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* Linux 4.13-rc6v4.13-rc6Linus Torvalds2017-08-201-1/+1
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* Sanitize 'move_pages()' permission checksLinus Torvalds2017-08-201-8/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The 'move_paghes()' system call was introduced long long ago with the same permission checks as for sending a signal (except using CAP_SYS_NICE instead of CAP_SYS_KILL for the overriding capability). That turns out to not be a great choice - while the system call really only moves physical page allocations around (and you need other capabilities to do a lot of it), you can check the return value to map out some the virtual address choices and defeat ASLR of a binary that still shares your uid. So change the access checks to the more common 'ptrace_may_access()' model instead. This tightens the access checks for the uid, and also effectively changes the CAP_SYS_NICE check to CAP_SYS_PTRACE, but it's unlikely that anybody really _uses_ this legacy system call any more (we hav ebetter NUMA placement models these days), so I expect nobody to notice. Famous last words. Reported-by: Otto Ebeling <otto.ebeling@iki.fi> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Willy Tarreau <w@1wt.eu> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2017-08-2019-68/+85
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "Another pile of small fixes and updates for x86: - Plug a hole in the SMAP implementation which misses to clear AC on NMI entry - Fix the norandmaps/ADDR_NO_RANDOMIZE logic so the command line parameter works correctly again - Use the proper accessor in the startup64 code for next_early_pgt to prevent accessing of invalid addresses and faulting in the early boot code. - Prevent CPU hotplug lock recursion in the MTRR code - Unbreak CPU0 hotplugging - Rename overly long CPUID bits which got introduced in this cycle - Two commits which mark data 'const' and restrict the scope of data and functions to file scope by making them 'static'" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Constify attribute_group structures x86/boot/64/clang: Use fixup_pointer() to access 'next_early_pgt' x86/elf: Remove the unnecessary ADDR_NO_RANDOMIZE checks x86: Fix norandmaps/ADDR_NO_RANDOMIZE x86/mtrr: Prevent CPU hotplug lock recursion x86: Mark various structures and functions as 'static' x86/cpufeature, kvm/svm: Rename (shorten) the new "virtualized VMSAVE/VMLOAD" CPUID flag x86/smpboot: Unbreak CPU0 hotplug x86/asm/64: Clear AC on NMI entries
| * x86: Constify attribute_group structuresArvind Yadav2017-08-187-36/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | attribute_groups are not supposed to change at runtime and none of the groups is modified. Mark the non-const structs as const. [ tglx: Folded into one big patch ] Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: tony.luck@intel.com Cc: bp@alien8.de Link: http://lkml.kernel.org/r/1500550238-15655-2-git-send-email-arvind.yadav.cs@gmail.com
| * x86/boot/64/clang: Use fixup_pointer() to access 'next_early_pgt'Alexander Potapenko2017-08-171-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __startup_64() is normally using fixup_pointer() to access globals in a position-independent fashion. However 'next_early_pgt' was accessed directly, which wasn't guaranteed to work. Luckily GCC was generating a R_X86_64_PC32 PC-relative relocation for 'next_early_pgt', but Clang emitted a R_X86_64_32S, which led to accessing invalid memory and rebooting the kernel. Signed-off-by: Alexander Potapenko <glider@google.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Davidson <md@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: c88d71508e36 ("x86/boot/64: Rewrite startup_64() in C") Link: http://lkml.kernel.org/r/20170816190808.131748-1-glider@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * x86/elf: Remove the unnecessary ADDR_NO_RANDOMIZE checksOleg Nesterov2017-08-162-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ADDR_NO_RANDOMIZE checks in stack_maxrandom_size() and randomize_stack_top() are not required. PF_RANDOMIZE is set by load_elf_binary() only if ADDR_NO_RANDOMIZE is not set, no need to re-check after that. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Dmitry Safonov <dsafonov@virtuozzo.com> Cc: stable@vger.kernel.org Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Link: http://lkml.kernel.org/r/20170815154011.GB1076@redhat.com
| * x86: Fix norandmaps/ADDR_NO_RANDOMIZEOleg Nesterov2017-08-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Documentation/admin-guide/kernel-parameters.txt says: norandmaps Don't use address space randomization. Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space but it doesn't work because arch_rnd() which is used to randomize mm->mmap_base returns a random value unconditionally. And as Kirill pointed out, ADDR_NO_RANDOMIZE is broken by the same reason. Just shift the PF_RANDOMIZE check from arch_mmap_rnd() to arch_rnd(). Fixes: 1b028f784e8c ("x86/mm: Introduce mmap_compat_base() for 32-bit mmap()") Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Cyrill Gorcunov <gorcunov@openvz.org> Reviewed-by: Dmitry Safonov <dsafonov@virtuozzo.com> Cc: stable@vger.kernel.org Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20170815153952.GA1076@redhat.com
| * x86/mtrr: Prevent CPU hotplug lock recursionThomas Gleixner2017-08-151-3/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Larry reported a CPU hotplug lock recursion in the MTRR code. ============================================ WARNING: possible recursive locking detected systemd-udevd/153 is trying to acquire lock: (cpu_hotplug_lock.rw_sem){.+.+.+}, at: [<c030fc26>] stop_machine+0x16/0x30 but task is already holding lock: (cpu_hotplug_lock.rw_sem){.+.+.+}, at: [<c0234353>] mtrr_add_page+0x83/0x470 .... cpus_read_lock+0x48/0x90 stop_machine+0x16/0x30 mtrr_add_page+0x18b/0x470 mtrr_add+0x3e/0x70 mtrr_add_page() holds the hotplug rwsem already and calls stop_machine() which acquires it again. Call stop_machine_cpuslocked() instead. Reported-and-tested-by: Larry Finger <Larry.Finger@lwfinger.net> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1708140920250.1865@nanos Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Borislav Petkov <bp@suse.de>
| * x86: Mark various structures and functions as 'static'Colin Ian King2017-08-114-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mark a couple of structures and functions as 'static', pointed out by Sparse: warning: symbol 'bts_pmu' was not declared. Should it be static? warning: symbol 'p4_event_aliases' was not declared. Should it be static? warning: symbol 'rapl_attr_groups' was not declared. Should it be static? symbol 'process_uv2_message' was not declared. Should it be static? Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Andrew Banman <abanman@hpe.com> # for the UV change Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: kernel-janitors@vger.kernel.org Link: http://lkml.kernel.org/r/20170810155709.7094-1-colin.king@canonical.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * x86/cpufeature, kvm/svm: Rename (shorten) the new "virtualized ↵Borislav Petkov2017-08-112-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | VMSAVE/VMLOAD" CPUID flag "virtual_vmload_vmsave" is what is going to land in /proc/cpuinfo now as per v4.13-rc4, for a single feature bit which is clearly too long. So rename it to what it is called in the processor manual. "v_vmsave_vmload" is a bit shorter, after all. We could go more aggressively here but having it the same as in the processor manual is advantageous. Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Radim Krčmář <rkrcmar@redhat.com> Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com> Cc: Jörg Rödel <joro@8bytes.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm-ML <kvm@vger.kernel.org> Link: http://lkml.kernel.org/r/20170801185552.GA3743@nazgul.tnic Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * x86/smpboot: Unbreak CPU0 hotplugVitaly Kuznetsov2017-08-101-13/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A hang on CPU0 onlining after a preceding offlining is observed. Trace shows that CPU0 is stuck in check_tsc_sync_target() waiting for source CPU to run check_tsc_sync_source() but this never happens. Source CPU, in its turn, is stuck on synchronize_sched() which is called from native_cpu_up() -> do_boot_cpu() -> unregister_nmi_handler(). So it's a classic ABBA deadlock, due to the use of synchronize_sched() in unregister_nmi_handler(). Fix the bug by moving unregister_nmi_handler() from do_boot_cpu() to native_cpu_up() after cpu onlining is done. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170803105818.9934-1-vkuznets@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * x86/asm/64: Clear AC on NMI entriesAndy Lutomirski2017-08-101-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This closes a hole in our SMAP implementation. This patch comes from grsecurity. Good catch! Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/314cc9f294e8f14ed85485727556ad4f15bb1659.1502159503.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2017-08-205-11/+12
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "A few small fixes for timer drivers: - Prevent infinite recursion in the arm architected timer driver with ftrace - Propagate error codes to the caller in case of failure in EM STI driver - Adjust a bogus loop iteration in the arm architected timer driver - Add a missing Kconfig dependency to the pistachio clocksource to prevent build failures - Correctly check for IS_ERR() instead of NULL in the shared timer-of code" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource/drivers/arm_arch_timer: Avoid infinite recursion when ftrace is enabled clocksource/drivers/Kconfig: Fix CLKSRC_PISTACHIO dependencies clocksource/drivers/timer-of: Checking for IS_ERR() instead of NULL clocksource/drivers/em_sti: Fix error return codes in em_sti_probe() clocksource/drivers/arm_arch_timer: Fix mem frame loop initialization
| * \ Merge branch 'clockevents/4.13-fixes' of ↵Ingo Molnar2017-08-135-11/+12
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | http://git.linaro.org/people/daniel.lezcano/linux into timers/urgent Pull clockevents fixes from Daniel Lezcano: " - Fix error check against IS_ERR() instead of NULL for the timer-of code (Dan Carpenter) - Fix infinite recusion with ftrace for the ARM architected timer (Ding Tianhong) - Fix the error code return in the em_sti's probe function (Gustavo A. R. Silva) - Fix Kconfig dependency for the pistachio driver (Matt Redfearn) - Fix mem frame loop initialization for the ARM architected timer (Matthias Kaehlcke)" Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | clocksource/drivers/arm_arch_timer: Avoid infinite recursion when ftrace is ↵Ding Tianhong2017-08-111-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | enabled On platforms with an arch timer erratum workaround, it's possible for arch_timer_reg_read_stable() to recurse into itself when certain tracing options are enabled, leading to stack overflows and related problems. For example, when PREEMPT_TRACER and FUNCTION_GRAPH_TRACER are selected, it's possible to trigger this with: $ mount -t debugfs nodev /sys/kernel/debug/ $ echo function_graph > /sys/kernel/debug/tracing/current_tracer The problem is that in such cases, preempt_disable() instrumentation attempts to acquire a timestamp via trace_clock(), resulting in a call back to arch_timer_reg_read_stable(), and hence recursion. This patch changes arch_timer_reg_read_stable() to use preempt_{disable,enable}_notrace(), which avoids this. This problem is similar to the fixed by upstream commit 96b3d28bf4 ("sched/clock: Prevent tracing recursion in sched_clock_cpu()"). Fixes: 6acc71ccac71 ("arm64: arch_timer: Allows a CPU-specific erratum to only affect a subset of CPUs") Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
| | * | clocksource/drivers/Kconfig: Fix CLKSRC_PISTACHIO dependenciesMatt Redfearn2017-08-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In v4.13, CLKSRC_PISTACHIO can select TIMER_OF on architectures without GENERIC_CLOCKEVENTS, resulting in a struct clock_event_device missing some required features and build breakage compiling timer_of.c. One of the symbols selecting TIMER_OF is CLKSRC_PISTACHIO, so add the dependency on GENERIC_CLOCKEVENTS. Thanks to kbuild test robot for finding this error (https://lkml.org/lkml/2017/7/16/249) Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Suggested-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
| | * | clocksource/drivers/timer-of: Checking for IS_ERR() instead of NULLDan Carpenter2017-08-111-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current code checks the return value of the of_io_request_and_map() function as it was returning a NULL pointer in case of error. However, it returns an error code encoded in the pointer return value, not a NULL value. Fix this by checking the returned pointer against IS_ERR() and return the error with PTR_ERR(). Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
| | * | clocksource/drivers/em_sti: Fix error return codes in em_sti_probe()Gustavo A. R. Silva2017-08-101-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Propagate the return values of platform_get_irq and devm_request_irq on failure. Cc: Frans Klaver <fransklaver@gmail.com> Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
| | * | clocksource/drivers/arm_arch_timer: Fix mem frame loop initializationMatthias Kaehlcke2017-08-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The loop to find the best memory frame in arch_timer_mem_acpi_init() initializes the loop counter with itself ('i = i'), which is suspicious in the first place and pointed out by clang. The loop condition is 'i < timer_count' and a prior for loop exits when 'i' reaches 'timer_count', therefore the second loop is never executed. Initialize the loop counter with 0 to iterate over all timers, which supposedly was the intention before the typo monster attacked. Fixes: c2743a36765d3 ("clocksource: arm_arch_timer: add GTDT support for memory-mapped timer") Signed-off-by: Matthias Kaehlcke <mka@chromium.org> Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
* | | | Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2017-08-203-19/+48
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "Two fixes for the perf subsystem: - Fix an inconsistency of RDPMC mm struct tagging across exec() which causes RDPMC to fault. - Correct the timestamp mechanics across IOC_DISABLE/ENABLE which causes incorrect timestamps and total time calculations" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Fix time on IOC_ENABLE perf/x86: Fix RDPMC vs. mm_struct tracking
| * | | | perf/core: Fix time on IOC_ENABLEPeter Zijlstra2017-08-101-5/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Vince reported that when we do IOC_ENABLE/IOC_DISABLE while the task is SIGSTOP'ed state the timestamps go wobbly. It turns out we indeed fail to correctly account time while in 'OFF' state and doing IOC_ENABLE without getting scheduled in exposes the problem. Further thinking about this problem, it occurred to me that we can suffer a similar fate when we migrate an uncore event between CPUs. The perf_event_install() on the 'new' CPU will do add_event_to_ctx() which will reset all the time stamp, resulting in a subsequent update_event_times() to overwrite the total_time_* fields with smaller values. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | perf/x86: Fix RDPMC vs. mm_struct trackingPeter Zijlstra2017-08-103-14/+12
| | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Vince reported the following rdpmc() testcase failure: > Failing test case: > > fd=perf_event_open(); > addr=mmap(fd); > exec() // without closing or unmapping the event > fd=perf_event_open(); > addr=mmap(fd); > rdpmc() // GPFs due to rdpmc being disabled The problem is of course that exec() plays tricks with what is current->mm, only destroying the old mappings after having installed the new mm. Fix this confusion by passing along vma->vm_mm instead of relying on current->mm. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Tested-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Fixes: 1e0fb9ec679c ("perf: Add pmu callbacks to track event mapping and unmapping") Link: http://lkml.kernel.org/r/20170802173930.cstykcqefmqt7jau@hirez.programming.kicks-ass.net [ Minor cleanups. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds2017-08-2012-38/+84
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: "A pile of smallish changes all over the place: - Add a missing ISB in the GIC V1 driver - Remove an ACPI version check in the GIC V3 ITS driver - Add the missing irq_pm_shutdown function for BRCMSTB-L2 to avoid spurious wakeups - Remove the artifical limitation of ITS instances to the number of NUMA nodes which prevents utilizing the ITS hardware correctly - Prevent a infinite parsing loop in the GIC-V3 ITS/MSI code - Honour the force affinity argument in the GIC-V3 driver which is required to make perf work correctly - Correctly report allocation failures in GIC-V2/V3 to avoid using half allocated and initialized interrupts. - Fixup checks against nr_cpu_ids in the generic IPI code" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq/ipi: Fixup checks against nr_cpu_ids genirq: Restore trigger settings in irq_modify_status() MAINTAINERS: Remove Jason Cooper's irqchip git tree irqchip/gic-v3-its-platform-msi: Fix msi-parent parsing loop irqchip/gic-v3-its: Allow GIC ITS number more than MAX_NUMNODES irqchip: brcmstb-l2: Define an irq_pm_shutdown function irqchip/gic: Ensure we have an ISB between ack and ->handle_irq irqchip/gic-v3-its: Remove ACPICA version check for ACPI NUMA irqchip/gic-v3: Honor forced affinity setting irqchip/gic-v3: Report failures in gic_irq_domain_alloc irqchip/gic-v2: Report failures in gic_irq_domain_alloc irqchip/atmel-aic: Remove root argument from ->fixup() prototype irqchip/atmel-aic: Fix unbalanced refcount in aic_common_rtc_irq_fixup() irqchip/atmel-aic: Fix unbalanced of_node_put() in aic_common_irq_fixup()
| * | | | genirq/ipi: Fixup checks against nr_cpu_idsAlexey Dobriyan2017-08-201-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Valid CPU ids are [0, nr_cpu_ids-1] inclusive. Fixes: 3b8e29a82dd1 ("genirq: Implement ipi_send_mask/single()") Fixes: f9bce791ae2a ("genirq: Add a new function to get IPI reverse mapping") Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170819095751.GB27864@avx2
| * | | | genirq: Restore trigger settings in irq_modify_status()Marc Zyngier2017-08-181-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | irq_modify_status starts by clearing the trigger settings from irq_data before applying the new settings, but doesn't restore them, leaving them to IRQ_TYPE_NONE. That's pretty confusing to the potential request_irq() that could follow. Instead, snapshot the settings before clearing them, and restore them if the irq_modify_status() invocation was not changing the trigger. Fixes: 1e2a7d78499e ("irqdomain: Don't set type when mapping an IRQ") Reported-and-tested-by: jeffy <jeffy.chen@rock-chips.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jon Hunter <jonathanh@nvidia.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170818095345.12378-1-marc.zyngier@arm.com
| * | | | MAINTAINERS: Remove Jason Cooper's irqchip git treeFlorian Fainelli2017-08-181-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Jason's irqchip tree does not seem to have been updated for many months now, remove it from the list of trees to avoid any possible confusion. Jason says: "Unfortunately, when I have time for irqchip, I don't always have the time to properly follow up with pull-requests. So, for the time being, I'll stick to reviewing as I can." Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Jason Cooper <jason@lakedaemon.net> Cc: marc.zyngier@arm.com Link: http://lkml.kernel.org/r/20170727224733.8288-1-f.fainelli@gmail.com
| * | | | Merge tag 'irqchip-4.13-3' of ↵Thomas Gleixner2017-08-149-33/+74
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent Pull irqchip fixes for 4.13 from Marc Zyngier Mostly GIC related, again: - GICv3 ITS NUMA handling fixes - GICv3 force affinity handling - Barrier adjustment in both GIC interrupt handling - Error reporting when the DT presents an incompatible interrupt - GICv3 platform MSI DT parsing bug fix - Broadcom L2 PM fix - Atmel AIC cleanups
| | * | | | irqchip/gic-v3-its-platform-msi: Fix msi-parent parsing loopLorenzo Pieralisi2017-08-101-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While parsing the msi-parent property to chase up the IRQ domain a given device belongs to, the index into the msi-parent tuple should be incremented to ensure all properties entries are taken into account. Current code missed the index update so the parsing loop does not work in case multiple msi-parent phandles are present and may turn into an infinite loop in of_pmsi_get_dev_id() if phandle at index 0 does not correspond to the domain we are actually looking-up. Fix the code by updating the phandle index at each iteration in of_pmsi_get_dev_id(). Fixes: deac7fc1c87f ("irqchip/gic-v3-its: Parse new version of msi-parent property") Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | | irqchip/gic-v3-its: Allow GIC ITS number more than MAX_NUMNODESHanjun Guo2017-08-101-7/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When enabling ITS NUMA support on D05, I got the boot log: [ 0.000000] SRAT: PXM 0 -> ITS 0 -> Node 0 [ 0.000000] SRAT: PXM 0 -> ITS 1 -> Node 0 [ 0.000000] SRAT: PXM 0 -> ITS 2 -> Node 0 [ 0.000000] SRAT: PXM 1 -> ITS 3 -> Node 1 [ 0.000000] SRAT: ITS affinity exceeding max count[4] This is wrong on D05 as we have 8 ITSs with 4 NUMA nodes. So dynamically alloc the memory needed instead of using its_srat_maps[MAX_NUMNODES], which count the number of ITS entry(ies) in SRAT and alloc its_srat_maps as needed, then build the mapping of numa node to ITS ID. Of course, its_srat_maps will be freed after ITS probing because we don't need that after boot. After doing this, I got what I wanted: [ 0.000000] SRAT: PXM 0 -> ITS 0 -> Node 0 [ 0.000000] SRAT: PXM 0 -> ITS 1 -> Node 0 [ 0.000000] SRAT: PXM 0 -> ITS 2 -> Node 0 [ 0.000000] SRAT: PXM 1 -> ITS 3 -> Node 1 [ 0.000000] SRAT: PXM 2 -> ITS 4 -> Node 2 [ 0.000000] SRAT: PXM 2 -> ITS 5 -> Node 2 [ 0.000000] SRAT: PXM 2 -> ITS 6 -> Node 2 [ 0.000000] SRAT: PXM 3 -> ITS 7 -> Node 3 Fixes: dbd2b8267233 ("irqchip/gic-v3-its: Add ACPI NUMA node mapping") Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com> Cc: John Garry <john.garry@huawei.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | | irqchip: brcmstb-l2: Define an irq_pm_shutdown functionFlorian Fainelli2017-08-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Broadcom STB platforms support S5 and we allow specific hardware wake-up events to take us out of this state. Because we were not defining an irq_pm_shutdown() function pointer, we would not be correctly masking non-wakeup events, which would result in spurious wake-ups from sources that were not explicitly configured for wake-up. Fixes: 7f646e92766e ("irqchip: brcmstb-l2: Add Broadcom Set Top Box Level-2 interrupt controller") Acked-by: Gregory Fong <gregory.0xf0@gmail.com> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | | irqchip/gic: Ensure we have an ISB between ack and ->handle_irqWill Deacon2017-08-022-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Devices that expose their interrupt status registers via system registers (e.g. Statistical profiling, CPU PMU, DynamIQ PMU, arch timer, vgic (although unused by Linux), ...) rely on a context synchronising operation on the CPU to ensure that the updated status register is visible to the CPU when handling the interrupt. This usually happens as a result of taking the IRQ exception in the first place, but there are two race scenarios where this isn't the case. For example, let's say we have two peripherals (X and Y), where Y uses a system register for its interrupt status. Case 1: 1. CPU takes an IRQ exception as a result of X raising an interrupt 2. Y then raises its interrupt line, but the update to its system register is not yet visible to the CPU 3. The GIC decides to expose Y's interrupt number first in the Ack register 4. The CPU runs the IRQ handler for Y, but the status register is stale Case 2: 1. CPU takes an IRQ exception as a result of X raising an interrupt 2. CPU reads the interrupt number for X from the Ack register and runs its IRQ handler 3. Y raises its interrupt line and the Ack register is updated, but again, the update to its system register is not yet visible to the CPU. 4. Since the GIC drivers poll the Ack register, we read Y's interrupt number and run its handler without a context synchronisation operation, therefore seeing the stale register value. In either case, we run the risk of missing an IRQ. This patch solves the problem by ensuring that we execute an ISB in the GIC drivers prior to invoking the interrupt handler. This is already the case for GICv3 and EOIMode 1 (the usual case for the host). Cc: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | | irqchip/gic-v3-its: Remove ACPICA version check for ACPI NUMARobert Richter2017-08-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The version check was added due to dependency to a618c7f89a02 ACPICA: Add support for new SRAT subtable Now, that this code is in the kernel, remove the check. This is esp. useful to enable backports. Signed-off-by: Robert Richter <rrichter@cavium.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | | irqchip/gic-v3: Honor forced affinity settingSuzuki K Poulose2017-07-041-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Honor the 'force' flag for set_affinity, by selecting a CPU from the given mask (which may not be reported "online" by the cpu_online_mask). Some drivers, like ARM PMU, rely on it. Cc: Marc Zyngier <marc.zyngier@arm.com> Reported-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | | irqchip/gic-v3: Report failures in gic_irq_domain_allocSuzuki K Poulose2017-07-041-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the GIC cannot map an IRQ via irq_domain_ops->alloc(), it doesn't return an error code. This can cause a problem with drivers, where it thinks it has successfully got an IRQ for the device, but requesting the same ends up failure with -ENOSYS (as the IRQ's chip is not set). Fixes: commit 443acc4f37f6 ("irqchip: GICv3: Convert to domain hierarchy") Cc: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | | irqchip/gic-v2: Report failures in gic_irq_domain_allocSuzuki K Poulose2017-07-041-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the GIC cannot map an IRQ via irq_domain_ops->alloc(), it doesn't return an error code. This can cause a problem with drivers, where it thinks it has successfully got an IRQ for the device, but requesting the same ends up failure with -ENOSYS (as the IRQ's chip is not set). Fixes: commit 9a1091ef0017c ("irqchip: gic: Support hierarchy irq domain.") Cc: Yingjoe Chen <yingjoe.chen@mediatek.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | | irqchip/atmel-aic: Remove root argument from ->fixup() prototypeBoris Brezillon2017-07-044-15/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are no longer using the root argument passed to the ->fixup() hooks. Remove it. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | | irqchip/atmel-aic: Fix unbalanced refcount in aic_common_rtc_irq_fixup()Boris Brezillon2017-07-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | of_find_compatible_node() is calling of_node_put() on its first argument thus leading to an unbalanced of_node_get/put() issue if the node has not been retained before that. Instead of passing the root node, pass NULL, which does exactly the same: iterate over all DT nodes, starting from the root node. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Reported-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Fixes: 3d61467f9bab ("irqchip: atmel-aic: Implement RTC irq fixup") Cc: <stable@vger.kernel.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | | irqchip/atmel-aic: Fix unbalanced of_node_put() in aic_common_irq_fixup()Boris Brezillon2017-07-041-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | aic_common_irq_fixup() is calling twice of_node_put() on the same node thus leading to an unbalanced refcount on the root node. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Reported-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Fixes: b2f579b58e93 ("irqchip: atmel-aic: Add irq fixup infrastructure") Cc: <stable@vger.kernel.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* | | | | | Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds2017-08-205-0/+76
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull watchdog fix from Thomas Gleixner: "A fix for the hardlockup watchdog to prevent false positives with extreme Turbo-Modes which make the perf/NMI watchdog fire faster than the hrtimer which is used to verify. Slightly larger than the minimal fix, which just would increase the hrtimer frequency, but comes with extra overhead of more watchdog timer interrupts and thread wakeups for all users. With this change we restrict the overhead to the extreme Turbo-Mode systems" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kernel/watchdog: Prevent false positives with turbo modes
| * | | | | | kernel/watchdog: Prevent false positives with turbo modesThomas Gleixner2017-08-185-0/+76
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hardlockup detector on x86 uses a performance counter based on unhalted CPU cycles and a periodic hrtimer. The hrtimer period is about 2/5 of the performance counter period, so the hrtimer should fire 2-3 times before the performance counter NMI fires. The NMI code checks whether the hrtimer fired since the last invocation. If not, it assumess a hard lockup. The calculation of those periods is based on the nominal CPU frequency. Turbo modes increase the CPU clock frequency and therefore shorten the period of the perf/NMI watchdog. With extreme Turbo-modes (3x nominal frequency) the perf/NMI period is shorter than the hrtimer period which leads to false positives. A simple fix would be to shorten the hrtimer period, but that comes with the side effect of more frequent hrtimer and softlockup thread wakeups, which is not desired. Implement a low pass filter, which checks the perf/NMI period against kernel time. If the perf/NMI fires before 4/5 of the watchdog period has elapsed then the event is ignored and postponed to the next perf/NMI. That solves the problem and avoids the overhead of shorter hrtimer periods and more frequent softlockup thread wakeups. Fixes: 58687acba592 ("lockup_detector: Combine nmi_watchdog and softlockup detector") Reported-and-tested-by: Kan Liang <Kan.liang@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: dzickus@redhat.com Cc: prarit@redhat.com Cc: ak@linux.intel.com Cc: babu.moger@oracle.com Cc: peterz@infradead.org Cc: eranian@google.com Cc: acme@redhat.com Cc: stable@vger.kernel.org Cc: atomlin@redhat.com Cc: akpm@linux-foundation.org Cc: torvalds@linux-foundation.org Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1708150931310.1886@nanos
* | | | | | | Merge branch 'akpm' (patches from Andrew)Linus Torvalds2017-08-1822-103/+224
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge misc fixes from Andrew Morton: "14 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mm: revert x86_64 and arm64 ELF_ET_DYN_BASE base changes mm/vmalloc.c: don't unconditonally use __GFP_HIGHMEM mm/mempolicy: fix use after free when calling get_mempolicy mm/cma_debug.c: fix stack corruption due to sprintf usage signal: don't remove SIGNAL_UNKILLABLE for traced tasks. mm, oom: fix potential data corruption when oom_reaper races with writer mm: fix double mmap_sem unlock on MMF_UNSTABLE enforced SIGBUS slub: fix per memcg cache leak on css offline mm: discard memblock data later test_kmod: fix description for -s -and -c parameters kmod: fix wait on recursive loop wait: add wait_event_killable_timeout() kernel/watchdog: fix Kconfig constraints for perf hardlockup watchdog mm: memcontrol: fix NULL pointer crash in test_clear_page_writeback()
| * | | | | | | mm: revert x86_64 and arm64 ELF_ET_DYN_BASE base changesKees Cook2017-08-182-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Moving the x86_64 and arm64 PIE base from 0x555555554000 to 0x000100000000 broke AddressSanitizer. This is a partial revert of: eab09532d400 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE") 02445990a96e ("arm64: move ELF_ET_DYN_BASE to 4GB / 4MB") The AddressSanitizer tool has hard-coded expectations about where executable mappings are loaded. The motivation for changing the PIE base in the above commits was to avoid the Stack-Clash CVEs that allowed executable mappings to get too close to heap and stack. This was mainly a problem on 32-bit, but the 64-bit bases were moved too, in an effort to proactively protect those systems (proofs of concept do exist that show 64-bit collisions, but other recent changes to fix stack accounting and setuid behaviors will minimize the impact). The new 32-bit PIE base is fine for ASan (since it matches the ET_EXEC base), so only the 64-bit PIE base needs to be reverted to let x86 and arm64 ASan binaries run again. Future changes to the 64-bit PIE base on these architectures can be made optional once a more dynamic method for dealing with AddressSanitizer is found. (e.g. always loading PIE into the mmap region for marked binaries.) Link: http://lkml.kernel.org/r/20170807201542.GA21271@beast Fixes: eab09532d400 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE") Fixes: 02445990a96e ("arm64: move ELF_ET_DYN_BASE to 4GB / 4MB") Signed-off-by: Kees Cook <keescook@chromium.org> Reported-by: Kostya Serebryany <kcc@google.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | mm/vmalloc.c: don't unconditonally use __GFP_HIGHMEMLaura Abbott2017-08-181-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 19809c2da28a ("mm, vmalloc: use __GFP_HIGHMEM implicitly") added use of __GFP_HIGHMEM for allocations. vmalloc_32 may use GFP_DMA/GFP_DMA32 which does not play nice with __GFP_HIGHMEM and will trigger a BUG in gfp_zone. Only add __GFP_HIGHMEM if we aren't using GFP_DMA/GFP_DMA32. Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1482249 Link: http://lkml.kernel.org/r/20170816220705.31374-1-labbott@redhat.com Fixes: 19809c2da28a ("mm, vmalloc: use __GFP_HIGHMEM implicitly") Signed-off-by: Laura Abbott <labbott@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | mm/mempolicy: fix use after free when calling get_mempolicyzhong jiang2017-08-181-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I hit a use after free issue when executing trinity and repoduced it with KASAN enabled. The related call trace is as follows. BUG: KASan: use after free in SyS_get_mempolicy+0x3c8/0x960 at addr ffff8801f582d766 Read of size 2 by task syz-executor1/798 INFO: Allocated in mpol_new.part.2+0x74/0x160 age=3 cpu=1 pid=799 __slab_alloc+0x768/0x970 kmem_cache_alloc+0x2e7/0x450 mpol_new.part.2+0x74/0x160 mpol_new+0x66/0x80 SyS_mbind+0x267/0x9f0 system_call_fastpath+0x16/0x1b INFO: Freed in __mpol_put+0x2b/0x40 age=4 cpu=1 pid=799 __slab_free+0x495/0x8e0 kmem_cache_free+0x2f3/0x4c0 __mpol_put+0x2b/0x40 SyS_mbind+0x383/0x9f0 system_call_fastpath+0x16/0x1b INFO: Slab 0xffffea0009cb8dc0 objects=23 used=8 fp=0xffff8801f582de40 flags=0x200000000004080 INFO: Object 0xffff8801f582d760 @offset=5984 fp=0xffff8801f582d600 Bytes b4 ffff8801f582d750: ae 01 ff ff 00 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a ........ZZZZZZZZ Object ffff8801f582d760: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff8801f582d770: 6b 6b 6b 6b 6b 6b 6b a5 kkkkkkk. Redzone ffff8801f582d778: bb bb bb bb bb bb bb bb ........ Padding ffff8801f582d8b8: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ Memory state around the buggy address: ffff8801f582d600: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801f582d680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8801f582d700: fc fc fc fc fc fc fc fc fc fc fc fc fb fb fb fc !shared memory policy is not protected against parallel removal by other thread which is normally protected by the mmap_sem. do_get_mempolicy, however, drops the lock midway while we can still access it later. Early premature up_read is a historical artifact from times when put_user was called in this path see https://lwn.net/Articles/124754/ but that is gone since 8bccd85ffbaf ("[PATCH] Implement sys_* do_* layering in the memory policy layer."). but when we have the the current mempolicy ref count model. The issue was introduced accordingly. Fix the issue by removing the premature release. Link: http://lkml.kernel.org/r/1502950924-27521-1-git-send-email-zhongjiang@huawei.com Signed-off-by: zhong jiang <zhongjiang@huawei.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: <stable@vger.kernel.org> [2.6+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | mm/cma_debug.c: fix stack corruption due to sprintf usagePrakash Gupta2017-08-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | name[] in cma_debugfs_add_one() can only accommodate 16 chars including NULL to store sprintf output. It's common for cma device name to be larger than 15 chars. This can cause stack corrpution. If the gcc stack protector is turned on, this can cause a panic due to stack corruption. Below is one example trace: Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffff8e69a75730 Call trace: dump_backtrace+0x0/0x2c4 show_stack+0x20/0x28 dump_stack+0xb8/0xf4 panic+0x154/0x2b0 print_tainted+0x0/0xc0 cma_debugfs_init+0x274/0x290 do_one_initcall+0x5c/0x168 kernel_init_freeable+0x1c8/0x280 Fix the short sprintf buffer in cma_debugfs_add_one() by using scnprintf() instead of sprintf(). Link: http://lkml.kernel.org/r/1502446217-21840-1-git-send-email-guptap@codeaurora.org Fixes: f318dd083c81 ("cma: Store a name in the cma structure") Signed-off-by: Prakash Gupta <guptap@codeaurora.org> Acked-by: Laura Abbott <labbott@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | signal: don't remove SIGNAL_UNKILLABLE for traced tasks.Jamie Iles2017-08-181-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When forcing a signal, SIGNAL_UNKILLABLE is removed to prevent recursive faults, but this is undesirable when tracing. For example, debugging an init process (whether global or namespace), hitting a breakpoint and SIGTRAP will force SIGTRAP and then remove SIGNAL_UNKILLABLE. Everything continues fine, but then once debugging has finished, the init process is left killable which is unlikely what the user expects, resulting in either an accidentally killed init or an init that stops reaping zombies. Link: http://lkml.kernel.org/r/20170815112806.10728-1-jamie.iles@oracle.com Signed-off-by: Jamie Iles <jamie.iles@oracle.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | mm, oom: fix potential data corruption when oom_reaper races with writerMichal Hocko2017-08-183-34/+64
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Wenwei Tao has noticed that our current assumption that the oom victim is dying and never doing any visible changes after it dies, and so the oom_reaper can tear it down, is not entirely true. __task_will_free_mem consider a task dying when SIGNAL_GROUP_EXIT is set but do_group_exit sends SIGKILL to all threads _after_ the flag is set. So there is a race window when some threads won't have fatal_signal_pending while the oom_reaper could start unmapping the address space. Moreover some paths might not check for fatal signals before each PF/g-u-p/copy_from_user. We already have a protection for oom_reaper vs. PF races by checking MMF_UNSTABLE. This has been, however, checked only for kernel threads (use_mm users) which can outlive the oom victim. A simple fix would be to extend the current check in handle_mm_fault for all tasks but that wouldn't be sufficient because the current check assumes that a kernel thread would bail out after EFAULT from get_user*/copy_from_user and never re-read the same address which would succeed because the PF path has established page tables already. This seems to be the case for the only existing use_mm user currently (virtio driver) but it is rather fragile in general. This is even more fragile in general for more complex paths such as generic_perform_write which can re-read the same address more times (e.g. iov_iter_copy_from_user_atomic to fail and then iov_iter_fault_in_readable on retry). Therefore we have to implement MMF_UNSTABLE protection in a robust way and never make a potentially corrupted content visible. That requires to hook deeper into the PF path and check for the flag _every time_ before a pte for anonymous memory is established (that means all !VM_SHARED mappings). The corruption can be triggered artificially (http://lkml.kernel.org/r/201708040646.v746kkhC024636@www262.sakura.ne.jp) but there doesn't seem to be any real life bug report. The race window should be quite tight to trigger most of the time. Link: http://lkml.kernel.org/r/20170807113839.16695-3-mhocko@kernel.org Fixes: aac453635549 ("mm, oom: introduce oom reaper") Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Wenwei Tao <wenwei.tww@alibaba-inc.com> Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Andrea Argangeli <andrea@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | mm: fix double mmap_sem unlock on MMF_UNSTABLE enforced SIGBUSMichal Hocko2017-08-181-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Tetsuo Handa has noticed that MMF_UNSTABLE SIGBUS path in handle_mm_fault causes a lockdep splat Out of memory: Kill process 1056 (a.out) score 603 or sacrifice child Killed process 1056 (a.out) total-vm:4268108kB, anon-rss:2246048kB, file-rss:0kB, shmem-rss:0kB a.out (1169) used greatest stack depth: 11664 bytes left DEBUG_LOCKS_WARN_ON(depth <= 0) ------------[ cut here ]------------ WARNING: CPU: 6 PID: 1339 at kernel/locking/lockdep.c:3617 lock_release+0x172/0x1e0 CPU: 6 PID: 1339 Comm: a.out Not tainted 4.13.0-rc3-next-20170803+ #142 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015 RIP: 0010:lock_release+0x172/0x1e0 Call Trace: up_read+0x1a/0x40 __do_page_fault+0x28e/0x4c0 do_page_fault+0x30/0x80 page_fault+0x28/0x30 The reason is that the page fault path might have dropped the mmap_sem and returned with VM_FAULT_RETRY. MMF_UNSTABLE check however rewrites the error path to VM_FAULT_SIGBUS and we always expect mmap_sem taken in that path. Fix this by taking mmap_sem when VM_FAULT_RETRY is held in the MMF_UNSTABLE path. We cannot simply add VM_FAULT_SIGBUS to the existing error code because all arch specific page fault handlers and g-u-p would have to learn a new error code combination. Link: http://lkml.kernel.org/r/20170807113839.16695-2-mhocko@kernel.org Fixes: 3f70dc38cec2 ("mm: make sure that kthreads will not refault oom reaped memory") Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Andrea Argangeli <andrea@kernel.org> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Wenwei Tao <wenwei.tww@alibaba-inc.com> Cc: <stable@vger.kernel.org> [4.9+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | slub: fix per memcg cache leak on css offlineVladimir Davydov2017-08-181-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To avoid a possible deadlock, sysfs_slab_remove() schedules an asynchronous work to delete sysfs entries corresponding to the kmem cache. To ensure the cache isn't freed before the work function is called, it takes a reference to the cache kobject. The reference is supposed to be released by the work function. However, the work function (sysfs_slab_remove_workfn()) does nothing in case the cache sysfs entry has already been deleted, leaking the kobject and the corresponding cache. This may happen on a per memcg cache destruction, because sysfs entries of a per memcg cache are deleted on memcg offline if the cache is empty (see __kmemcg_cache_deactivate()). The kmemleak report looks like this: unreferenced object 0xffff9f798a79f540 (size 32): comm "kworker/1:4", pid 15416, jiffies 4307432429 (age 28687.554s) hex dump (first 32 bytes): 6b 6d 61 6c 6c 6f 63 2d 31 36 28 31 35 39 39 3a kmalloc-16(1599: 6e 65 77 72 6f 6f 74 29 00 23 6b c0 ff ff ff ff newroot).#k..... backtrace: kmemleak_alloc+0x4a/0xa0 __kmalloc_track_caller+0x148/0x2c0 kvasprintf+0x66/0xd0 kasprintf+0x49/0x70 memcg_create_kmem_cache+0xe6/0x160 memcg_kmem_cache_create_func+0x20/0x110 process_one_work+0x205/0x5d0 worker_thread+0x4e/0x3a0 kthread+0x109/0x140 ret_from_fork+0x2a/0x40 unreferenced object 0xffff9f79b6136840 (size 416): comm "kworker/1:4", pid 15416, jiffies 4307432429 (age 28687.573s) hex dump (first 32 bytes): 40 fb 80 c2 3e 33 00 00 00 00 00 40 00 00 00 00 @...>3.....@.... 00 00 00 00 00 00 00 00 10 00 00 00 10 00 00 00 ................ backtrace: kmemleak_alloc+0x4a/0xa0 kmem_cache_alloc+0x128/0x280 create_cache+0x3b/0x1e0 memcg_create_kmem_cache+0x118/0x160 memcg_kmem_cache_create_func+0x20/0x110 process_one_work+0x205/0x5d0 worker_thread+0x4e/0x3a0 kthread+0x109/0x140 ret_from_fork+0x2a/0x40 Fix the leak by adding the missing call to kobject_put() to sysfs_slab_remove_workfn(). Link: http://lkml.kernel.org/r/20170812181134.25027-1-vdavydov.dev@gmail.com Fixes: 3b7b314053d02 ("slub: make sysfs file removal asynchronous") Signed-off-by: Vladimir Davydov <vdavydov.dev@gmail.com> Reported-by: Andrei Vagin <avagin@gmail.com> Tested-by: Andrei Vagin <avagin@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: <stable@vger.kernel.org> [4.12.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | mm: discard memblock data laterPavel Tatashin2017-08-184-39/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is existing use after free bug when deferred struct pages are enabled: The memblock_add() allocates memory for the memory array if more than 128 entries are needed. See comment in e820__memblock_setup(): * The bootstrap memblock region count maximum is 128 entries * (INIT_MEMBLOCK_REGIONS), but EFI might pass us more E820 entries * than that - so allow memblock resizing. This memblock memory is freed here: free_low_memory_core_early() We access the freed memblock.memory later in boot when deferred pages are initialized in this path: deferred_init_memmap() for_each_mem_pfn_range() __next_mem_pfn_range() type = &memblock.memory; One possible explanation for why this use-after-free hasn't been hit before is that the limit of INIT_MEMBLOCK_REGIONS has never been exceeded at least on systems where deferred struct pages were enabled. Tested by reducing INIT_MEMBLOCK_REGIONS down to 4 from the current 128, and verifying in qemu that this code is getting excuted and that the freed pages are sane. Link: http://lkml.kernel.org/r/1502485554-318703-2-git-send-email-pasha.tatashin@oracle.com Fixes: 7e18adb4f80b ("mm: meminit: initialise remaining struct pages in parallel with kswapd") Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Steven Sistare <steven.sistare@oracle.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
generated by cgit (git 2.34.1) at 2025-02-25 23:25:38 +0000