kernel/linux.git, branch v4.13.12

Linux 4.13.12

2017-11-08T09:17:19+00:00

irqchip/irq-mvebu-gicp: Add missing spin_lock init

2017-11-08T09:17:19+00:00

commit c9bb86338a6bb91e4d32db04feb6b8d423e04d06 upstream. A spin lock is used in the irq-mvebu-gicp driver, but it is never initialized. This patch adds the missing spin_lock_init() call in the driver's probe function. Fixes: a68a63cb4dfc ("irqchip/irq-mvebu-gicp: Add new driver for Marvell GICP") Signed-off-by: Antoine Tenart Signed-off-by: Thomas Gleixner Reviewed-by: gregory.clement@free-electrons.com Acked-by: marc.zyngier@arm.com Cc: thomas.petazzoni@free-electrons.com Cc: andrew@lunn.ch Cc: jason@lakedaemon.net Cc: nadavh@marvell.com Cc: miquel.raynal@free-electrons.com Cc: linux-arm-kernel@lists.infradead.org Cc: sebastian.hesselbarth@gmail.com Link: https://lkml.kernel.org/r/20171025072326.21030-1-antoine.tenart@free-electrons.com Signed-off-by: Greg Kroah-Hartman

x86/mcelog: Get rid of RCU remnants

2017-11-08T09:17:19+00:00

commit 7298f08ea8870d44d36c7d6cd07dd0303faef6c2 upstream. Jeremy reported a suspicious RCU usage warning in mcelog. /dev/mcelog is called in process context now as part of the notifier chain and doesn't need any of the fancy RCU and lockless accesses which it did in atomic context. Axe it all in favor of a simple mutex synchronization which cures the problem reported. Fixes: 5de97c9f6d85 ("x86/mce: Factor out and deprecate the /dev/mcelog driver") Reported-by: Jeremy Cline Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Reviewed-and-tested-by: Tony Luck Cc: Andi Kleen Cc: linux-edac@vger.kernel.org Cc: Laura Abbott Link: https://lkml.kernel.org/r/20171101164754.xzzmskl4ngrqc5br@pd.tnic Link: https://bugzilla.redhat.com/show_bug.cgi?id=1498969 Signed-off-by: Greg Kroah-Hartman

perf/cgroup: Fix perf cgroup hierarchy support

2017-11-08T09:17:19+00:00

commit be96b316deff35e119760982c43af74e606fa143 upstream. The following commit: 864c2357ca89 ("perf/core: Do not set cpuctx->cgrp for unscheduled cgroups") made list_update_cgroup_event() skip setting cpuctx->cgrp if no cgroup event targets %current's cgroup. This breaks perf_event's hierarchical support because events which target one of the ancestors get ignored. Fix it by using cgroup_is_descendant() test instead of equality. Signed-off-by: Tejun Heo Acked-by: Thomas Gleixner Cc: Arnaldo Carvalho de Melo Cc: David Carrillo-Cisneros Cc: Linus Torvalds Cc: Peter Zijlstra Cc: kernel-team@fb.com Fixes: 864c2357ca89 ("perf/core: Do not set cpuctx->cgrp for unscheduled cgroups") Link: http://lkml.kernel.org/r/20171028164237.GA972780@devbig577.frc2.facebook.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

futex: Fix more put_pi_state() vs. exit_pi_state_list() races

2017-11-08T09:17:19+00:00

commit 153fbd1226fb30b8630802aa5047b8af5ef53c9f upstream. Dmitry (through syzbot) reported being able to trigger the WARN in get_pi_state() and a use-after-free on: raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock); Both are due to this race: exit_pi_state_list() put_pi_state() lock(&curr->pi_lock) while() { pi_state = list_first_entry(head); hb = hash_futex(&pi_state->key); unlock(&curr->pi_lock); dec_and_test(&pi_state->refcount); lock(&hb->lock) lock(&pi_state->pi_mutex.wait_lock) // uaf if pi_state free'd lock(&curr->pi_lock); .... unlock(&curr->pi_lock); get_pi_state(); // WARN; refcount==0 The problem is we take the reference count too late, and don't allow it being 0. Fix it by using inc_not_zero() and simply retrying the loop when we fail to get a refcount. In that case put_pi_state() should remove the entry from the list. Reported-by: Dmitry Vyukov Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Thomas Gleixner Cc: Gratian Crisan Cc: Linus Torvalds Cc: Peter Zijlstra Cc: dvhart@infradead.org Cc: syzbot Cc: syzkaller-bugs@googlegroups.com Fixes: c74aef2d06a9 ("futex: Fix pi_state->owner serialization") Link: http://lkml.kernel.org/r/20171031101853.xpfh72y643kdfhjs@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

powerpc/kprobes: Dereference function pointers only if the address does not belong to kernel text

2017-11-08T09:17:19+00:00

commit e6c4dcb308160115287afd87afb63b5684d75a5b upstream. This makes the changes introduced in commit 83e840c770f2c5 ("powerpc64/elfv1: Only dereference function descriptor for non-text symbols") to be specific to the kprobe subsystem. We previously changed ppc_function_entry() to always check the provided address to confirm if it needed to be dereferenced. This is actually only an issue for kprobe blacklisted asm labels (through use of _ASM_NOKPROBE_SYMBOL) and can cause other issues with ftrace. Also, the additional checks are not really necessary for our other uses. As such, move this check to the kprobes subsystem. Fixes: 83e840c770f2 ("powerpc64/elfv1: Only dereference function descriptor for non-text symbols") Signed-off-by: Naveen N. Rao Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

x86: CPU: Fix up "cpu MHz" in /proc/cpuinfo

2017-11-08T09:17:19+00:00

commit 941f5f0f6ef5338814145cf2b813cf1f98873e2f upstream. Commit 890da9cf0983 (Revert "x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz"") is not sufficient to restore the previous behavior of "cpu MHz" in /proc/cpuinfo on x86 due to some changes made after the commit it has reverted. To address this, make the code in question use arch_freq_get_on_cpu() which also is used by cpufreq for reporting the current frequency of CPUs and since that function doesn't really depend on cpufreq in any way, drop the CONFIG_CPU_FREQ dependency for the object file containing it. Also refactor arch_freq_get_on_cpu() somewhat to avoid IPIs and return cached values right away if it is called very often over a short time (to prevent user space from triggering IPI storms through it). Fixes: 890da9cf0983 (Revert "x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz"") Signed-off-by: Rafael J. Wysocki Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

Revert "x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz""

2017-11-08T09:17:19+00:00

commit 890da9cf098364b11a7f7f5c22fa652531624d03 upstream. This reverts commit 51204e0639c49ada02fd823782ad673b6326d748. There wasn't really any good reason for it, and people are complaining (rightly) that it broke existing practice. Cc: Len Brown Cc: Thomas Gleixner Cc: Rafael J. Wysocki Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

MIPS: SMP: Fix deadlock & online race

2017-11-08T09:17:19+00:00

commit 9e8c399a88f0b87e41a894911475ed2a8f8dff9e upstream. Commit 6f542ebeaee0 ("MIPS: Fix race on setting and getting cpu_online_mask") effectively reverted commit 8f46cca1e6c06 ("MIPS: SMP: Fix possibility of deadlock when bringing CPUs online") and thus has reinstated the possibility of deadlock. The commit was based on testing of kernel v4.4, where the CPU hotplug core code issued a BUG() if the starting CPU is not marked online when the boot CPU returns from __cpu_up. The commit fixes this race (in v4.4), but re-introduces the deadlock situation. As noted in the commit message, upstream differs in this area. Commit 8df3e07e7f21f ("cpu/hotplug: Let upcoming cpu bring itself fully up") adds a completion event in the CPU hotplug core code, making this race impossible. However, people were unhappy with relying on the core code to do the right thing. To address the issues both commits were trying to fix, add a second completion event in the MIPS smp hotplug path. It removes the possibility of a race, since the MIPS smp hotplug code now synchronises both the boot and secondary CPUs before they return to the hotplug core code. It also addresses the deadlock by ensuring that the secondary CPU is not marked online before it's counters are synchronised. This fix should also be backported to fix the race condition introduced by the backport of commit 8f46cca1e6c06 ("MIPS: SMP: Fix possibility of deadlock when bringing CPUs online"), through really that race only existed before commit 8df3e07e7f21f ("cpu/hotplug: Let upcoming cpu bring itself fully up"). Signed-off-by: Matt Redfearn Fixes: 6f542ebeaee0 ("MIPS: Fix race on setting and getting cpu_online_mask") CC: Matija Glavinic Pecotic Patchwork: https://patchwork.linux-mips.org/patch/17376/ Signed-off-by: James Hogan Signed-off-by: Greg Kroah-Hartman

MIPS: microMIPS: Fix incorrect mask in insn_table_MM

2017-11-08T09:17:18+00:00

commit 77238e76b9156d28d86c1e31c00ed2960df0e4de upstream. It seems that this is a typo error and the proper bit masking is "RT | RS" instead of "RS | RS". This issue was detected with the help of Coccinelle. Fixes: d6b3314b49e1 ("MIPS: uasm: Add lh uam instruction") Reported-by: Julia Lawall Signed-off-by: Gustavo A. R. Silva Reviewed-by: James Hogan Patchwork: https://patchwork.linux-mips.org/patch/17551/ Signed-off-by: James Hogan Signed-off-by: Greg Kroah-Hartman