a2c upstream. save_xstate_sig()->drop_init_fpu() doesn't look right. setup_rt_frame() can fail after that, in this case the next setup_rt_frame() triggered by SIGSEGV won't save fpu simply because the old state was lost. This obviously mean that fpu won't be restored after sys_rt_sigreturn() from SIGSEGV handler. Shift drop_init_fpu() into !failed branch in handle_signal(). Test-case (needs -O2): #include <stdio.h> #include <signal.h> #include <unistd.h> #include <sys/syscall.h> #include <sys/mman.h> #include <pthread.h> #include <assert.h> volatile double D; void test(double d) { int pid = getpid(); for (D = d; D == d; ) { /* sys_tkill(pid, SIGHUP); asm to avoid save/reload * fp regs around "C" call */ asm ("" : : "a"(200), "D"(pid), "S"(1)); asm ("syscall" : : : "ax"); } printf("ERR!!\n"); } void sigh(int sig) { } char altstack[4096 * 10] __attribute__((aligned(4096))); void *tfunc(void *arg) { for (;;) { mprotect(altstack, sizeof(altstack), PROT_READ); mprotect(altstack, sizeof(altstack), PROT_READ|PROT_WRITE); } } int main(void) { stack_t st = { .ss_sp = altstack, .ss_size = sizeof(altstack), .ss_flags = SS_ONSTACK, }; struct sigaction sa = { .sa_handler = sigh, }; pthread_t pt; sigaction(SIGSEGV, &sa, NULL); sigaltstack(&st, NULL); sa.sa_flags = SA_ONSTACK; sigaction(SIGHUP, &sa, NULL); pthread_create(&pt, NULL, tfunc, NULL); test(123.456); return 0; } Reported-by: Bean Anderson <bean@azulsystems.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Link: http://lkml.kernel.org/r/20140902175713.GA21646@redhat.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14x86, fpu: __restore_xstate_sig()->math_state_restore() needs preempt_disable()Oleg Nesterov
commit df24fb859a4e200d9324e2974229fbb7adf00aef upstream. Add preempt_disable() + preempt_enable() around math_state_restore() in __restore_xstate_sig(). Otherwise __switch_to() after __thread_fpu_begin() can overwrite fpu->state we are going to restore. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Link: http://lkml.kernel.org/r/20140902175717.GA21649@redhat.com Reviewed-by: Suresh Siddha <sbsiddha@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14x86: Reject x32 executables if x32 ABI not supportedBen Hutchings
commit 0e6d3112a4e95d55cf6dca88f298d5f4b8f29bd1 upstream. It is currently possible to execve() an x32 executable on an x86_64 kernel that has only ia32 compat enabled. However all its syscalls will fail, even _exit(). This usually causes it to segfault. Change the ELF compat architecture check so that x32 executables are rejected if we don't support the x32 ABI. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Link: http://lkml.kernel.org/r/1410120305.6822.9.camel@decadent.org.uk Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-30ARM: at91/PMC: don't forget to write PMC_PCDR register to disable clocksLudovic Desroches
commit cfa1950e6c6b72251e80adc736af3c3d2907ab0e upstream. When introducing support for sama5d3, the write to PMC_PCDR register has been accidentally removed. Reported-by: Nathalie Cyrille <nathalie.cyrille@atmel.com> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-30arm64: compat: fix compat types affecting struct compat_elf_prpsinfoVictor Kamensky
commit 971a5b6fe634bb7b617d8c5f25b6a3ddbc600194 upstream. The compat_elf_prpsinfo structure does not match the arch/arm struct elf_pspsinfo definition. As result NT_PRPSINFO note in core file created by arm64 kernel for aarch32 (compat) process has wrong size. So gdb cannot display command that caused process crash. Fix is to change size of __compat_uid_t, __compat_gid_t so it would match size of similar fields in arch/arm case. Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-30m68k: Disable/restore interrupts in hwreg_present()/hwreg_write()Geert Uytterhoeven
commit e4dc601bf99ccd1c95b7e6eef1d3cf3c4b0d4961 upstream. hwreg_present() and hwreg_write() temporarily change the VBR register to another vector table. This table contains a valid bus error handler only, all other entries point to arbitrary addresses. If an interrupt comes in while the temporary table is active, the processor will start executing at such an arbitrary address, and the kernel will crash. While most callers run early, before interrupts are enabled, or explicitly disable interrupts, Finn Thain pointed out that macsonic has one callsite that doesn't, causing intermittent boot crashes. There's another unsafe callsite in hilkbd. Fix this for good by disabling and restoring interrupts inside hwreg_present() and hwreg_write(). Explicitly disabling interrupts can be removed from the callsites later. Reported-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-30x86/intel/quark: Switch off CR4.PGE so TLB flush uses CR3 insteadBryan O'Donoghue
commit ee1b5b165c0a2f04d2107e634e51f05d0eb107de upstream. Quark x1000 advertises PGE via the standard CPUID method PGE bits exist in Quark X1000's PTEs. In order to flush an individual PTE it is necessary to reload CR3 irrespective of the PTE.PGE bit. See Quark Core_DevMan_001.pdf section 6.4.11 This bug was fixed in Galileo kernels, unfixed vanilla kernels are expected to crash and burn on this platform. Signed-off-by: Bryan O'Donoghue <pure.logic@nexus-software.ie> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/1411514784-14885-1-git-send-email-pure.logic@nexus-software.ie Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-30KVM: s390: unintended fallthrough for external callChristian Borntraeger
commit f346026e55f1efd3949a67ddd1dcea7c1b9a615e upstream. We must not fallthrough if the conditions for external call are not met. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-30kvm: x86: fix stale mmio cache bugDavid Matlack
commit 56f17dd3fbc44adcdbc3340fe3988ddb833a47a7 upstream. The following events can lead to an incorrect KVM_EXIT_MMIO bubbling up to userspace: (1) Guest accesses gpa X without a memory slot. The gfn is cached in struct kvm_vcpu_arch (mmio_gfn). On Intel EPT-enabled hosts, KVM sets the SPTE write-execute-noread so that future accesses cause EPT_MISCONFIGs. (2) Host userspace creates a memory slot via KVM_SET_USER_MEMORY_REGION covering the page just accessed. (3) Guest attempts to read or write to gpa X again. On Intel, this generates an EPT_MISCONFIG. The memory slot generation number that was incremented in (2) would normally take care of this but we fast path mmio faults through quickly_check_mmio_pf(), which only checks the per-vcpu mmio cache. Since we hit the cache, KVM passes a KVM_EXIT_MMIO up to userspace. This patch fixes the issue by using the memslot generation number to validate the mmio cache. Signed-off-by: David Matlack <dmatlack@google.com> [xiaoguangrong: adjust the code to make it simpler for stable-tree fix.] Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Reviewed-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Tested-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-05arm: multi_v7_defconfig: Enable Zynq UART driverSoren Brinkmann
commit 90de827b9c238f8d8209bc7adc70190575514315 upstream. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-05ARM: 7748/1: oabi: handle faults when loading swi instruction from userspaceWill Deacon
commit 1aa2b3b7a6c4f3dbd3671171113a20e6a6190e3b upstream. Running an OABI_COMPAT kernel on an SMP platform can lead to fun and games with page aging. If one CPU issues a swi instruction immediately before another CPU decides to mkold the page containing the swi instruction, then we will fault attempting to load the instruction during the vector_swi handler in order to retrieve its immediate field. Since this fault is not currently dealt with by our exception tables, this results in a panic: Unable to handle kernel paging request at virtual address 4020841c pgd = c490c000 [4020841c] *pgd=84451831, *pte=bf05859d, *ppte=00000000 Internal error: Oops: 17 [#1] PREEMPT SMP ARM Modules linked in: hid_sony(O) CPU: 1 Tainted: G W O (3.4.0-perf-gf496dca-01162-gcbcc62b #1) PC is at vector_swi+0x28/0x88 LR is at 0x40208420 This patch wraps all of the swi instruction loads with the USER macro and provides a shared exception table entry which simply rewinds the saved user PC and returns from the system call (without setting tbl, so there's no worries with tracing or syscall restarting). Returning to userspace will re-enter the page fault handler, from where we will probably send SIGSEGV to the current task. Reported-by: Wang, Yalin <yalin.wang@sonymobile.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Sheng Yong <shengyong1@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-05parisc: Only use -mfast-indirect-calls option for 32-bit kernel buildsJohn David Anglin
commit d26a7730b5874a5fa6779c62f4ad7c5065a94723 upstream. In spite of what the GCC manual says, the -mfast-indirect-calls has never been supported in the 64-bit parisc compiler. Indirect calls have always been done using function descriptors irrespective of the -mfast-indirect-calls option. Recently, it was noticed that a function descriptor was always requested when the -mfast-indirect-calls option was specified. This caused problems when the option was used in application code and doesn't make any sense because the whole point of the option is to avoid using a function descriptor for indirect calls. Fixing this broke 64-bit kernel builds. I will fix GCC but for now we need the attached change. This results in the same kernel code as before. Signed-off-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-05powerpc/perf: Fix ABIv2 kernel backtracesAnton Blanchard
commit 85101af13bb854a6572fa540df7c7201958624b9 upstream. ABIv2 kernels are failing to backtrace through the kernel. An example: 39.30% readseek2_proce [kernel.kallsyms] [k] find_get_entry | --- find_get_entry __GI___libc_read The problem is in valid_next_sp() where we check that the new stack pointer is at least STACK_FRAME_OVERHEAD below the previous one. ABIv1 has a minimum stack frame size of 112 bytes consisting of 48 bytes and 64 bytes of parameter save area. ABIv2 changes that to 32 bytes with no paramter save area. STACK_FRAME_OVERHEAD is in theory the minimum stack frame size, but we over 240 uses of it, some of which assume that it includes space for the parameter area. We need to work through all our stack defines and rationalise them but let's fix perf now by creating STACK_FRAME_MIN_SIZE and using in valid_next_sp(). This fixes the issue: 30.64% readseek2_proce [kernel.kallsyms] [k] find_get_entry | --- find_get_entry pagecache_get_page generic_file_read_iter new_sync_read vfs_read sys_read syscall_exit __GI___libc_read Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-05sched: Fix unreleased llc_shared_mask bit during CPU hotplugWanpeng Li
commit 03bd4e1f7265548832a76e7919a81f3137c44fd1 upstream. The following bug can be triggered by hot adding and removing a large number of xen domain0's vcpus repeatedly: BUG: unable to handle kernel NULL pointer dereference at 0000000000000004 IP: [..] find_busiest_group PGD 5a9d5067 PUD 13067 PMD 0 Oops: 0000 [#3] SMP [...] Call Trace: load_balance ? _raw_spin_unlock_irqrestore idle_balance __schedule schedule schedule_timeout ? lock_timer_base schedule_timeout_uninterruptible msleep lock_device_hotplug_sysfs online_store dev_attr_store sysfs_write_file vfs_write SyS_write system_call_fastpath Last level cache shared mask is built during CPU up and the build_sched_domain() routine takes advantage of it to setup the sched domain CPU topology. However, llc_shared_mask is not released during CPU disable, which leads to an invalid sched domainCPU topology. This patch fix it by releasing the llc_shared_mask correctly during CPU disable. Yasuaki also reported that this can happen on real hardware: https://lkml.org/lkml/2014/7/22/1018 His case is here: == Here is an example on my system. My system has 4 sockets and each socket has 15 cores and HT is enabled. In this case, each core of sockes is numbered as follows: | CPU# Socket#0 | 0-14 , 60-74 Socket#1 | 15-29, 75-89 Socket#2 | 30-44, 90-104 Socket#3 | 45-59, 105-119 Then llc_shared_mask of CPU#30 has 0x3fff80000001fffc0000000. It means that last level cache of Socket#2 is shared with CPU#30-44 and 90-104. When hot-removing socket#2 and #3, each core of sockets is numbered as follows: | CPU# Socket#0 | 0-14 , 60-74 Socket#1 | 15-29, 75-89 But llc_shared_mask is not cleared. So llc_shared_mask of CPU#30 remains having 0x3fff80000001fffc0000000. After that, when hot-adding socket#2 and #3, each core of sockets is numbered as follows: | CPU# Socket#0 | 0-14 , 60-74 Socket#1 | 15-29, 75-89 Socket#2 | 30-59 Socket#3 | 90-119 Then llc_shared_mask of CPU#30 becomes 0x3fff8000fffffffc0000000. It means that last level cache of Socket#2 is shared with CPU#30-59 and 90-104. So the mask has the wrong value. Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Tested-by: Linn Crosetto <linn@hp.com> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Toshi Kani <toshi.kani@hp.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Steven Rostedt <srostedt@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1411547885-48165-1-git-send-email-wanpeng.li@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-05x86 early_ioremap: Increase FIX_BTMAPS_SLOTS to 8Dave Young
commit 3eddc69ffeba092d288c386646bfa5ec0fce25fd upstream. 3.16 kernel boot fail with earlyprintk=efi, it keeps scrolling at the bottom line of screen. Bisected, the first bad commit is below: commit 86dfc6f339886559d80ee0d4bd20fe5ee90450f0 Author: Lv Zheng <lv.zheng@intel.com> Date: Fri Apr 4 12:38:57 2014 +0800 ACPICA: Tables: Fix table checksums verification before installation. I did some debugging by enabling both serial and efi earlyprintk, below is some debug dmesg, seems early_ioremap fails in scroll up function due to no free slot, see below dmesg output: WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:116 __early_ioremap+0x90/0x1c4() __early_ioremap(ed00c800, 00000c80) not found slot Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 3.17.0-rc1+ #204 Hardware name: Hewlett-Packard HP Z420 Workstation/1589, BIOS J61 v03.15 05/09/2013 Call Trace: dump_stack+0x4e/0x7a warn_slowpath_common+0x75/0x8e ? __early_ioremap+0x90/0x1c4 warn_slowpath_fmt+0x47/0x49 __early_ioremap+0x90/0x1c4 ? sprintf+0x46/0x48 early_ioremap+0x13/0x15 early_efi_map+0x24/0x26 early_efi_scroll_up+0x6d/0xc0 early_efi_write+0x1b0/0x214 call_console_drivers.constprop.21+0x73/0x7e console_unlock+0x151/0x3b2 ? vprintk_emit+0x49f/0x532 vprintk_emit+0x521/0x532 ? console_unlock+0x383/0x3b2 printk+0x4f/0x51 acpi_os_vprintf+0x2b/0x2d acpi_os_printf+0x43/0x45 acpi_info+0x5c/0x63 ? __acpi_map_table+0x13/0x18 ? acpi_os_map_iomem+0x21/0x147 acpi_tb_print_table_header+0x177/0x186 acpi_tb_install_table_with_override+0x4b/0x62 acpi_tb_install_standard_table+0xd9/0x215 ? early_ioremap+0x13/0x15 ? __acpi_map_table+0x13/0x18 acpi_tb_parse_root_table+0x16e/0x1b4 acpi_initialize_tables+0x57/0x59 acpi_table_init+0x50/0xce acpi_boot_table_init+0x1e/0x85 setup_arch+0x9b7/0xcc4 start_kernel+0x94/0x42d ? early_idt_handlers+0x120/0x120 x86_64_start_reservations+0x2a/0x2c x86_64_start_kernel+0xf3/0x100 Quote reply from Lv.zheng about the early ioremap slot usage in this case: """ In early_efi_scroll_up(), 2 mapping entries will be used for the src/dst screen buffer. In drivers/acpi/acpica/tbutils.c, we've improved the early table loading code in acpi_tb_parse_root_table(). We now need 2 mapping entries: 1. One mapping entry is used for RSDT table mapping. Each RSDT entry contains an address for another ACPI table. 2. For each entry in RSDP, we need another mapping entry to map the table to perform necessary check/override before installing it. When acpi_tb_parse_root_table() prints something through EFI earlyprintk console, we'll have 4 mapping entries used. The current 4 slots setting of early_ioremap() seems to be too small for such a use case. """ Thus increase the slot to 8 in this patch to fix this issue. boot-time mappings become 512 page with this patch. Signed-off-by: Dave Young <dyoung@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-05KVM: x86: handle idiv overflow at kvm_write_tscMarcelo Tosatti
commit 8915aa27d5efbb9185357175b0acf884325565f9 upstream. Its possible that idivl overflows (due to large delta stored in usdiff, valid scenario). Create an exception handler to catch the overflow exception (division by zero is protected by vcpu->arch.virtual_tsc_khz check), and interpret it accordingly (delta is larger than USEC_PER_SEC). Fixes https://bugzilla.redhat.com/show_bug.cgi?id=969644 Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Philipp Hahn <hahn@univention.de> Tested-by: Philipp Hahn <hahn@univention.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>