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| * | Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds2016-01-1113-74/+129
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu updates from Ingo Molnar: "The main changes in this cycle were: - Improved CPU ID handling code and related enhancements (Borislav Petkov) - RDRAND fix (Len Brown)" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Replace RDRAND forced-reseed with simple sanity check x86/MSR: Chop off lower 32-bit value x86/cpu: Fix MSR value truncation issue x86/cpu/amd, kvm: Satisfy guest kernel reads of IC_CFG MSR kvm: Add accessors for guest CPU's family, model, stepping x86/cpu: Unify CPU family, model, stepping calculation
| | * | x86: Replace RDRAND forced-reseed with simple sanity checkLen Brown2015-11-251-13/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | x86_init_rdrand() was added with 2 goals: 1. Sanity check that the built-in-self-test circuit on the Digital Random Number Generator (DRNG) is not complaining. As RDRAND HW self-checks on every invocation, this goal is achieved by simply invoking RDRAND and checking its return code. 2. Force a full re-seed of the random number generator. This was done out of paranoia to benefit the most un-sophisticated DRNG implementation conceivable in the architecture, an implementation that does not exist, and unlikely ever will. This worst-case full-re-seed is achieved by invoking a 64-bit RDRAND 8192 times. Unfortunately, this worst-case re-seed costs O(1,000us). Magnifying this cost, it is done from identify_cpu(), which is the synchronous critical path to bring a processor on-line -- repeated for every logical processor in the system at boot and resume from S3. As it is very expensive, and of highly dubious value, we delete the worst-case re-seed from the kernel. We keep the 1st goal -- sanity check the hardware, and mark it absent if it complains. This change reduces the cost of x86_init_rdrand() by a factor of 1,000x, to O(1us) from O(1,000us). Signed-off-by: Len Brown <len.brown@intel.com> Link: http://lkml.kernel.org/r/058618cc56ec6611171427ad7205e37e377aa8d4.1439738240.git.len.brown@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | x86/MSR: Chop off lower 32-bit valueBorislav Petkov2015-11-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sparse complains that the cast truncates the high bits. But here we really do know what we're doing and we need the lower 32 bits only as the @low argument. So make that explicit. Suggested-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1448273546-2567-7-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | x86/cpu: Fix MSR value truncation issueBorislav Petkov2015-11-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So sparse rightfully complains that the u64 MSR value we're writing into the STAR MSR, i.e. 0xc0000081, is being truncated: ./arch/x86/include/asm/msr.h:193:36: warning: cast truncates bits from constant value (23001000000000 becomes 0) because the actual value doesn't fit into the unsigned 32-bit quantity which are the @low and @high wrmsrl() parameters. This is not a problem, practically, because gcc is actually being smart enough here and does the right thing: .loc 3 87 0 xorl %esi, %esi # we needz a 32-bit zero movl $2293776, %edx # 0x00230010 == (__USER32_CS << 16) | __KERNEL_CS go into the high bits movl $-1073741695, %ecx # MSR_STAR, i.e., 0xc0000081 movl %esi, %eax # low order 32 bits in the MSR which are 0 #APP # 87 "./arch/x86/include/asm/msr.h" 1 wrmsr More specifically, MSR_STAR[31:0] is being set to 0. That field is reserved on Intel and on AMD it is 32-bit SYSCALL Target EIP. I'd strongly guess because Intel doesn't have SYSCALL in compat/legacy mode and we're using SYSENTER and INT80 there. And for compat syscalls in long mode we use CSTAR. So let's fix the sparse warning by writing SYSRET and SYSCALL CS and SS into the high 32-bit half of STAR and 0 in the low half explicitly. [ Actually, if we had to be precise, we would have to read what's in STAR[31:0] and write it back unchanged on Intel and write 0 on AMD. I guess the current writing to 0 is still ok since Intel can apparently stomach it. ] The resulting code is identical to what we have above: .loc 3 87 0 xorl %esi, %esi # tmp104 movl $2293776, %eax #, tmp103 movl $-1073741695, %ecx #, tmp102 movl %esi, %edx # tmp104, tmp104 ... wrmsr Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1448273546-2567-6-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | x86/cpu/amd, kvm: Satisfy guest kernel reads of IC_CFG MSRBorislav Petkov2015-11-243-2/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel accesses IC_CFG MSR (0xc0011021) on AMD because it checks whether the way access filter is enabled on some F15h models, and, if so, disables it. kvm doesn't handle that MSR access and complains about it, which can get really noisy in dmesg when one starts kvm guests all the time for testing. And it is useless anyway - guest kernel shouldn't be doing such changes anyway so tell it that that filter is disabled. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1448273546-2567-4-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | kvm: Add accessors for guest CPU's family, model, steppingBorislav Petkov2015-11-241-0/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Those give the family, model and stepping of the guest vcpu. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1448273546-2567-3-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | x86/cpu: Unify CPU family, model, stepping calculationBorislav Petkov2015-11-247-57/+61
| | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add generic functions which calc family, model and stepping from the CPUID_1.EAX leaf and stick them into the library we have. Rename those which do call CPUID with the prefix "x86_cpuid" as suggested by Paolo Bonzini. No functionality change. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1448273546-2567-2-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds2016-01-1137-269/+141
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Ingo Molnar: "The main changes in this cycle were: - code patching and cpu_has cleanups (Borislav Petkov) - paravirt cleanups (Juergen Gross) - TSC cleanup (Thomas Gleixner) - ptrace cleanup (Chen Gang)" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: arch/x86/kernel/ptrace.c: Remove unused arg_offs_table x86/mm: Align macro defines x86/cpu: Provide a config option to disable static_cpu_has x86/cpufeature: Remove unused and seldomly used cpu_has_xx macros x86/cpufeature: Cleanup get_cpu_cap() x86/cpufeature: Move some of the scattered feature bits to x86_capability x86/paravirt: Remove paravirt ops pmd_update[_defer] and pte_update_defer x86/paravirt: Remove unused pv_apic_ops structure x86/tsc: Remove unused tsc_pre_init() hook x86: Remove unused function cpu_has_ht_siblings() x86/paravirt: Kill some unused patching functions
| | * | arch/x86/kernel/ptrace.c: Remove unused arg_offs_tablechengang@emindsoft.com.cn2015-12-291-15/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The related warning from gcc 6.0: arch/x86/kernel/ptrace.c:127:18: warning: ‘arg_offs_table’ defined but not used [-Wunused-const-variable] static const int arg_offs_table[] = { ^~~~~~~~~~~~~~ Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Link: http://lkml.kernel.org/r/1451137798-28701-1-git-send-email-chengang@emindsoft.com.cn Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | x86/mm: Align macro definesBorislav Petkov2015-12-191-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Bring PAGE_{SHIFT,SIZE,MASK} to the same indentation level as the rest of the header. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1449480268-26583-1-git-send-email-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | x86/cpu: Provide a config option to disable static_cpu_hasBorislav Petkov2015-12-192-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This brings .text savings of about ~1.6K when building a tinyconfig. It is off by default so nothing changes for the default. Kconfig help text from Josh. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Link: http://lkml.kernel.org/r/1449481182-27541-5-git-send-email-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | x86/cpufeature: Remove unused and seldomly used cpu_has_xx macrosBorislav Petkov2015-12-1919-62/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Those are stupid and code should use static_cpu_has_safe() or boot_cpu_has() instead. Kill the least used and unused ones. The remaining ones need more careful inspection before a conversion can happen. On the TODO. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1449481182-27541-4-git-send-email-bp@alien8.de Cc: David Sterba <dsterba@suse.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Matt Mackall <mpm@selenic.com> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <jbacik@fb.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | x86/cpufeature: Cleanup get_cpu_cap()Borislav Petkov2015-12-194-28/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add an enum for the ->x86_capability array indices and cleanup get_cpu_cap() by killing some redundant local vars. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1449481182-27541-3-git-send-email-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | x86/cpufeature: Move some of the scattered feature bits to x86_capabilityBorislav Petkov2015-12-193-42/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Turn the CPUID leafs which are proper CPUID feature bit leafs into separate ->x86_capability words. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1449481182-27541-2-git-send-email-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | Merge branch 'linus' into x86/cleanupsThomas Gleixner2015-12-19101-1215/+3512
| | |\ \ | | | | | | | | | | | | | | | Pull in upstream changes so we can apply depending patches.
| | * | | x86/paravirt: Remove paravirt ops pmd_update[_defer] and pte_update_deferJuergen Gross2015-11-257-47/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pte_update_defer can be removed as it is always set to the same function as pte_update. So any usage of pte_update_defer() can be replaced by pte_update(). pmd_update and pmd_update_defer are always set to paravirt_nop, so they can just be nuked. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: jeremy@goop.org Cc: chrisw@sous-sol.org Cc: akataria@vmware.com Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xen.org Cc: konrad.wilk@oracle.com Cc: david.vrabel@citrix.com Cc: boris.ostrovsky@oracle.com Link: http://lkml.kernel.org/r/1447771879-1806-1-git-send-email-jgross@suse.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | x86/paravirt: Remove unused pv_apic_ops structureJuergen Gross2015-11-196-44/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The only member of that structure is startup_ipi_hook which is always set to paravirt_nop. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Cc: jeremy@goop.org Cc: chrisw@sous-sol.org Cc: akataria@vmware.com Cc: rusty@rustcorp.com.au Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xen.org Cc: konrad.wilk@oracle.com Cc: boris.ostrovsky@oracle.com Link: http://lkml.kernel.org/r/1447767872-16730-1-git-send-email-jgross@suse.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | x86/tsc: Remove unused tsc_pre_init() hookThomas Gleixner2015-11-193-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No more users. Remove it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@suse.de>
| | * | | x86: Remove unused function cpu_has_ht_siblings()Juergen Gross2015-11-171-9/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is used nowhere. Signed-off-by: Juergen Gross <jgross@suse.com> Link: http://lkml.kernel.org/r/1447761943-770-1-git-send-email-jgross@suse.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | x86/paravirt: Kill some unused patching functionsBorislav Petkov2015-11-072-14/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | paravirt_patch_ignore() is completely unused and paravirt_patch_nop() doesn't do a whole lot. Remove them both. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1446542329-32037-1-git-send-email-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds2016-01-1126-240/+190
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "The main changes in this cycle were: - vDSO and asm entry improvements (Andy Lutomirski) - Xen paravirt entry enhancements (Boris Ostrovsky) - asm entry labels enhancement (Borislav Petkov) - and other misc changes (Thomas Gleixner, me)" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vsdo: Fix build on PARAVIRT_CLOCK=y, KVM_GUEST=n Revert "x86/kvm: On KVM re-enable (e.g. after suspend), update clocks" x86/entry/64_compat: Make labels local x86/platform/uv: Include clocksource.h for clocksource_touch_watchdog() x86/vdso: Enable vdso pvclock access on all vdso variants x86/vdso: Remove pvclock fixmap machinery x86/vdso: Get pvclock data from the vvar VMA instead of the fixmap x86, vdso, pvclock: Simplify and speed up the vdso pvclock reader x86/kvm: On KVM re-enable (e.g. after suspend), update clocks x86/entry/64: Bypass enter_from_user_mode on non-context-tracking boots x86/asm: Add asm macros for static keys/jump labels x86/asm: Error out if asm/jump_label.h is included inappropriately context_tracking: Switch to new static_branch API x86/entry, x86/paravirt: Remove the unused usergs_sysret32 PV op x86/paravirt: Remove the unused irq_enable_sysexit pv op x86/xen: Avoid fast syscall path for Xen PV guests
| | * | | | x86/vsdo: Fix build on PARAVIRT_CLOCK=y, KVM_GUEST=nAndy Lutomirski2016-01-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | arch/x86/built-in.o: In function `arch_setup_additional_pages': (.text+0x587): undefined reference to `pvclock_pvti_cpu0_va' KVM_GUEST selects PARAVIRT_CLOCK, so we can make pvclock_pvti_cpu0_va depend on KVM_GUEST. Signed-off-by: Andy Lutomirski <luto@kernel.org> Tested-by: Borislav Petkov <bp@alien8.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/444d38a9bcba832685740ea1401b569861d09a72.1451446564.git.luto@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | Revert "x86/kvm: On KVM re-enable (e.g. after suspend), update clocks"Thomas Gleixner2015-12-231-3/+72
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 677a73a9aa54. This patch was not meant to be merged and has issues. Revert it. Requested-by: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | x86/entry/64_compat: Make labels localBorislav Petkov2015-12-141-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ... so that they don't appear as symbols in the final ELF. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1449916077-6506-1-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/platform/uv: Include clocksource.h for clocksource_touch_watchdog()Ingo Molnar2015-12-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This build failure triggers on 64-bit allmodconfig: arch/x86/platform/uv/uv_nmi.c:493:2: error: implicit declaration of function ‘clocksource_touch_watchdog’ [-Werror=implicit-function-declaration] which is caused by recent changes exposing a missing clocksource.h include in uv_nmi.c: cc1e24fdb064 x86/vdso: Remove pvclock fixmap machinery this file got clocksource.h indirectly via fixmap.h - that stealth route of header inclusion is now gone. Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/vdso: Enable vdso pvclock access on all vdso variantsAndy Lutomirski2015-12-111-51/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that pvclock doesn't require access to the fixmap, all vdso variants can use it. The kernel side isn't wired up for 32-bit kernels yet, but this covers 32-bit and x32 userspace on 64-bit kernels. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/a7ef693b7a4c88dd2173dc1d4bf6bc27023626eb.1449702533.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/vdso: Remove pvclock fixmap machineryAndy Lutomirski2015-12-116-41/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/4933029991103ae44672c82b97a20035f5c1fe4f.1449702533.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/vdso: Get pvclock data from the vvar VMA instead of the fixmapAndy Lutomirski2015-12-117-13/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/9d37826fdc7e2d2809efe31d5345f97186859284.1449702533.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86, vdso, pvclock: Simplify and speed up the vdso pvclock readerAndy Lutomirski2015-12-111-35/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The pvclock vdso code was too abstracted to understand easily and excessively paranoid. Simplify it for a huge speedup. This opens the door for additional simplifications, as the vdso no longer accesses the pvti for any vcpu other than vcpu 0. Before, vclock_gettime using kvm-clock took about 45ns on my machine. With this change, it takes 29ns, which is almost as fast as the pure TSC implementation. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/6b51dcc41f1b101f963945c5ec7093d72bdac429.1449702533.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/kvm: On KVM re-enable (e.g. after suspend), update clocksAndy Lutomirski2015-12-111-72/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This gets rid of the "did TSC go backwards" logic and just updates all clocks. It should work better (no more disabling of fast timing) and more reliably (all of the clocks are actually updated). Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/861716d768a1da6d1fd257b7972f8df13baf7f85.1449702533.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/entry/64: Bypass enter_from_user_mode on non-context-tracking bootsAndy Lutomirski2015-11-242-6/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On CONFIG_CONTEXT_TRACKING kernels that have context tracking disabled at runtime (which includes most distro kernels), we still have the overhead of a call to enter_from_user_mode in interrupt and exception entries. If jump labels are available, this uses the jump label infrastructure to skip the call. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/73ee804fff48cd8c66b65b724f9f728a11a8c686.1447361906.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/asm: Add asm macros for static keys/jump labelsAndy Lutomirski2015-11-241-8/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unfortunately, we can only do this if HAVE_JUMP_LABEL. In principle, we could do some serious surgery on the core jump label infrastructure to keep the patch infrastructure available on x86 on all builds, but that's probably not worth it. Implementing the macros using a conditional branch as a fallback seems like a bad idea: we'd have to clobber flags. This limitation can't cause silent failures -- trying to include asm/jump_label.h at all on a non-HAVE_JUMP_LABEL kernel will error out. The macro's users are responsible for handling this issue themselves. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/63aa45c4b692e8469e1876d6ccbb5da707972990.1447361906.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/asm: Error out if asm/jump_label.h is included inappropriatelyAndy Lutomirski2015-11-241-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rather than potentially generating incorrect code on a non-HAVE_JUMP_LABEL kernel if someone includes asm/jump_label.h, error out. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/99407f0ac7fa3ab03a3d31ce076d47b5c2f44795.1447361906.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | Merge branch 'x86/urgent' into x86/asm, to pick up dependent fixesIngo Molnar2015-11-243-3/+19
| | |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/entry, x86/paravirt: Remove the unused usergs_sysret32 PV opBoris Ostrovsky2015-11-237-48/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As result of commit "x86/xen: Avoid fast syscall path for Xen PV guests", usergs_sysret32 pv op is not called by Xen PV guests anymore and since they were the only ones who used it we can safely remove it. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: david.vrabel@citrix.com Cc: konrad.wilk@oracle.com Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1447970147-1733-4-git-send-email-boris.ostrovsky@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/paravirt: Remove the unused irq_enable_sysexit pv opBoris Ostrovsky2015-11-2310-55/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As result of commit "x86/xen: Avoid fast syscall path for Xen PV guests", the irq_enable_sysexit pv op is not called by Xen PV guests anymore and since they were the only ones who used it we can safely remove it. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: david.vrabel@citrix.com Cc: konrad.wilk@oracle.com Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1447970147-1733-3-git-send-email-boris.ostrovsky@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/xen: Avoid fast syscall path for Xen PV guestsBoris Ostrovsky2015-11-234-7/+13
| | | |_|_|/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After 32-bit syscall rewrite, and specifically after commit: 5f310f739b4c ("x86/entry/32: Re-implement SYSENTER using the new C path") ... the stack frame that is passed to xen_sysexit is no longer a "standard" one (i.e. it's not pt_regs). Since we end up calling xen_iret from xen_sysexit we don't need to fix up the stack and instead follow entry_SYSENTER_32's IRET path directly to xen_iret. We can do the same thing for compat mode even though stack does not need to be fixed. This will allow us to drop usergs_sysret32 paravirt op (in the subsequent patch) Suggested-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: david.vrabel@citrix.com Cc: konrad.wilk@oracle.com Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1447970147-1733-2-git-send-email-boris.ostrovsky@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | Merge branch 'x86-apic-for-linus' of ↵Linus Torvalds2016-01-1119-35/+172
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic updates from Ingo Molnar: "The main changes in this cycle were: - introduce optimized single IPI sending methods on modern APICs (Linus Torvalds, Thomas Gleixner) - kexec/crash APIC handling fixes and enhancements (Hidehiro Kawai) - extend lapic vector saving/restoring to the CMCI (MCE) vector as well (Juergen Gross) - various fixes and enhancements (Jake Oshins, Len Brown)" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) x86/irq: Export functions to allow MSI domains in modules Documentation: Document kernel.panic_on_io_nmi sysctl x86/nmi: Save regs in crash dump on external NMI x86/apic: Introduce apic_extnmi command line parameter kexec: Fix race between panic() and crash_kexec() panic, x86: Allow CPUs to save registers even if looping in NMI context panic, x86: Fix re-entrance problem due to panic on NMI x86/apic: Fix the saving and restoring of lapic vectors during suspend/resume x86/smpboot: Re-enable init_udelay=0 by default on modern CPUs x86/smp: Remove single IPI wrapper x86/apic: Use default send single IPI wrapper x86/apic: Provide default send single IPI wrapper x86/apic: Implement single IPI for apic_noop x86/apic: Wire up single IPI for apic_numachip x86/apic: Wire up single IPI for x2apic_uv x86/apic: Implement single IPI for x2apic_phys x86/apic: Wire up single IPI for bigsmp_apic x86/apic: Remove pointless indirections from bigsmp_apic x86/apic: Wire up single IPI for apic_physflat x86/apic: Remove pointless indirections from apic_physflat ...
| | * | | | | x86/irq: Export functions to allow MSI domains in modulesJake Oshins2015-12-203-3/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Linux kernel already has the concept of IRQ domain, wherein a component can expose a set of IRQs which are managed by a particular interrupt controller chip or other subsystem. The PCI driver exposes the notion of an IRQ domain for Message-Signaled Interrupts (MSI) from PCI Express devices. This patch exposes the functions which are necessary for creating a MSI IRQ domain within a module. [ tglx: Split it into x86 and core irq parts ] Signed-off-by: Jake Oshins <jakeo@microsoft.com> Cc: gregkh@linuxfoundation.org Cc: kys@microsoft.com Cc: devel@linuxdriverproject.org Cc: olaf@aepfle.de Cc: apw@canonical.com Cc: vkuznets@redhat.com Cc: haiyangz@microsoft.com Cc: marc.zyngier@arm.com Cc: bhelgaas@google.com Link: http://lkml.kernel.org/r/1449769983-12948-4-git-send-email-jakeo@microsoft.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | | x86/nmi: Save regs in crash dump on external NMIHidehiro Kawai2015-12-193-9/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now, multiple CPUs can receive an external NMI simultaneously by specifying the "apic_extnmi=all" command line parameter. When we take a crash dump by using external NMI with this option, we fail to save registers into the crash dump. This happens as follows: CPU 0 CPU 1 ================================ ============================= receive an external NMI default_do_nmi() receive an external NMI spin_lock(&nmi_reason_lock) default_do_nmi() io_check_error() spin_lock(&nmi_reason_lock) panic() busy loop ... kdump_nmi_shootdown_cpus() issue NMI IPI -----------> blocked until IRET busy loop... Here, since CPU 1 is in NMI context, an additional NMI from CPU 0 remains unhandled until CPU 1 IRETs. However, CPU 1 will never execute IRET so the NMI is not handled and the callback function to save registers is never called. To solve this issue, we check if the IPI for crash dumping was issued while waiting for nmi_reason_lock to be released, and if so, call its callback function directly. If the IPI is not issued (e.g. kdump is disabled), the actual behavior doesn't change. Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: kexec@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stefan Lippers-Hollmann <s.l-h@gmx.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: x86-ml <x86@kernel.org> Link: http://lkml.kernel.org/r/20151210065245.4587.39316.stgit@softrs Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | | x86/apic: Introduce apic_extnmi command line parameterHidehiro Kawai2015-12-192-2/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces a command line parameter apic_extnmi: apic_extnmi=( bsp|all|none ) The default value is "bsp" and this is the current behavior: only the Boot-Strapping Processor receives an external NMI. "all" allows external NMIs to be broadcast to all CPUs. This would raise the success rate of panic on NMI when BSP hangs in NMI context or the external NMI is swallowed by other NMI handlers on the BSP. If you specify "none", no CPUs receive external NMIs. This is useful for the dump capture kernel so that it cannot be shot down by accidentally pressing the external NMI button (on platforms which have it) while saving a crash dump. Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Bandan Das <bsd@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: kexec@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: "Maciej W. Rozycki" <macro@linux-mips.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: x86-ml <x86@kernel.org> Link: http://lkml.kernel.org/r/20151210014632.25437.43778.stgit@softrs Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | | panic, x86: Allow CPUs to save registers even if looping in NMI contextHidehiro Kawai2015-12-192-3/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, kdump_nmi_shootdown_cpus(), a subroutine of crash_kexec(), sends an NMI IPI to CPUs which haven't called panic() to stop them, save their register information and do some cleanups for crash dumping. However, if such a CPU is infinitely looping in NMI context, we fail to save its register information into the crash dump. For example, this can happen when unknown NMIs are broadcast to all CPUs as follows: CPU 0 CPU 1 =========================== ========================== receive an unknown NMI unknown_nmi_error() panic() receive an unknown NMI spin_trylock(&panic_lock) unknown_nmi_error() crash_kexec() panic() spin_trylock(&panic_lock) panic_smp_self_stop() infinite loop kdump_nmi_shootdown_cpus() issue NMI IPI -----------> blocked until IRET infinite loop... Here, since CPU 1 is in NMI context, the second NMI from CPU 0 is blocked until CPU 1 executes IRET. However, CPU 1 never executes IRET, so the NMI is not handled and the callback function to save registers is never called. In practice, this can happen on some servers which broadcast NMIs to all CPUs when the NMI button is pushed. To save registers in this case, we need to: a) Return from NMI handler instead of looping infinitely or b) Call the callback function directly from the infinite loop Inherently, a) is risky because NMI is also used to prevent corrupted data from being propagated to devices. So, we chose b). This patch does the following: 1. Move the infinite looping of CPUs which haven't called panic() in NMI context (actually done by panic_smp_self_stop()) outside of panic() to enable us to refer pt_regs. Please note that panic_smp_self_stop() is still used for normal context. 2. Call a callback of kdump_nmi_shootdown_cpus() directly to save registers and do some cleanups after setting waiting_for_crash_ipi which is used for counting down the number of CPUs which handled the callback Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Aaron Tomlin <atomlin@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <dahi@linux.vnet.ibm.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Javi Merino <javi.merino@arm.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: kexec@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: lkml <linux-kernel@vger.kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Seth Jennings <sjenning@redhat.com> Cc: Stefan Lippers-Hollmann <s.l-h@gmx.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ulrich Obergfell <uobergfe@redhat.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Link: http://lkml.kernel.org/r/20151210014628.25437.75256.stgit@softrs [ Cleanup comments, fixup formatting. ] Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | | panic, x86: Fix re-entrance problem due to panic on NMIHidehiro Kawai2015-12-191-4/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If panic on NMI happens just after panic() on the same CPU, panic() is recursively called. Kernel stalls, as a result, after failing to acquire panic_lock. To avoid this problem, don't call panic() in NMI context if we've already entered panic(). For that, introduce nmi_panic() macro to reduce code duplication. In the case of panic on NMI, don't return from NMI handlers if another CPU already panicked. Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Aaron Tomlin <atomlin@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: David Hildenbrand <dahi@linux.vnet.ibm.com> Cc: Don Zickus <dzickus@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Javi Merino <javi.merino@arm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: kexec@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: lkml <linux-kernel@vger.kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Seth Jennings <sjenning@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ulrich Obergfell <uobergfe@redhat.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Link: http://lkml.kernel.org/r/20151210014626.25437.13302.stgit@softrs [ Cleanup comments, fixup formatting. ] Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | | Merge branch 'linus' into x86/apicThomas Gleixner2015-12-19100-1211/+3507
| | |\ \ \ \ \ | | | | |_|_|/ | | | |/| | | | | | | | | | Pull in update changes so we can apply conflicting patches
| | * | | | | x86/apic: Fix the saving and restoring of lapic vectors during suspend/resumeJuergen Gross2015-11-241-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Saving and restoring lapic vectors in lapic_suspend() and lapic_resume() is not consistent: the thmr vector saving is guarded by a different config option than the restore part. The cmci vector isn't handled at all. Those inconsistencies are not very critical, as the missing cmci vector will be set via mce resume handling, the wrong config option used for restoring the thmr vector can't be configured differently than the one which should be used. Nevertheless correct the thmr vector restore and add cmci vector handling. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1448276364-31334-1-git-send-email-jgross@suse.com [ Minor code edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/smpboot: Re-enable init_udelay=0 by default on modern CPUsLen Brown2015-11-231-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a Linux-4.3 corner case performance regression, introduced by commit: f1ccd249319e ("x86/smpboot: Fix cpu_init_udelay=10000 corner case boot parameter misbehavior") which allowed the cmdline "cpu_init_udelay=" to work with all values, including the default of 10000. But in setting the default of 10000, it over-rode the code stat sets the delay 0 on modern processors. Also, tidy up use of INT/UINT. Reported-by: Shane <shrybman@teksavvy.com> Signed-off-by: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dparsons@brightdsl.net Link: http://lkml.kernel.org/r/9082eb809ef40dad02db714759c7aaf618c518d4.1448232494.git.len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/smp: Remove single IPI wrapperThomas Gleixner2015-11-051-14/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All APIC implementation have send_IPI now. Remove the conditional in the calling code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Borislav Petkov <bp@alien.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Travis <travis@sgi.com> Cc: Daniel J Blueman <daniel@numascale.com> Link: http://lkml.kernel.org/r/20151104220849.807817097@linutronix.de
| | * | | | | x86/apic: Use default send single IPI wrapperThomas Gleixner2015-11-052-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Wire up the default_send_IPI_single() wrapper to the last holdouts. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Borislav Petkov <bp@alien.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Travis <travis@sgi.com> Cc: Daniel J Blueman <daniel@numascale.com> Link: http://lkml.kernel.org/r/20151104220849.711224890@linutronix.de
| | * | | | | x86/apic: Provide default send single IPI wrapperThomas Gleixner2015-11-052-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of doing the wrapping in the smp code we can provide a default wrapper for those APICs which insist on cpumasks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Borislav Petkov <bp@alien.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Travis <travis@sgi.com> Cc: Daniel J Blueman <daniel@numascale.com> Link: http://lkml.kernel.org/r/20151104220849.631111846@linutronix.de
| | * | | | | x86/apic: Implement single IPI for apic_noopThomas Gleixner2015-11-051-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Borislav Petkov <bp@alien.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Travis <travis@sgi.com> Cc: Daniel J Blueman <daniel@numascale.com> Link: http://lkml.kernel.org/r/20151104220849.455429817@linutronix.de
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