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* Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2014-07-27
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "A bunch of fixes for perf and kprobes: - revert a commit that caused a perf group regression - silence dmesg spam - fix kprobe probing errors on ia64 and ppc64 - filter kprobe faults from userspace - lockdep fix for perf exit path - prevent perf #GP in KVM guest - correct perf event and filters" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kprobes: Fix "Failed to find blacklist" probing errors on ia64 and ppc64 kprobes/x86: Don't try to resolve kprobe faults from userspace perf/x86/intel: Avoid spamming kernel log for BTS buffer failure perf/x86/intel: Protect LBR and extra_regs against KVM lying perf: Fix lockdep warning on process exit perf/x86/intel/uncore: Fix SNB-EP/IVT Cbox filter mappings perf/x86/intel: Use proper dTLB-load-misses event on IvyBridge perf: Revert ("perf: Always destroy groups on exit")
| * kprobes/x86: Don't try to resolve kprobe faults from userspaceAndy Lutomirski2014-07-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit: commit 6f6343f53d133bae516caf3d254bce37d8774625 Author: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Date: Thu Apr 17 17:17:33 2014 +0900 kprobes/x86: Call exception handlers directly from do_int3/do_debug appears to have inadvertently dropped a check that the int3 came from kernel mode. Trying to dereference addr when addr is user-controlled is completely bogus. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Link: http://lkml.kernel.org/r/c4e339882c121aa76254f2adde3fcbdf502faec2.1405099506.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf/x86/intel: Avoid spamming kernel log for BTS buffer failureDavid Rientjes2014-07-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's unnecessary to excessively spam the kernel log anytime the BTS buffer cannot be allocated, so make this allocation __GFP_NOWARN. The user probably will want to at least find some artifact that the allocation has failed in the past, probably due to fragmentation because of its large size, when it's not allocated at bootstrap. Thus, add a WARN_ONCE() so something is left behind for them to understand why perf commnads that require PEBS is not working properly. Signed-off-by: David Rientjes <rientjes@google.com> 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.2.02.1406301600460.26302@chino.kir.corp.google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf/x86/intel: Protect LBR and extra_regs against KVM lyingKan Liang2014-07-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With -cpu host, KVM reports LBR and extra_regs support, if the host has support. When the guest perf driver tries to access LBR or extra_regs MSR, it #GPs all MSR accesses,since KVM doesn't handle LBR and extra_regs support. So check the related MSRs access right once at initialization time to avoid the error access at runtime. For reproducing the issue, please build the kernel with CONFIG_KVM_INTEL = y (for host kernel). And CONFIG_PARAVIRT = n and CONFIG_KVM_GUEST = n (for guest kernel). Start the guest with -cpu host. Run perf record with --branch-any or --branch-filter in guest to trigger LBR Run perf stat offcore events (E.g. LLC-loads/LLC-load-misses ...) in guest to trigger offcore_rsp #GP Signed-off-by: Kan Liang <kan.liang@intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maria Dimakopoulou <maria.n.dimakopoulou@gmail.com> Cc: Mark Davies <junk@eslaf.co.uk> Cc: Paul Mackerras <paulus@samba.org> Cc: Stephane Eranian <eranian@google.com> Cc: Yan, Zheng <zheng.z.yan@intel.com> Link: http://lkml.kernel.org/r/1405365957-20202-1-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf/x86/intel/uncore: Fix SNB-EP/IVT Cbox filter mappingsStephane Eranian2014-07-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes the SNB-EP and IVT Cbox filter mapping table. The table controls which filters are supported by which events. There were several mistakes in those tables causing some filters to be ignored, such as NID on TOR_INSERTS. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: zheng.z.yan@intel.com Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20140630144624.GA2604@quad Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf/x86/intel: Use proper dTLB-load-misses event on IvyBridgeVince Weaver2014-07-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | x86: Merge tag 'ras_urgent' into x86/urgentH. Peter Anvin2014-07-24
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Promote one fix for 3.16 This fix was necessary after 9c15a24b038f ("x86/mce: Improve mcheck_init_device() error handling") went in. What this patch did was, among others, check the return value of misc_register and exit early if it encountered an error. Original code sloppily didn't do that. However, cef12ee52b05 ("xen/mce: Add mcelog support for Xen platform") made it so that xen's init routine xen_late_init_mcelog runs first. This was needed for the xen mcelog device which is supposed to be independent from the baremetal one. Initially it was reported that misc_register() fails often on xen and that's why it needed fixing. However, it is *supposed* to fail by design, when running in dom0 so that the xen mcelog device file gets registered first. And *then* you need the notifier *not* unregistered on the error path so that the timer does get deleted properly in the CPU hotplug notifier. Btw, this fix is needed also on baremetal in the unlikely event that misc_register(&mce_chrdev_device) fails there too. I was unsure whether to rush it in now and decided to delay it to 3.17. However, xen people wanted it promoted as it breaks xen when doing cpu hotplug there. So, after a bit of simmering in tip/master for initial smoke testing, let's move it to 3.16. It fixes a semi-regression which got introduced in 3.16 so no need for stable tagging. tip/x86/ras contains that exact same commit but we can't remove it there as it is not the last one. It won't cause any merge issues, as I confirmed locally but I should state here the special situation of this one fix explicitly anyway. Thanks. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * | x86, MCE: Robustify mcheck_init_deviceBorislav Petkov2014-07-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BorisO reports that misc_register() fails often on xen. The current code unregisters the CPU hotplug notifier in that case. If then a CPU is offlined and onlined back again, we end up with a second timer running on that CPU, leading to soft lockups and system hangs. So let's leave the hotcpu notifier always registered - even if mce_device_create failed for some cores and never unreg it so that we can deal with the timer handling accordingly. Reported-and-Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: http://lkml.kernel.org/r/1403274493-1371-1-git-send-email-boris.ostrovsky@oracle.com Signed-off-by: Borislav Petkov <bp@suse.de>
* | | x86, cpu: Fix cache topology for early P4-SMTPeter Zijlstra2014-07-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | P4 systems with cpuid level < 4 can have SMT, but the cache topology description available (cpuid2) does not include SMP information. Now we know that SMT shares all cache levels, and therefore we can mark all available cache levels as shared. We do this by setting cpu_llc_id to ->phys_proc_id, since that's the same for each SMT thread. We can do this unconditional since if there's no SMT its still true, the one CPU shares cache with only itself. This fixes a problem where such CPUs report an incorrect LLC CPU mask. This in turn fixes a crash in the scheduler where the topology was build wrong, it assumes the LLC mask to include at least the SMT CPUs. Cc: Josh Boyer <jwboyer@redhat.com> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Tested-by: Bruno Wolff III <bruno@wolff.to> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140722133514.GM12054@laptop.lan Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | | x86_32, entry: Store badsys error code in %eaxSven Wegener2014-07-22
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 554086d ("x86_32, entry: Do syscall exit work on badsys (CVE-2014-4508)") introduced a regression in the x86_32 syscall entry code, resulting in syscall() not returning proper errors for undefined syscalls on CPUs supporting the sysenter feature. The following code: > int result = syscall(666); > printf("result=%d errno=%d error=%s\n", result, errno, strerror(errno)); results in: > result=666 errno=0 error=Success Obviously, the syscall return value is the called syscall number, but it should have been an ENOSYS error. When run under ptrace it behaves correctly, which makes it hard to debug in the wild: > result=-1 errno=38 error=Function not implemented The %eax register is the return value register. For debugging via ptrace the syscall entry code stores the complete register context on the stack. The badsys handlers only store the ENOSYS error code in the ptrace register set and do not set %eax like a regular syscall handler would. The old resume_userspace call chain contains code that clobbers %eax and it restores %eax from the ptrace registers afterwards. The same goes for the ptrace-enabled call chain. When ptrace is not used, the syscall return value is the passed-in syscall number from the untouched %eax register. Use %eax as the return value register in syscall_badsys and sysenter_badsys, like a real syscall handler does, and have the caller push the value onto the stack for ptrace access. Signed-off-by: Sven Wegener <sven.wegener@stealer.net> Link: http://lkml.kernel.org/r/alpine.LNX.2.11.1407221022380.31021@titan.int.lan.stealer.net Reviewed-and-tested-by: Andy Lutomirski <luto@amacapital.net> Cc: <stable@vger.kernel.org> # If 554086d is backported Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2014-07-19
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Peter Anvin: "A couple of key fixes and a few less critical ones. The main ones are: - add a .bss section to the PE/COFF headers when building with EFI stub - invoke the correct paravirt magic when building the espfix page tables Unfortunately both of these areas also have at least one additional fix each still in thie pipeline, but which are not yet ready to push" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Remove unused variable "polling" x86/espfix/xen: Fix allocation of pages for paravirt page tables x86/efi: Include a .bss section within the PE/COFF headers efi: fdt: Do not report an error during boot if UEFI is not available efi/arm64: efistub: remove local copy of linux_banner
| * | x86: Remove unused variable "polling"Paul Bolle2014-07-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Compile tested. "polling" is unused since commit f80c5b39b80a ("sched/idle, x86: Switch from TS_POLLING to TIF_POLLING_NRFLAG"). Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Jiri Kosina <jkosina@suse.cz> Link: http://lkml.kernel.org/r/1404138749.2978.6.camel@x41 Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/espfix/xen: Fix allocation of pages for paravirt page tablesBoris Ostrovsky2014-07-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | init_espfix_ap() is currently off by one level when informing hypervisor that allocated pages will be used for ministacks' page tables. The most immediate effect of this on a PV guest is that if 'stack_page = __get_free_page()' returns a non-zeroed-out page the hypervisor will refuse to use it for a page table (which it shouldn't be anyway). This will result in warnings by both Xen and Linux. More importantly, a subsequent write to that page (again, by a PV guest) is likely to result in fatal page fault. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: http://lkml.kernel.org/r/1404926298-5565-1-git-send-email-boris.ostrovsky@oracle.com Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org>
* | | Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds2014-07-16
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "A cpufreq lockup fix and a compiler warning fix" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Fix compiler warnings x86, tsc: Fix cpufreq lockup
| * | | x86, tsc: Fix cpufreq lockupPeter Zijlstra2014-07-02
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mauro reported that his AMD X2 using the powernow-k8 cpufreq driver locked up when doing cpu hotplug. Because we called set_cyc2ns_scale() from the time_cpufreq_notifier() unconditionally, it gets called multiple times for each freq change, instead of only the once, when the tsc_khz value actually changes. Because it gets called more than once, we run out of cyc2ns data slots and stall, waiting for a free one, but because we're half way offline, there's no consumers to free slots. By placing the call inside the condition that actually changes tsc_khz we avoid superfluous calls and avoid the problem. Reported-by: Mauro <registosites@hotmail.com> Tested-by: Mauro <registosites@hotmail.com> Fixes: 20d1c86a5776 ("sched/clock, x86: Rewrite cyc2ns() to avoid the need to disable IRQs") Cc: <stable@vger.kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Bin Gao <bin.gao@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Stefani Seibold <stefani@seibold.net> Cc: linux-kernel@vger.kernel.org Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2014-07-16
|\ \ \ | |/ / |/| / | |/ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Tooling fixes and an Intel PMU driver fixlet" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Do not allow optimized switch for non-cloned events perf/x86/intel: ignore CondChgd bit to avoid false NMI handling perf symbols: Get kernel start address by symbol name perf tools: Fix segfault in cumulative.callchain report
| * perf/x86/intel: ignore CondChgd bit to avoid false NMI handlingHATAYAMA Daisuke2014-07-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, any NMI is falsely handled by a NMI handler of NMI watchdog if CondChgd bit in MSR_CORE_PERF_GLOBAL_STATUS MSR is set. For example, we use external NMI to make system panic to get crash dump, but in this case, the external NMI is falsely handled do to the issue. This commit deals with the issue simply by ignoring CondChgd bit. Here is explanation in detail. On x86 NMI watchdog uses performance monitoring feature to periodically signal NMI each time performance counter gets overflowed. intel_pmu_handle_irq() is called as a NMI_LOCAL handler from a NMI handler of NMI watchdog, perf_event_nmi_handler(). It identifies an owner of a given NMI by looking at overflow status bits in MSR_CORE_PERF_GLOBAL_STATUS MSR. If some of the bits are set, then it handles the given NMI as its own NMI. The problem is that the intel_pmu_handle_irq() doesn't distinguish CondChgd bit from other bits. Unlike the other status bits, CondChgd bit doesn't represent overflow status for performance counters. Thus, CondChgd bit cannot be thought of as a mark indicating a given NMI is NMI watchdog's. As a result, if CondChgd bit is set, any NMI is falsely handled by the NMI handler of NMI watchdog. Also, if type of the falsely handled NMI is either NMI_UNKNOWN, NMI_SERR or NMI_IO_CHECK, the corresponding action is never performed until CondChgd bit is cleared. I noticed this behavior on systems with Ivy Bridge processors: Intel Xeon CPU E5-2630 v2 and Intel Xeon CPU E7-8890 v2. On both systems, CondChgd bit in MSR_CORE_PERF_GLOBAL_STATUS MSR has already been set in the beginning at boot. Then the CondChgd bit is immediately cleared by next wrmsr to MSR_CORE_PERF_GLOBAL_CTRL MSR and appears to remain 0. On the other hand, on older processors such as Nehalem, Xeon E7540, CondChgd bit is not set in the beginning at boot. I'm not sure about exact behavior of CondChgd bit, in particular when this bit is set. Although I read Intel System Programmer's Manual to figure out that, the descriptions I found are: In 18.9.1: "The MSR_PERF_GLOBAL_STATUS MSR also provides a ¡sticky bit¢ to indicate changes to the state of performancmonitoring hardware" In Table 35-2 IA-32 Architectural MSRs 63 CondChg: status bits of this register has changed. These are different from the bahviour I see on the actual system as I explained above. At least, I think ignoring CondChgd bit should be enough for NMI watchdog perspective. Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Acked-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/20140625.103503.409316067.d.hatayama@jp.fujitsu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge branch 'x86/urgent' of ↵Linus Torvalds2014-06-27
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Peter Anvin: "A pile of fixes related to the VDSO, EFI and 32-bit badsys handling. It turns out that removing the section headers from the VDSO breaks gdb, so this puts back most of them. A very simple typo broke rt_sigreturn on some versions of glibc, with obviously disastrous results. The rest is pretty much fixes for the corresponding fallout. The EFI fixes fixes an arithmetic overflow on 32-bit systems and quiets some build warnings. Finally, when invoking an invalid system call number on x86-32, we bypass a bunch of handling, which can make the audit code oops" * 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: efi-pstore: Fix an overflow on 32-bit builds x86/vdso: Error out in vdso2c if DT_RELA is present x86/vdso: Move DISABLE_BRANCH_PROFILING into the vdso makefile x86_32, signal: Fix vdso rt_sigreturn x86_32, entry: Do syscall exit work on badsys (CVE-2014-4508) x86/vdso: Create .build-id links for unstripped vdso files x86/vdso: Remove some redundant in-memory section headers x86/vdso: Improve the fake section headers x86/vdso2c: Use better macros for ELF bitness x86/vdso: Discard the __bug_table section efi: Fix compiler warnings (unused, const, type)
| * | x86_32, signal: Fix vdso rt_sigreturnAndy Lutomirski2014-06-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit: commit 6f121e548f83674ab4920a4e60afb58d4f61b829 Author: Andy Lutomirski <luto@amacapital.net> Date: Mon May 5 12:19:34 2014 -0700 x86, vdso: Reimplement vdso.so preparation in build-time C Contained this obvious typo: - restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn); + restorer = current->mm->context.vdso + + selected_vdso32->sym___kernel_sigreturn; Note the missing 'rt_' in the new code. Fix it. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/1eb40ad923acde2e18357ef2832867432e70ac42.1403361010.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * | x86_32, entry: Do syscall exit work on badsys (CVE-2014-4508)Andy Lutomirski2014-06-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The bad syscall nr paths are their own incomprehensible route through the entry control flow. Rearrange them to work just like syscalls that return -ENOSYS. This fixes an OOPS in the audit code when fast-path auditing is enabled and sysenter gets a bad syscall nr (CVE-2014-4508). This has probably been broken since Linux 2.6.27: af0575bba0 i386 syscall audit fast-path Cc: stable@vger.kernel.org Cc: Roland McGrath <roland@redhat.com> Reported-by: Toralf Förster <toralf.foerster@gmx.de> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/e09c499eade6fc321266dd6b54da7beb28d6991c.1403558229.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | | nmi: provide the option to issue an NMI back trace to every cpu but currentAaron Tomlin2014-06-23
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sometimes it is preferred not to use the trigger_all_cpu_backtrace() routine when one wants to avoid capturing a back trace for current. For instance if one was previously captured recently. This patch provides a new routine namely trigger_allbutself_cpu_backtrace() which offers the flexibility to issue an NMI to every cpu but current and capture a back trace accordingly. Patch x86 and sparc to support new routine. [dzickus@redhat.com: add stub in #else clause] [dzickus@redhat.com: don't print message in single processor case, wrap with get/put_cpu based on Oleg's suggestion] [sfr@canb.auug.org.au: undo C99ism] Signed-off-by: Aaron Tomlin <atomlin@redhat.com> Signed-off-by: Don Zickus <dzickus@redhat.com> Acked-by: David S. Miller <davem@davemloft.net> Cc: Mateusz Guzik <mguzik@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | x86/kprobes: Fix build errors and blacklist context_track_userMasami Hiramatsu2014-06-14
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | This essentially reverts commit: ecd50f714c42 ("kprobes, x86: Call exception_enter after kprobes handled") since it causes build errors with CONFIG_CONTEXT_TRACKING and that has been made from misunderstandings; context_track_user_*() don't involve much in interrupt context, it just returns if in_interrupt() is true. Instead of changing the do_debug/int3(), this just adds context_track_user_*() to kprobes blacklist, since those are still can be called right before kprobes handles int3 and debug exceptions, and probing those will cause an infinite loop. Reported-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Borislav Petkov <bp@suse.de> Cc: Kees Cook <keescook@chromium.org> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/20140614064711.7865.45957.stgit@kbuild-fedora.novalocal Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'x86-irq-for-linus' of ↵Linus Torvalds2014-06-12
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 irq fixes from Ingo Molnar: "Two changes: a cpu-hotplug/irq race fix, plus a HyperV related fix" * 'x86-irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/irq: Fix fixup_irqs() error handling x86, irq, pic: Probe for legacy PIC and set legacy_pic appropriately
| * x86/irq: Fix fixup_irqs() error handlingPrarit Bhargava2014-04-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Several patches to fix cpu hotplug and the down'd cpu's irq relocations have been submitted in the past month or so. The patches should resolve the problems with cpu hotplug and irq relocation, however, there is always a possibility that a bug still exists. The big problem with debugging these irq reassignments is that the cpu down completes and then we get random stack traces from drivers for which irqs have not been properly assigned to a new cpu. The stack traces are a mix of storage, network, and other kernel subsystem (I once saw the serial port stop working ...) warnings and failures. The problem with these failures is that they are difficult to diagnose. There is no warning in the cpu hotplug down path to indicate that an IRQ has failed to be assigned to a new cpu, and all we are left with is a stack trace from a driver, or a non-functional device. If we had some information on the console debugging these situations would be much easier; after all we can map an IRQ to a device by simply using lspci or /proc/interrupts. The current code, fixup_irqs(), which migrates IRQs from the down'd cpu and is called close to the end of the cpu down path, calls chip->set_irq_affinity which eventually calls __assign_irq_vector(). Errors are not propogated back from this function call and this results in silent irq relocation failures. This patch fixes this issue by returning the error codes up the call stack and prints out a warning if there is a relocation failure. Signed-off-by: Prarit Bhargava <prarit@redhat.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Rui Wang <rui.y.wang@intel.com> Cc: Liu Ping Fan <kernelfans@gmail.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com> Cc: Lv Zheng <lv.zheng@intel.com> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Cc: Yang Zhang <yang.z.zhang@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Steven Rostedt (Red Hat) <rostedt@goodmis.org> Cc: Li Fei <fei.li@intel.com> Cc: gong.chen@linux.intel.com Link: http://lkml.kernel.org/r/1396440673-18286-1-git-send-email-prarit@redhat.com [ Made small cleanliness tweaks. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * x86, irq, pic: Probe for legacy PIC and set legacy_pic appropriatelyK. Y. Srinivasan2014-04-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The legacy PIC may or may not be available and we need a mechanism to detect the existence of the legacy PIC that is applicable for all hardware (both physical as well as virtual) currently supported by Linux. On Hyper-V, when our legacy firmware presented to the guests, emulates the legacy PIC while when our EFI based firmware is presented we do not emulate the PIC. To support Hyper-V EFI firmware, we had to set the legacy_pic to the null_legacy_pic since we had to bypass PIC based calibration in the early boot code. While, on the EFI firmware, we know we don't emulate the legacy PIC, we need a generic mechanism to detect the presence of the legacy PIC that is not based on boot time state - this became apparent when we tried to get kexec to work on Hyper-V EFI firmware. This patch implements the proposal put forth by H. Peter Anvin <hpa@linux.intel.com>: Write a known value to the PIC data port and read it back. If the value read is the value written, we do have the PIC, if not there is no PIC and we can safely set the legacy_pic to null_legacy_pic. Since the read from an unconnected I/O port returns 0xff, we will use ~(1 << PIC_CASCADE_IR) (0xfb: mask all lines except the cascade line) to probe for the existence of the PIC. In version V1 of the patch, I had cleaned up the code based on comments from Peter. In version V2 of the patch, I have addressed additional comments from Peter. In version V3 of the patch, I have addressed Jan's comments (JBeulich@suse.com). In version V4 of the patch, I have addressed additional comments from Peter. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Link: http://lkml.kernel.org/r/1397501029-29286-1-git-send-email-kys@microsoft.com Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2014-06-12
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more perf updates from Ingo Molnar: "A second round of perf updates: - wide reaching kprobes sanitization and robustization, with the hope of fixing all 'probe this function crashes the kernel' bugs, by Masami Hiramatsu. - uprobes updates from Oleg Nesterov: tmpfs support, corner case fixes and robustization work. - perf tooling updates and fixes from Jiri Olsa, Namhyung Ki, Arnaldo et al: * Add support to accumulate hist periods (Namhyung Kim) * various fixes, refactorings and enhancements" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits) perf: Differentiate exec() and non-exec() comm events perf: Fix perf_event_comm() vs. exec() assumption uprobes/x86: Rename arch_uprobe->def to ->defparam, minor comment updates perf/documentation: Add description for conditional branch filter perf/x86: Add conditional branch filtering support perf/tool: Add conditional branch filter 'cond' to perf record perf: Add new conditional branch filter 'PERF_SAMPLE_BRANCH_COND' uprobes: Teach copy_insn() to support tmpfs uprobes: Shift ->readpage check from __copy_insn() to uprobe_register() perf/x86: Use common PMU interrupt disabled code perf/ARM: Use common PMU interrupt disabled code perf: Disable sampled events if no PMU interrupt perf: Fix use after free in perf_remove_from_context() perf tools: Fix 'make help' message error perf record: Fix poll return value propagation perf tools: Move elide bool into perf_hpp_fmt struct perf tools: Remove elide setup for SORT_MODE__MEMORY mode perf tools: Fix "==" into "=" in ui_browser__warning assignment perf tools: Allow overriding sysfs and proc finding with env var perf tools: Consider header files outside perf directory in tags target ...
| * \ Merge branch 'perf/urgent' into perf/core, to resolve conflict and to ↵Ingo Molnar2014-06-06
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | prepare for new patches Conflicts: arch/x86/kernel/traps.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * \ \ Merge branch 'uprobes/core' of ↵Ingo Molnar2014-06-05
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/oleg/misc into perf/core Pull uprobes tmpfs support patches from Oleg Nesterov. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | uprobes/x86: Rename arch_uprobe->def to ->defparam, minor comment updatesOleg Nesterov2014-06-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Purely cosmetic, no changes in .o, 1. As Jim pointed out arch_uprobe->def looks ambiguous, rename it to ->defparam. 2. Add the comment into default_post_xol_op() to explain "regs->sp +=". 3. Remove the stale part of the comment in arch_uprobe_analyze_insn(). Suggested-by: Jim Keniston <jkenisto@us.ibm.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com>
| * | | | perf/x86: Add conditional branch filtering supportAnshuman Khandual2014-06-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds conditional branch filtering support, enabling it for PERF_SAMPLE_BRANCH_COND in perf branch stack sampling framework by utilizing an available software filter X86_BR_JCC. Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Reviewed-by: Stephane Eranian <eranian@google.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: mpe@ellerman.id.au Cc: benh@kernel.crashing.org Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1400743210-32289-3-git-send-email-khandual@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | perf/x86: Use common PMU interrupt disabled codeVince Weaver2014-06-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make the x86 perf code use the new common PMU interrupt disabled code. Typically most x86 machines have working PMU interrupts, although some older p6-class machines had this problem. 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.2.10.1405161715560.11099@vincent-weaver-1.umelst.maine.edu Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | Merge branch 'perf/kprobes' into perf/coreIngo Molnar2014-06-05
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/x86/kernel/traps.c The kprobes enhancements are fully cooked, ship them upstream. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | kprobes, x86: Use NOKPROBE_SYMBOL() instead of __kprobes annotationMasami Hiramatsu2014-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use NOKPROBE_SYMBOL macro for protecting functions from kprobes instead of __kprobes annotation under arch/x86. This applies nokprobe_inline annotation for some cases, because NOKPROBE_SYMBOL() will inhibit inlining by referring the symbol address. This just folds a bunch of previous NOKPROBE_SYMBOL() cleanup patches for x86 to one patch. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Link: http://lkml.kernel.org/r/20140417081814.26341.51656.stgit@ltc230.yrl.intra.hitachi.co.jp Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fernando Luis Vázquez Cao <fernando_b1@lab.ntt.co.jp> Cc: Gleb Natapov <gleb@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Lebon <jlebon@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matt Fleming <matt.fleming@intel.com> Cc: Michel Lespinasse <walken@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | kprobes, x86: Allow kprobes on text_poke/hw_breakpointMasami Hiramatsu2014-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow kprobes on text_poke/hw_breakpoint because those are not related to the critical int3-debug recursive path of kprobes at this moment. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@suse.de> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Link: http://lkml.kernel.org/r/20140417081807.26341.73219.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | kprobes/x86: Allow probe on some kprobe preparation functionsMasami Hiramatsu2014-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no need to prohibit probing on the functions used in preparation phase. Those are safely probed because those are not invoked from breakpoint/fault/debug handlers, there is no chance to cause recursive exceptions. Following functions are now removed from the kprobes blacklist: can_boost can_probe can_optimize is_IF_modifier __copy_instruction copy_optimized_instructions arch_copy_kprobe arch_prepare_kprobe arch_arm_kprobe arch_disarm_kprobe arch_remove_kprobe arch_trampoline_kprobe arch_prepare_kprobe_ftrace arch_prepare_optimized_kprobe arch_check_optimized_kprobe arch_within_optimized_kprobe __arch_remove_optimized_kprobe arch_remove_optimized_kprobe arch_optimize_kprobes arch_unoptimize_kprobe I tested those functions by putting kprobes on all instructions in the functions with the bash script I sent to LKML. See: https://lkml.org/lkml/2014/3/27/33 Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jonathan Lebon <jlebon@redhat.com> Link: http://lkml.kernel.org/r/20140417081747.26341.36065.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | kprobes, x86: Call exception_enter after kprobes handledMasami Hiramatsu2014-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move exception_enter() call after kprobes handler is done. Since the exception_enter() involves many other functions (like printk), it can cause recursive int3/break loop when kprobes probe such functions. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@suse.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Kees Cook <keescook@chromium.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Link: http://lkml.kernel.org/r/20140417081740.26341.10894.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | kprobes/x86: Call exception handlers directly from do_int3/do_debugMasami Hiramatsu2014-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To avoid a kernel crash by probing on lockdep code, call kprobe_int3_handler() and kprobe_debug_handler()(which was formerly called post_kprobe_handler()) directly from do_int3 and do_debug. Currently kprobes uses notify_die() to hook the int3/debug exceptoins. Since there is a locking code in notify_die, the lockdep code can be invoked. And because the lockdep involves printk() related things, theoretically, we need to prohibit probing on such code, which means much longer blacklist we'll have. Instead, hooking the int3/debug for kprobes before notify_die() can avoid this problem. Anyway, most of the int3 handlers in the kernel are already called from do_int3 directly, e.g. ftrace_int3_handler, poke_int3_handler, kgdb_ll_trap. Actually only kprobe_exceptions_notify is on the notifier_call_chain. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@suse.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jonathan Lebon <jlebon@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Link: http://lkml.kernel.org/r/20140417081733.26341.24423.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | kprobes, x86: Prohibit probing on native_set_debugreg()/load_idt()Masami Hiramatsu2014-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the kprobes uses do_debug for single stepping, functions called from do_debug() before notify_die() must not be probed. And also native_load_idt() is called from paranoid_exit when returning int3, this also must not be probed. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Alok Kataria <akataria@vmware.com> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: virtualization@lists.linux-foundation.org Link: http://lkml.kernel.org/r/20140417081719.26341.65542.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | kprobes, x86: Prohibit probing on debug_stack_*()Masami Hiramatsu2014-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Prohibit probing on debug_stack_reset and debug_stack_set_zero. Since the both functions are called from TRACE_IRQS_ON/OFF_DEBUG macros which run in int3 ist entry, probing it may cause a soft lockup. This happens when the kernel built with CONFIG_DYNAMIC_FTRACE=y and CONFIG_TRACE_IRQFLAGS=y. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Jan Beulich <JBeulich@suse.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Link: http://lkml.kernel.org/r/20140417081712.26341.32994.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | kprobes: Introduce NOKPROBE_SYMBOL() macro to maintain kprobes blacklistMasami Hiramatsu2014-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce NOKPROBE_SYMBOL() macro which builds a kprobes blacklist at kernel build time. The usage of this macro is similar to EXPORT_SYMBOL(), placed after the function definition: NOKPROBE_SYMBOL(function); Since this macro will inhibit inlining of static/inline functions, this patch also introduces a nokprobe_inline macro for static/inline functions. In this case, we must use NOKPROBE_SYMBOL() for the inline function caller. When CONFIG_KPROBES=y, the macro stores the given function address in the "_kprobe_blacklist" section. Since the data structures are not fully initialized by the macro (because there is no "size" information), those are re-initialized at boot time by using kallsyms. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Link: http://lkml.kernel.org/r/20140417081705.26341.96719.stgit@ltc230.yrl.intra.hitachi.co.jp Cc: Alok Kataria <akataria@vmware.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christopher Li <sparse@chrisli.org> Cc: Chris Wright <chrisw@sous-sol.org> Cc: David S. Miller <davem@davemloft.net> Cc: Jan-Simon Möller <dl9pf@gmx.de> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: linux-arch@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-sparse@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | kprobes: Prohibit probing on .entry.text codeMasami Hiramatsu2014-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | .entry.text is a code area which is used for interrupt/syscall entries, which includes many sensitive code. Thus, it is better to prohibit probing on all of such code instead of a part of that. Since some symbols are already registered on kprobe blacklist, this also removes them from the blacklist. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David S. Miller <davem@davemloft.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jonathan Lebon <jlebon@redhat.com> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Link: http://lkml.kernel.org/r/20140417081658.26341.57354.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | kprobes/x86: Allow to handle reentered kprobe on single-steppingMasami Hiramatsu2014-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the NMI handlers(e.g. perf) can interrupt in the single stepping (or preparing the single stepping, do_debug etc.), we should consider a kprobe is hit in the NMI handler. Even in that case, the kprobe is allowed to be reentered as same as the kprobes hit in kprobe handlers (KPROBE_HIT_ACTIVE or KPROBE_HIT_SSDONE). The real issue will happen when a kprobe hit while another reentered kprobe is processing (KPROBE_REENTER), because we already consumed a saved-area for the previous kprobe. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jonathan Lebon <jlebon@redhat.com> Link: http://lkml.kernel.org/r/20140417081651.26341.10593.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | Merge branch 'perf/uprobes' into perf/coreIngo Molnar2014-06-05
| |\ \ \ \ \ | | | |/ / / | | |/| | | | | | | | | | | | | | | | | | | | | These bits from Oleg are fully cooked, ship them to Linus. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | uprobes/x86: Fix the wrong ->si_addr when xol triggers a trapOleg Nesterov2014-05-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the probed insn triggers a trap, ->si_addr = regs->ip is technically correct, but this is not what the signal handler wants; we need to pass the address of the probed insn, not the address of xol slot. Add the new arch-agnostic helper, uprobe_get_trap_addr(), and change fill_trap_info() and math_error() to use it. !CONFIG_UPROBES case in uprobes.h uses a macro to avoid include hell and ensure that it can be compiled even if an architecture doesn't define instruction_pointer(). Test-case: #include <signal.h> #include <stdio.h> #include <unistd.h> extern void probe_div(void); void sigh(int sig, siginfo_t *info, void *c) { int passed = (info->si_addr == probe_div); printf(passed ? "PASS\n" : "FAIL\n"); _exit(!passed); } int main(void) { struct sigaction sa = { .sa_sigaction = sigh, .sa_flags = SA_SIGINFO, }; sigaction(SIGFPE, &sa, NULL); asm ( "xor %ecx,%ecx\n" ".globl probe_div; probe_div:\n" "idiv %ecx\n" ); return 0; } it fails if probe_div() is probed. Note: show_unhandled_signals users should probably use this helper too, but we need to cleanup them first. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
| | * | | | x86/traps: Kill DO_ERROR_INFO()Oleg Nesterov2014-05-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that DO_ERROR_INFO() doesn't differ from DO_ERROR() we can remove it and use DO_ERROR() instead. Signed-off-by: Oleg Nesterov <oleg@redhat.com>
| | * | | | x86/traps: Shift fill_trap_info() from DO_ERROR_INFO() to do_error_trap()Oleg Nesterov2014-05-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the callsite of fill_trap_info() into do_error_trap() and remove the "siginfo_t *info" argument. This obviously breaks DO_ERROR() which passed info == NULL, we simply change fill_trap_info() to return "siginfo_t *" and add the "default" case which returns SEND_SIG_PRIV. Signed-off-by: Oleg Nesterov <oleg@redhat.com>
| | * | | | x86/traps: Introduce fill_trap_info(), simplify DO_ERROR_INFO()Oleg Nesterov2014-05-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Extract the fill-siginfo code from DO_ERROR_INFO() into the new helper, fill_trap_info(). It can calculate si_code and si_addr looking at trapnr, so we can remove these arguments from DO_ERROR_INFO() and simplify the source code. The generated code is the same, __builtin_constant_p(trapnr) == T. Signed-off-by: Oleg Nesterov <oleg@redhat.com>
| | * | | | x86/traps: Introduce do_error_trap()Oleg Nesterov2014-05-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the common code from DO_ERROR() and DO_ERROR_INFO() into the new helper, do_error_trap(). This simplifies define's and shaves 527 bytes from traps.o. Signed-off-by: Oleg Nesterov <oleg@redhat.com>
| | * | | | x86/traps: Use SEND_SIG_PRIV instead of force_sig()Oleg Nesterov2014-05-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | force_sig() is just force_sig_info(SEND_SIG_PRIV). Imho it should die, we have too many ugly "send signal" helpers. And do_trap() looks just ugly because it uses force_sig_info() or force_sig() depending on info != NULL. Signed-off-by: Oleg Nesterov <oleg@redhat.com>
| | * | | | x86/traps: Make math_error() staticOleg Nesterov2014-05-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Trivial, make math_error() static. Signed-off-by: Oleg Nesterov <oleg@redhat.com>
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