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2014-12-19Merge branch 'x86-apic-for-linus' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic updates from Thomas Gleixner: "After stopping the full x86/apic branch, I took some time to go through the first block of patches again, which are mostly cleanups and preparatory work for the irqdomain conversion and ioapic hotplug support. Unfortunaly one of the real problematic commits was right at the beginning, so I rebased this portion of the pending patches without the offenders. It would be great to get this into 3.19. That makes reworking the problematic parts simpler. The usual tip testing did not unearth any issues and it is fully bisectible now. I'm pretty confident that this wont affect the calmness of the xmas season. Changes: - Split the convoluted io_apic.c code into domain specific parts (vector, ioapic, msi, htirq) - Introduce proper helper functions to retrieve irq specific data instead of open coded dereferencing of pointers - Preparatory work for ioapic hotplug and irqdomain conversion - Removal of the non functional pci-ioapic driver - Removal of unused irq entry stubs - Make native_smp_prepare_cpus() preemtible to avoid GFP_ATOMIC allocations for everything which is called from there. - Small cleanups and fixes" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) iommu/amd: Use helpers to access irq_cfg data structure associated with IRQ iommu/vt-d: Use helpers to access irq_cfg data structure associated with IRQ x86: irq_remapping: Use helpers to access irq_cfg data structure associated with IRQ x86, irq: Use helpers to access irq_cfg data structure associated with IRQ x86, irq: Make MSI and HT_IRQ indepenent of X86_IO_APIC x86, irq: Move IRQ initialization routines from io_apic.c into vector.c x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.h x86, irq: Move HT IRQ related code from io_apic.c into htirq.c x86, irq: Move PCI MSI related code from io_apic.c into msi.c x86, irq: Replace printk(KERN_LVL) with pr_lvl() utilities x86, irq: Make UP version of irq_complete_move() an inline stub x86, irq: Move local APIC related code from io_apic.c into vector.c x86, irq: Introduce helpers to access struct irq_cfg x86, irq: Protect __clear_irq_vector() with vector_lock x86, irq: Rename local APIC related functions in io_apic.c as apic_xxx() x86, irq: Refine hw_irq.h to prepare for irqdomain support x86, irq: Convert irq_2_pin list to generic list x86, irq: Kill useless parameter 'irq_attr' of IO_APIC_get_PCI_irq_vector() x86, irq, acpi: Get rid of special handling of GSI for ACPI SCI x86, irq: Introduce helper to check whether an IOAPIC has been registered ...
2014-12-16x86: Avoid building unused IRQ entry stubsJan Beulich1-2/+2
When X86_LOCAL_APIC (i.e. unconditionally on x86-64), first_system_vector will never end up being higher than LOCAL_TIMER_VECTOR (0xef), and hence building stubs for vectors 0xef...0xff is pointlessly reducing code density. Deal with this at build time already. Taking into consideration that X86_64 implies X86_LOCAL_APIC, also simplify (and hence make easier to read and more consistent with the change done here) some #if-s in arch/x86/kernel/irqinit.c. While we could further improve the packing of the IRQ entry stubs (the four ones now left in the last set could be fit into the four padding bytes each of the final four sets have) this doesn't seem to provide any real benefit: Both irq_entries_start and common_interrupt getting cache line aligned, eliminating the 30th set would just produce 32 bytes of padding between the 29th and common_interrupt. [ tglx: Folded lguest fix from Dan Carpenter ] Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: lguest@lists.ozlabs.org Cc: Rusty Russell <rusty@rustcorp.com.au> Link: http://lkml.kernel.org/r/54574D5F0200007800044389@mail.emea.novell.com Link: http://lkml.kernel.org/r/20141115185718.GB6530@mwanda Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-13Merge tag 'trace-fixes-v3.18' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Here's two fixes: 1) Discovered by Fengguang Wu's tests. I changed the parameters to the function graph x86 prepare_ftrace_return call but forgot to update the call from entry_32 (i386 version). This patch corrects that. 2) I was tracing some code and found that the sched_switch tracepoint was showing tasks in the INTERRUPTIBLE state as RUNNING. This was due to the updates to convert preempt_count into a per_cpu variable. The tracepoint logic was made to use the tasks saved_preempt_count which could hold a stale "PREEMPT_ACTIVE", instead of using the current preempt_count() call" * tag 'trace-fixes-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/sched: Check preempt_count() for current when reading task->state ftrace/x86: Update i386 call to prepare_ftrace_return()
2014-12-11ftrace/x86: Update i386 call to prepare_ftrace_return()Steven Rostedt (Red Hat)1-3/+3
The parameters for prepare_ftrace_return() used by the function graph tracer were swapped to simplify the code on x86_64. But i386 function graph trampoline also calls this function, and it did not have its parameters swapped. Link: http://lkml.kernel.org/r/20141210231732.GA24163@wfg-t540p.sh.intel.com Reported-by: Fengguang Wu <fengguang.wu@intel.com> Tested-by: Fengguang Wu <fengguang.wu@intel.com> Fixes: 6a06bdbf7f9c "ftrace/fgraph/x86: Have prepare_ftrace_return() take ip as first parameter" Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-10-24i386/audit: stop scribbling on the stack frameEric Paris1-8/+7
git commit b4f0d3755c5e9cc86292d5fd78261903b4f23d4a was very very dumb. It was writing over %esp/pt_regs semi-randomly on i686 with the expected "system can't boot" results. As noted in: https://bugs.freedesktop.org/show_bug.cgi?id=85277 This patch stops fscking with pt_regs. Instead it sets up the registers for the call to __audit_syscall_entry in the most obvious conceivable way. It then does just a tiny tiny touch of magic. We need to get what started in PT_EDX into 0(%esp) and PT_ESI into 4(%esp). This is as easy as a pair of pushes. After the call to __audit_syscall_entry all we need to do is get that now useless junk off the stack (pair of pops) and reload %eax with the original syscall so other stuff can keep going about it's business. Reported-by: Paulo Zanoni <przanoni@gmail.com> Signed-off-by: Eric Paris <eparis@redhat.com> Link: http://lkml.kernel.org/r/1414037043-30647-1-git-send-email-eparis@redhat.com Cc: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-10-19Merge git://git.infradead.org/users/eparis/auditLinus Torvalds1-6/+5
Pull audit updates from Eric Paris: "So this change across a whole bunch of arches really solves one basic problem. We want to audit when seccomp is killing a process. seccomp hooks in before the audit syscall entry code. audit_syscall_entry took as an argument the arch of the given syscall. Since the arch is part of what makes a syscall number meaningful it's an important part of the record, but it isn't available when seccomp shoots the syscall... For most arch's we have a better way to get the arch (syscall_get_arch) So the solution was two fold: Implement syscall_get_arch() everywhere there is audit which didn't have it. Use syscall_get_arch() in the seccomp audit code. Having syscall_get_arch() everywhere meant it was a useless flag on the stack and we could get rid of it for the typical syscall entry. The other changes inside the audit system aren't grand, fixed some records that had invalid spaces. Better locking around the task comm field. Removing some dead functions and structs. Make some things static. Really minor stuff" * git://git.infradead.org/users/eparis/audit: (31 commits) audit: rename audit_log_remove_rule to disambiguate for trees audit: cull redundancy in audit_rule_change audit: WARN if audit_rule_change called illegally audit: put rule existence check in canonical order next: openrisc: Fix build audit: get comm using lock to avoid race in string printing audit: remove open_arg() function that is never used audit: correct AUDIT_GET_FEATURE return message type audit: set nlmsg_len for multicast messages. audit: use union for audit_field values since they are mutually exclusive audit: invalid op= values for rules audit: use atomic_t to simplify audit_serial() kernel/audit.c: use ARRAY_SIZE instead of sizeof/sizeof[0] audit: reduce scope of audit_log_fcaps audit: reduce scope of audit_net_id audit: arm64: Remove the audit arch argument to audit_syscall_entry arm64: audit: Add audit hook in syscall_trace_enter/exit() audit: x86: drop arch from __audit_syscall_entry() interface sparc: implement is_32bit_task sparc: properly conditionalize use of TIF_32BIT ...
2014-09-23audit: x86: drop arch from __audit_syscall_entry() interfaceRichard Guy Briggs1-6/+5
Since the arch is found locally in __audit_syscall_entry(), there is no need to pass it in as a parameter. Delete it from the parameter list. x86* was the only arch to call __audit_syscall_entry() directly and did so from assembly code. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-audit@redhat.com Signed-off-by: Eric Paris <eparis@redhat.com> --- As this patch relies on changes in the audit tree, I think it appropriate to send it through my tree rather than the x86 tree.
2014-08-15x86_32, entry: Clean up sysenter_badsys declarationStefan Bader1-1/+1
commit 554086d85e "x86_32, entry: Do syscall exit work on badsys (CVE-2014-4508)" introduced a new jump label (sysenter_badsys) but somehow the END statements seem to have gone wrong (at least it feels that way to me). This does not seem to be a fatal problem, but just for the sake of symmetry, change the second syscall_badsys to sysenter_badsys. Signed-off-by: Stefan Bader <stefan.bader@canonical.com> Link: http://lkml.kernel.org/r/1408093066-31021-1-git-send-email-stefan.bader@canonical.com Acked-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-08-04Merge tag 'trace-3.17' of ↵Linus Torvalds1-9/+0
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "This pull request has a lot of work done. The main thing is the changes to the ftrace function callback infrastructure. It's introducing a way to allow different functions to call directly different trampolines instead of all calling the same "mcount" one. The only user of this for now is the function graph tracer, which always had a different trampoline, but the function tracer trampoline was called and did basically nothing, and then the function graph tracer trampoline was called. The difference now, is that the function graph tracer trampoline can be called directly if a function is only being traced by the function graph trampoline. If function tracing is also happening on the same function, the old way is still done. The accounting for this takes up more memory when function graph tracing is activated, as it needs to keep track of which functions it uses. I have a new way that wont take as much memory, but it's not ready yet for this merge window, and will have to wait for the next one. Another big change was the removal of the ftrace_start/stop() calls that were used by the suspend/resume code that stopped function tracing when entering into suspend and resume paths. The stop of ftrace was done because there was some function that would crash the system if one called smp_processor_id()! The stop/start was a big hammer to solve the issue at the time, which was when ftrace was first introduced into Linux. Now ftrace has better infrastructure to debug such issues, and I found the problem function and labeled it with "notrace" and function tracing can now safely be activated all the way down into the guts of suspend and resume Other changes include clean ups of uprobe code, clean up of the trace_seq() code, and other various small fixes and clean ups to ftrace and tracing" * tag 'trace-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (57 commits) ftrace: Add warning if tramp hash does not match nr_trampolines ftrace: Fix trampoline hash update check on rec->flags ring-buffer: Use rb_page_size() instead of open coded head_page size ftrace: Rename ftrace_ops field from trampolines to nr_trampolines tracing: Convert local function_graph functions to static ftrace: Do not copy old hash when resetting tracing: let user specify tracing_thresh after selecting function_graph ring-buffer: Always run per-cpu ring buffer resize with schedule_work_on() tracing: Remove function_trace_stop and HAVE_FUNCTION_TRACE_MCOUNT_TEST s390/ftrace: remove check of obsolete variable function_trace_stop arm64, ftrace: Remove check of obsolete variable function_trace_stop Blackfin: ftrace: Remove check of obsolete variable function_trace_stop metag: ftrace: Remove check of obsolete variable function_trace_stop microblaze: ftrace: Remove check of obsolete variable function_trace_stop MIPS: ftrace: Remove check of obsolete variable function_trace_stop parisc: ftrace: Remove check of obsolete variable function_trace_stop sh: ftrace: Remove check of obsolete variable function_trace_stop sparc64,ftrace: Remove check of obsolete variable function_trace_stop tile: ftrace: Remove check of obsolete variable function_trace_stop ftrace: x86: Remove check of obsolete variable function_trace_stop ...
2014-07-22x86_32, entry: Store badsys error code in %eaxSven Wegener1-4/+5
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>
2014-07-18ftrace: x86: Remove check of obsolete variable function_trace_stopSteven Rostedt (Red Hat)1-9/+0
Nothing sets function_trace_stop to disable function tracing anymore. Remove the check for it in the arch code. Link: http://lkml.kernel.org/r/53C54D32.6000000@zytor.com Acked-by: H. Peter Anvin <hpa@linux.intel.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-06-23x86_32, entry: Do syscall exit work on badsys (CVE-2014-4508)Andy Lutomirski1-2/+8
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>
2014-06-12Merge branch 'perf-core-for-linus' of ↵Linus Torvalds1-33/+0
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 ...
2014-05-04x86, espfix: Make it possible to disable 16-bit supportH. Peter Anvin1-0/+12
Embedded systems, which may be very memory-size-sensitive, are extremely unlikely to ever encounter any 16-bit software, so make it a CONFIG_EXPERT option to turn off support for any 16-bit software whatsoever. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1398816946-3351-1-git-send-email-hpa@linux.intel.com
2014-04-30x86-32, espfix: Remove filter for espfix32 due to raceH. Peter Anvin1-5/+0
It is not safe to use LAR to filter when to go down the espfix path, because the LDT is per-process (rather than per-thread) and another thread might change the descriptors behind our back. Fortunately it is always *safe* (if a bit slow) to go down the espfix path, and a 32-bit LDT stack segment is extremely rare. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1398816946-3351-1-git-send-email-hpa@linux.intel.com Cc: <stable@vger.kernel.org> # consider after upstream merge
2014-04-24kprobes: Prohibit probing on .entry.text codeMasami Hiramatsu1-33/+0
.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>
2014-01-09ftrace/x86: Load ftrace_ops in parameter not the variable holding itSteven Rostedt1-2/+2
Function tracing callbacks expect to have the ftrace_ops that registered it passed to them, not the address of the variable that holds the ftrace_ops that registered it. Use a mov instead of a lea to store the ftrace_ops into the parameter of the function tracing callback. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Link: http://lkml.kernel.org/r/20131113152004.459787f9@gandalf.local.home Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org> # v3.8+
2013-11-14Merge branch 'x86-trace-for-linus' of ↵Linus Torvalds1-0/+10
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/trace changes from Ingo Molnar: "This adds page fault tracepoints which have zero runtime cost in the disabled case via IDT trickery (no NOPs in the page fault hotpath)" * 'x86-trace-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, trace: Change user|kernel_page_fault to page_fault_user|kernel x86, trace: Add page fault tracepoints x86, trace: Delete __trace_alloc_intr_gate() x86, trace: Register exception handler to trace IDT x86, trace: Remove __alloc_intr_gate()
2013-11-08x86, trace: Register exception handler to trace IDTSeiji Aguchi1-0/+10
This patch registers exception handlers for tracing to a trace IDT. To implemented it in set_intr_gate(), this patch does followings. - Register the exception handlers to the trace IDT by prepending "trace_" to the handler's names. - Also, newly introduce trace_page_fault() to add tracepoints in a subsequent patch. Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com> Link: http://lkml.kernel.org/r/52716DEC.5050204@hds.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-09-25sched, x86: Provide a per-cpu preempt_count implementationPeter Zijlstra1-5/+2
Convert x86 to use a per-cpu preemption count. The reason for doing so is that accessing per-cpu variables is a lot cheaper than accessing thread_info variables. We still need to save/restore the actual preemption count due to PREEMPT_ACTIVE so we place the per-cpu __preempt_count variable in the same cache-line as the other hot __switch_to() variables such as current_task. NOTE: this save/restore is required even for !PREEMPT kernels as cond_resched() also relies on preempt_count's PREEMPT_ACTIVE to ignore task_struct::state. Also rename thread_info::preempt_count to ensure nobody is 'accidentally' still poking at it. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-gzn5rfsf8trgjoqx8hyayy3q@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-05x86-32, ftrace: Fix static ftrace when early microcode is enabledH. Peter Anvin1-0/+3
Early microcode loading runs C code before paging is enabled on 32 bits. Since ftrace puts a hook into every function, that hook needs to be safe to execute in the pre-paging environment. This is currently true for dynamic ftrace but not for static ftrace. Static ftrace is obsolescent and assumed to not be performance-critical, so we can simply test that the stack pointer falls within the valid range of kernel addresses. Reported-by: Jan Kiszka <jan.kiszka@siemens.com> Tested-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-06-20x86, trace: Add irq vector tracepointsSeiji Aguchi1-1/+11
[Purpose of this patch] As Vaibhav explained in the thread below, tracepoints for irq vectors are useful. http://www.spinics.net/lists/mm-commits/msg85707.html <snip> The current interrupt traces from irq_handler_entry and irq_handler_exit provide when an interrupt is handled. They provide good data about when the system has switched to kernel space and how it affects the currently running processes. There are some IRQ vectors which trigger the system into kernel space, which are not handled in generic IRQ handlers. Tracing such events gives us the information about IRQ interaction with other system events. The trace also tells where the system is spending its time. We want to know which cores are handling interrupts and how they are affecting other processes in the system. Also, the trace provides information about when the cores are idle and which interrupts are changing that state. <snip> On the other hand, my usecase is tracing just local timer event and getting a value of instruction pointer. I suggested to add an argument local timer event to get instruction pointer before. But there is another way to get it with external module like systemtap. So, I don't need to add any argument to irq vector tracepoints now. [Patch Description] Vaibhav's patch shared a trace point ,irq_vector_entry/irq_vector_exit, in all events. But there is an above use case to trace specific irq_vector rather than tracing all events. In this case, we are concerned about overhead due to unwanted events. So, add following tracepoints instead of introducing irq_vector_entry/exit. so that we can enable them independently. - local_timer_vector - reschedule_vector - call_function_vector - call_function_single_vector - irq_work_entry_vector - error_apic_vector - thermal_apic_vector - threshold_apic_vector - spurious_apic_vector - x86_platform_ipi_vector Also, introduce a logic switching IDT at enabling/disabling time so that a time penalty makes a zero when tracepoints are disabled. Detailed explanations are as follows. - Create trace irq handlers with entering_irq()/exiting_irq(). - Create a new IDT, trace_idt_table, at boot time by adding a logic to _set_gate(). It is just a copy of original idt table. - Register the new handlers for tracpoints to the new IDT by introducing macros to alloc_intr_gate() called at registering time of irq_vector handlers. - Add checking, whether irq vector tracing is on/off, into load_current_idt(). This has to be done below debug checking for these reasons. - Switching to debug IDT may be kicked while tracing is enabled. - On the other hands, switching to trace IDT is kicked only when debugging is disabled. In addition, the new IDT is created only when CONFIG_TRACING is enabled to avoid being used for other purposes. Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com> Link: http://lkml.kernel.org/r/51C323ED.5050708@hds.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org>
2013-02-23Merge branch 'for-linus' of ↵Linus Torvalds1-45/+0
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull signal handling cleanups from Al Viro: "This is the first pile; another one will come a bit later and will contain SYSCALL_DEFINE-related patches. - a bunch of signal-related syscalls (both native and compat) unified. - a bunch of compat syscalls switched to COMPAT_SYSCALL_DEFINE (fixing several potential problems with missing argument validation, while we are at it) - a lot of now-pointless wrappers killed - a couple of architectures (cris and hexagon) forgot to save altstack settings into sigframe, even though they used the (uninitialized) values in sigreturn; fixed. - microblaze fixes for delivery of multiple signals arriving at once - saner set of helpers for signal delivery introduced, several architectures switched to using those." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (143 commits) x86: convert to ksignal sparc: convert to ksignal arm: switch to struct ksignal * passing alpha: pass k_sigaction and siginfo_t using ksignal pointer burying unused conditionals make do_sigaltstack() static arm64: switch to generic old sigaction() (compat-only) arm64: switch to generic compat rt_sigaction() arm64: switch compat to generic old sigsuspend arm64: switch to generic compat rt_sigqueueinfo() arm64: switch to generic compat rt_sigpending() arm64: switch to generic compat rt_sigprocmask() arm64: switch to generic sigaltstack sparc: switch to generic old sigsuspend sparc: COMPAT_SYSCALL_DEFINE does all sign-extension as well as SYSCALL_DEFINE sparc: kill sign-extending wrappers for native syscalls kill sparc32_open() sparc: switch to use of generic old sigaction sparc: switch sys_compat_rt_sigaction() to COMPAT_SYSCALL_DEFINE mips: switch to generic sys_fork() and sys_clone() ...
2013-02-12X86: Handle Hyper-V vmbus interrupts as special hypervisor interruptsK. Y. Srinivasan1-1/+8
Starting with win8, vmbus interrupts can be delivered on any VCPU in the guest and furthermore can be concurrently active on multiple VCPUs. Support this interrupt delivery model by setting up a separate IDT entry for Hyper-V vmbus. interrupts. I would like to thank Jan Beulich <JBeulich@suse.com> and Thomas Gleixner <tglx@linutronix.de>, for their help. In this version of the patch, based on the feedback, I have merged the IDT vector for Xen and Hyper-V and made the necessary adjustments. Furhermore, based on Jan's feedback I have added the necessary compilation switches. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Link: http://lkml.kernel.org/r/1359940959-32168-3-git-send-email-kys@microsoft.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-02-03x86: get rid of pt_regs argument in vm86/vm86oldAl Viro1-21/+0
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03x86: get rid of pt_regs argument in sigreturn variantsAl Viro1-23/+0
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03x86: get rid of pt_regs argument of iopl(2)Al Viro1-1/+0
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-01-18Merge tag 'stable/for-linus-3.8-rc3-tag' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen fixes from Konrad Rzeszutek Wilk: - CVE-2013-0190/XSA-40 (or stack corruption for 32-bit PV kernels) - Fix racy vma access spotted by Al Viro - Fix mmap batch ioctl potentially resulting in large O(n) page allcations. - Fix vcpu online/offline BUG:scheduling while atomic.. - Fix unbound buffer scanning for more than 32 vCPUs. - Fix grant table being incorrectly initialized - Fix incorrect check in pciback - Allow privcmd in backend domains. Fix up whitespace conflict due to ugly merge resolution in Xen tree in arch/arm/xen/enlighten.c * tag 'stable/for-linus-3.8-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: Fix stack corruption in xen_failsafe_callback for 32bit PVOPS guests. Revert "xen/smp: Fix CPU online/offline bug triggering a BUG: scheduling while atomic." xen/gntdev: remove erronous use of copy_to_user xen/gntdev: correctly unmap unlinked maps in mmu notifier xen/gntdev: fix unsafe vma access xen/privcmd: Fix mmap batch ioctl. Xen: properly bound buffer access when parsing cpu/*/availability xen/grant-table: correctly initialize grant table version 1 x86/xen : Fix the wrong check in pciback xen/privcmd: Relax access control in privcmd_ioctl_mmap
2013-01-16xen: Fix stack corruption in xen_failsafe_callback for 32bit PVOPS guests.Andrew Cooper1-1/+0
This fixes CVE-2013-0190 / XSA-40 There has been an error on the xen_failsafe_callback path for failed iret, which causes the stack pointer to be wrong when entering the iret_exc error path. This can result in the kernel crashing. In the classic kernel case, the relevant code looked a little like: popl %eax # Error code from hypervisor jz 5f addl $16,%esp jmp iret_exc # Hypervisor said iret fault 5: addl $16,%esp # Hypervisor said segment selector fault Here, there are two identical addls on either option of a branch which appears to have been optimised by hoisting it above the jz, and converting it to an lea, which leaves the flags register unaffected. In the PVOPS case, the code looks like: popl_cfi %eax # Error from the hypervisor lea 16(%esp),%esp # Add $16 before choosing fault path CFI_ADJUST_CFA_OFFSET -16 jz 5f addl $16,%esp # Incorrectly adjust %esp again jmp iret_exc It is possible unprivileged userspace applications to cause this behaviour, for example by loading an LDT code selector, then changing the code selector to be not-present. At this point, there is a race condition where it is possible for the hypervisor to return back to userspace from an interrupt, fault on its own iret, and inject a failsafe_callback into the kernel. This bug has been present since the introduction of Xen PVOPS support in commit 5ead97c84 (xen: Core Xen implementation), in 2.6.23. Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Cc: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-12-19introduce generic sys_sigaltstack(), switch x86 and um to itAl Viro1-1/+0
Conditional on CONFIG_GENERIC_SIGALTSTACK; architectures that do not select it are completely unaffected Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28x86, um: switch to generic fork/vfork/cloneAl Viro1-18/+0
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-19Merge commit 'v3.7-rc1' into stable/for-linus-3.7Konrad Rzeszutek Wilk1-28/+118
* commit 'v3.7-rc1': (10892 commits) Linux 3.7-rc1 x86, boot: Explicitly include autoconf.h for hostprogs perf: Fix UAPI fallout ARM: config: make sure that platforms are ordered by option string ARM: config: sort select statements alphanumerically UAPI: (Scripted) Disintegrate include/linux/byteorder UAPI: (Scripted) Disintegrate include/linux UAPI: Unexport linux/blk_types.h UAPI: Unexport part of linux/ppp-comp.h perf: Handle new rbtree implementation procfs: don't need a PATH_MAX allocation to hold a string representation of an int vfs: embed struct filename inside of names_cache allocation if possible audit: make audit_inode take struct filename vfs: make path_openat take a struct filename pointer vfs: turn do_path_lookup into wrapper around struct filename variant audit: allow audit code to satisfy getname requests from its names_list vfs: define struct filename and have getname() return it btrfs: Fix compilation with user namespace support enabled userns: Fix posix_acl_file_xattr_userns gid conversion userns: Properly print bluetooth socket uids ...
2012-10-19xen/x86: don't corrupt %eip when returning from a signal handlerDavid Vrabel1-3/+5
In 32 bit guests, if a userspace process has %eax == -ERESTARTSYS (-512) or -ERESTARTNOINTR (-513) when it is interrupted by an event /and/ the process has a pending signal then %eip (and %eax) are corrupted when returning to the main process after handling the signal. The application may then crash with SIGSEGV or a SIGILL or it may have subtly incorrect behaviour (depending on what instruction it returned to). The occurs because handle_signal() is incorrectly thinking that there is a system call that needs to restarted so it adjusts %eip and %eax to re-execute the system call instruction (even though user space had not done a system call). If %eax == -514 (-ERESTARTNOHAND (-514) or -ERESTART_RESTARTBLOCK (-516) then handle_signal() only corrupted %eax (by setting it to -EINTR). This may cause the application to crash or have incorrect behaviour. handle_signal() assumes that regs->orig_ax >= 0 means a system call so any kernel entry point that is not for a system call must push a negative value for orig_ax. For example, for physical interrupts on bare metal the inverse of the vector is pushed and page_fault() sets regs->orig_ax to -1, overwriting the hardware provided error code. xen_hypervisor_callback() was incorrectly pushing 0 for orig_ax instead of -1. Classic Xen kernels pushed %eax which works as %eax cannot be both non-negative and -RESTARTSYS (etc.), but using -1 is consistent with other non-system call entry points and avoids some of the tests in handle_signal(). There were similar bugs in xen_failsafe_callback() of both 32 and 64-bit guests. If the fault was corrected and the normal return path was used then 0 was incorrectly pushed as the value for orig_ax. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Jan Beulich <JBeulich@suse.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Cc: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-13Merge branch 'for-linus' of ↵Linus Torvalds1-19/+12
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull third pile of kernel_execve() patches from Al Viro: "The last bits of infrastructure for kernel_thread() et.al., with alpha/arm/x86 use of those. Plus sanitizing the asm glue and do_notify_resume() on alpha, fixing the "disabled irq while running task_work stuff" breakage there. At that point the rest of kernel_thread/kernel_execve/sys_execve work can be done independently for different architectures. The only pending bits that do depend on having all architectures converted are restrictred to fs/* and kernel/* - that'll obviously have to wait for the next cycle. I thought we'd have to wait for all of them done before we start eliminating the longjump-style insanity in kernel_execve(), but it turned out there's a very simple way to do that without flagday-style changes." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: alpha: switch to saner kernel_execve() semantics arm: switch to saner kernel_execve() semantics x86, um: convert to saner kernel_execve() semantics infrastructure for saner ret_from_kernel_thread semantics make sure that kernel_thread() callbacks call do_exit() themselves make sure that we always have a return path from kernel_execve() ppc: eeh_event should just use kthread_run() don't bother with kernel_thread/kernel_execve for launching linuxrc alpha: get rid of switch_stack argument of do_work_pending() alpha: don't bother passing switch_stack separately from regs alpha: take SIGPENDING/NOTIFY_RESUME loop into signal.c alpha: simplify TIF_NEED_RESCHED handling
2012-10-12x86, um: convert to saner kernel_execve() semanticsAl Viro1-19/+12
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12Merge branch 'for-linus' of ↵Linus Torvalds1-11/+6
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull pile 2 of execve and kernel_thread unification work from Al Viro: "Stuff in there: kernel_thread/kernel_execve/sys_execve conversions for several more architectures plus assorted signal fixes and cleanups. There'll be more (in particular, real fixes for the alpha do_notify_resume() irq mess)..." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (43 commits) alpha: don't open-code trace_report_syscall_{enter,exit} Uninclude linux/freezer.h m32r: trim masks avr32: trim masks tile: don't bother with SIGTRAP in setup_frame microblaze: don't bother with SIGTRAP in setup_rt_frame() mn10300: don't bother with SIGTRAP in setup_frame() frv: no need to raise SIGTRAP in setup_frame() x86: get rid of duplicate code in case of CONFIG_VM86 unicore32: remove pointless test h8300: trim _TIF_WORK_MASK parisc: decide whether to go to slow path (tracesys) based on thread flags parisc: don't bother looping in do_signal() parisc: fix double restarts bury the rest of TIF_IRET sanitize tsk_is_polling() bury _TIF_RESTORE_SIGMASK unicore32: unobfuscate _TIF_WORK_MASK mips: NOTIFY_RESUME is not needed in TIF masks mips: merge the identical "return from syscall" per-ABI code ... Conflicts: arch/arm/include/asm/thread_info.h
2012-10-10Merge branch 'for-linus' of ↵Linus Torvalds1-8/+18
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull generic execve() changes from Al Viro: "This introduces the generic kernel_thread() and kernel_execve() functions, and switches x86, arm, alpha, um and s390 over to them." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (26 commits) s390: convert to generic kernel_execve() s390: switch to generic kernel_thread() s390: fold kernel_thread_helper() into ret_from_fork() s390: fold execve_tail() into start_thread(), convert to generic sys_execve() um: switch to generic kernel_thread() x86, um/x86: switch to generic sys_execve and kernel_execve x86: split ret_from_fork alpha: introduce ret_from_kernel_execve(), switch to generic kernel_execve() alpha: switch to generic kernel_thread() alpha: switch to generic sys_execve() arm: get rid of execve wrapper, switch to generic execve() implementation arm: optimized current_pt_regs() arm: introduce ret_from_kernel_execve(), switch to generic kernel_execve() arm: split ret_from_fork, simplify kernel_thread() [based on patch by rmk] generic sys_execve() generic kernel_execve() new helper: current_pt_regs() preparation for generic kernel_thread() um: kill thread->forking um: let signal_delivered() do SIGTRAP on singlestepping into handler ...
2012-10-01Merge branch 'x86-smap-for-linus' of ↵Linus Torvalds1-0/+26
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/smap support from Ingo Molnar: "This adds support for the SMAP (Supervisor Mode Access Prevention) CPU feature on Intel CPUs: a hardware feature that prevents unintended user-space data access from kernel privileged code. It's turned on automatically when possible. This, in combination with SMEP, makes it even harder to exploit kernel bugs such as NULL pointer dereferences." Fix up trivial conflict in arch/x86/kernel/entry_64.S due to newly added includes right next to each other. * 'x86-smap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, smep, smap: Make the switching functions one-way x86, suspend: On wakeup always initialize cr4 and EFER x86-32: Start out eflags and cr4 clean x86, smap: Do not abuse the [f][x]rstor_checking() functions for user space x86-32, smap: Add STAC/CLAC instructions to 32-bit kernel entry x86, smap: Reduce the SMAP overhead for signal handling x86, smap: A page fault due to SMAP is an oops x86, smap: Turn on Supervisor Mode Access Prevention x86, smap: Add STAC and CLAC instructions to control user space access x86, uaccess: Merge prototypes for clear_user/__clear_user x86, smap: Add a header file with macros for STAC/CLAC x86, alternative: Add header guards to <asm/alternative-asm.h> x86, alternative: Use .pushsection/.popsection x86, smap: Add CR4 bit for SMAP x86-32, mm: The WP test should be done on a kernel page
2012-10-01x86: get rid of duplicate code in case of CONFIG_VM86Al Viro1-11/+6
no need to have the call of do_notify_resume() + checks around it duplicated for vm86 case - a bit of rearranging of ifdefs and we'll have a perfectly fine copy to jump back to. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30x86, um/x86: switch to generic sys_execve and kernel_execveAl Viro1-3/+8
32bit wrapper is lost on that; 64bit one is *not*, since we need to arrange for full pt_regs on stack when we call sys_execve() and we need to load callee-saved ones from there afterwards. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30x86: split ret_from_forkAl Viro1-5/+10
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-21x86-32, smap: Add STAC/CLAC instructions to 32-bit kernel entryH. Peter Anvin1-0/+26
The changes to entry_32.S got missed in checkin: 63bcff2a x86, smap: Add STAC and CLAC instructions to control user space access The resulting kernel was largely functional but SMAP protection could have been bypassed. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
2012-09-13ftrace/x86: Adjust x86 regs.ip as like as x86-64Masami Hiramatsu1-2/+1
Adjust x86 regs.ip to ip + MCOUNT_INSN_SIZE as like as on x86-64. This helps us to consolidate codes which use regs->ip on both of x86/x86-64. Link: http://lkml.kernel.org/r/20120905143100.10329.60109.stgit@localhost.localdomain Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31ftrace/x86: Remove function_trace_stop check from graph callerSteven Rostedt1-3/+0
The graph caller is called by the mcount callers, which already does the check against the function_trace_stop variable. No reason to check it again. Link: http://lkml.kernel.org/r/20120711195745.588538769@goodmis.org Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31ftrace/x86_32: Simplify parameter setup for ftrace_regs_callerUros Bizjak1-3/+2
The final position of the stack after saving regs and setting up the parameters for ftrace_regs_call, is the position of the pt_regs needed for the 4th parameter. Instead of saving it into a temporary reg and pushing the reg, simply push the stack pointer. Link: http://lkml.kernel.org/r/1342702344.12353.16.camel@gandalf.stny.rr.com Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-19ftrace/x86: Add save_regs for i386 function callsSteven Rostedt1-0/+68
Add saving full regs for function tracing on i386. The saving of regs was influenced by patches sent out by Masami Hiramatsu. Link: Link: http://lkml.kernel.org/r/20120711195745.379060003@goodmis.org Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-19ftrace/x86: Add separate function to save regsSteven Rostedt1-1/+3
Add a way to have different functions calling different trampolines. If a ftrace_ops wants regs saved on the return, then have only the functions with ops registered to save regs. Functions registered by other ops would not be affected, unless the functions overlap. If one ftrace_ops registered functions A, B and C and another ops registered fucntions to save regs on A, and D, then only functions A and D would be saving regs. Function B and C would work as normal. Although A is registered by both ops: normal and saves regs; this is fine as saving the regs is needed to satisfy one of the ops that calls it but the regs are ignored by the other ops function. x86_64 implements the full regs saving, and i386 just passes a NULL for regs to satisfy the ftrace_ops passing. Where an arch must supply both regs and ftrace_ops parameters, even if regs is just NULL. It is OK for an arch to pass NULL regs. All function trace users that require regs passing must add the flag FTRACE_OPS_FL_SAVE_REGS when registering the ftrace_ops. If the arch does not support saving regs then the ftrace_ops will fail to register. The flag FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED may be set that will prevent the ftrace_ops from failing to register. In this case, the handler may either check if regs is not NULL or check if ARCH_SUPPORTS_FTRACE_SAVE_REGS. If the arch supports passing regs it will set this macro and pass regs for ops that request them. All other archs will just pass NULL. Link: Link: http://lkml.kernel.org/r/20120711195745.107705970@goodmis.org Cc: Alexander van Heukelum <heukelum@fastmail.fm> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-19ftrace/x86_32: Push ftrace_ops in as 3rd parameter to function tracerSteven Rostedt1-0/+1
Add support of passing the current ftrace_ops into the 3rd parameter of the callback to the function tracer. Link: http://lkml.kernel.org/r/20120612225424.942411318@goodmis.org Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-01x86: get rid of calling do_notify_resume() when returning to kernel modeAl Viro1-3/+10
If we end up calling do_notify_resume() with !user_mode(refs), it does nothing (do_signal() explicitly bails out and we can't get there with TIF_NOTIFY_RESUME in such situations). Then we jump to resume_userspace_sig, which rechecks the same thing and bails out to resume_kernel, thus breaking the loop. It's easier and cheaper to check *before* calling do_notify_resume() and bail out to resume_kernel immediately. And kill the check in do_signal()... Note that on amd64 we can't get there with !user_mode() at all - asm glue takes care of that. Acked-and-reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-04-20x86, extable: Remove open-coded exception table entries in ↵H. Peter Anvin1-33/+14
arch/x86/kernel/entry_32.S Remove open-coded exception table entries in arch/x86/kernel/entry_32.S, and replace them with _ASM_EXTABLE() macros; this will allow us to change the format and type of the exception table entries. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: David Daney <david.daney@cavium.com> Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com