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2018-01-28Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 retpoline fixlet from Thomas Gleixner: "Remove the ESP/RSP thunks for retpoline as they cannot ever work. Get rid of them before they show up in a release" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/retpoline: Remove the esp/rsp thunk
2018-01-28Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A set of small fixes for 4.15: - Fix vmapped stack synchronization on systems with 4-level paging and a large amount of memory caused by a missing 5-level folding which made the pgd synchronization logic to fail and causing double faults. - Add a missing sanity check in the vmalloc_fault() logic on 5-level paging systems. - Bring back protection against accessing a freed initrd in the microcode loader which was lost by a wrong merge conflict resolution. - Extend the Broadwell micro code loading sanity check. - Add a missing ENDPROC annotation in ftrace assembly code which makes ORC unhappy. - Prevent loading the AMD power module on !AMD platforms. The load itself is uncritical, but an unload attempt results in a kernel crash. - Update Peter Anvins role in the MAINTAINERS file" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/ftrace: Add one more ENDPROC annotation x86: Mark hpa as a "Designated Reviewer" for the time being x86/mm/64: Tighten up vmalloc_fault() sanity checks on 5-level kernels x86/mm/64: Fix vmapped stack syncing on very-large-memory 4-level systems x86/microcode: Fix again accessing initrd after having been freed x86/microcode/intel: Extend BDW late-loading further with LLC size check perf/x86/amd/power: Do not load AMD power module on !AMD platforms
2018-01-28Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "Four patches which all address lock inversions and deadlocks in the perf core code and the Intel debug store" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: Fix perf,x86,cpuhp deadlock perf/core: Fix ctx::mutex deadlock perf/core: Fix another perf,trace,cpuhp lock inversion perf/core: Fix lock inversion between perf,trace,cpuhp
2018-01-28x86/ftrace: Add one more ENDPROC annotationJosh Poimboeuf
When ORC support was added for the ftrace_64.S code, an ENDPROC for function_hook() was missed. This results in the following warning: arch/x86/kernel/ftrace_64.o: warning: objtool: .entry.text+0x0: unreachable instruction Fixes: e2ac83d74a4d ("x86/ftrace: Fix ORC unwinding from ftrace handlers") Reported-by: Steven Rostedt <rostedt@goodmis.org> Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/20180128022150.dqierscqmt3uwwsr@treble
2018-01-26x86/mm/64: Tighten up vmalloc_fault() sanity checks on 5-level kernelsAndy Lutomirski
On a 5-level kernel, if a non-init mm has a top-level entry, it needs to match init_mm's, but the vmalloc_fault() code skipped over the BUG_ON() that would have checked it. While we're at it, get rid of the rather confusing 4-level folded "pgd" logic. Cleans-up: b50858ce3e2a ("x86/mm/vmalloc: Add 5-level paging support") Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Neil Berrington <neil.berrington@datacore.com> Link: https://lkml.kernel.org/r/2ae598f8c279b0a29baf75df207e6f2fdddc0a1b.1516914529.git.luto@kernel.org
2018-01-26x86/mm/64: Fix vmapped stack syncing on very-large-memory 4-level systemsAndy Lutomirski
Neil Berrington reported a double-fault on a VM with 768GB of RAM that uses large amounts of vmalloc space with PTI enabled. The cause is that load_new_mm_cr3() was never fixed to take the 5-level pgd folding code into account, so, on a 4-level kernel, the pgd synchronization logic compiles away to exactly nothing. Interestingly, the problem doesn't trigger with nopti. I assume this is because the kernel is mapped with global pages if we boot with nopti. The sequence of operations when we create a new task is that we first load its mm while still running on the old stack (which crashes if the old stack is unmapped in the new mm unless the TLB saves us), then we call prepare_switch_to(), and then we switch to the new stack. prepare_switch_to() pokes the new stack directly, which will populate the mapping through vmalloc_fault(). I assume that we're getting lucky on non-PTI systems -- the old stack's TLB entry stays alive long enough to make it all the way through prepare_switch_to() and switch_to() so that we make it to a valid stack. Fixes: b50858ce3e2a ("x86/mm/vmalloc: Add 5-level paging support") Reported-and-tested-by: Neil Berrington <neil.berrington@datacore.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: stable@vger.kernel.org Cc: Dave Hansen <dave.hansen@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: https://lkml.kernel.org/r/346541c56caed61abbe693d7d2742b4a380c5001.1516914529.git.luto@kernel.org
2018-01-25perf/x86: Fix perf,x86,cpuhp deadlockPeter Zijlstra
More lockdep gifts, a 5-way lockup race: perf_event_create_kernel_counter() perf_event_alloc() perf_try_init_event() x86_pmu_event_init() __x86_pmu_event_init() x86_reserve_hardware() #0 mutex_lock(&pmc_reserve_mutex); reserve_ds_buffer() #1 get_online_cpus() perf_event_release_kernel() _free_event() hw_perf_event_destroy() x86_release_hardware() #0 mutex_lock(&pmc_reserve_mutex) release_ds_buffer() #1 get_online_cpus() #1 do_cpu_up() perf_event_init_cpu() #2 mutex_lock(&pmus_lock) #3 mutex_lock(&ctx->mutex) sys_perf_event_open() mutex_lock_double() #3 mutex_lock(ctx->mutex) #4 mutex_lock_nested(ctx->mutex, 1); perf_try_init_event() #4 mutex_lock_nested(ctx->mutex, 1) x86_pmu_event_init() intel_pmu_hw_config() x86_add_exclusive() #0 mutex_lock(&pmc_reserve_mutex) Fix it by using ordering constructs instead of locking. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-24Merge tag 'trace-v4.15-rc9' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "With the new ORC unwinder, ftrace stack tracing became disfunctional. One was that ORC didn't know how to handle the ftrace callbacks in general (which Josh fixed). The other was that ORC would just bail if it hit a dynamically allocated trampoline. Which means all ftrace stack tracing that happens from the function tracer would produce no results (that includes killing the max stack size tracer). I added a check to the ORC unwinder to see if the trampoline belonged to ftrace, and if it did, use the orc entry of the static trampoline that was used to create the dynamic one (it would be identical). Finally, I noticed that the skip values of the stack tracing were out of whack. I went through and fixed them up" * tag 'trace-v4.15-rc9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Update stack trace skipping for ORC unwinder ftrace, orc, x86: Handle ftrace dynamically allocated trampolines x86/ftrace: Fix ORC unwinding from ftrace handlers
2018-01-24x86/microcode: Fix again accessing initrd after having been freedBorislav Petkov
Commit 24c2503255d3 ("x86/microcode: Do not access the initrd after it has been freed") fixed attempts to access initrd from the microcode loader after it has been freed. However, a similar KASAN warning was reported (stack trace edited): smpboot: Booting Node 0 Processor 1 APIC 0x11 ================================================================== BUG: KASAN: use-after-free in find_cpio_data+0x9b5/0xa50 Read of size 1 at addr ffff880035ffd000 by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.14.8-slack #7 Hardware name: System manufacturer System Product Name/A88X-PLUS, BIOS 3003 03/10/2016 Call Trace: dump_stack print_address_description kasan_report ? find_cpio_data __asan_report_load1_noabort find_cpio_data find_microcode_in_initrd __load_ucode_amd load_ucode_amd_ap load_ucode_ap After some investigation, it turned out that a merge was done using the wrong side to resolve, leading to picking up the previous state, before the 24c2503255d3 fix. Therefore the Fixes tag below contains a merge commit. Revert the mismerge by catching the save_microcode_in_initrd_amd() retval and thus letting the function exit with the last return statement so that initrd_gone can be set to true. Fixes: f26483eaedec ("Merge branch 'x86/urgent' into x86/microcode, to resolve conflicts") Reported-by: <higuita@gmx.net> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=198295 Link: https://lkml.kernel.org/r/20180123104133.918-2-bp@alien8.de
2018-01-24x86/microcode/intel: Extend BDW late-loading further with LLC size checkJia Zhang
Commit b94b73733171 ("x86/microcode/intel: Extend BDW late-loading with a revision check") reduced the impact of erratum BDF90 for Broadwell model 79. The impact can be reduced further by checking the size of the last level cache portion per core. Tony: "The erratum says the problem only occurs on the large-cache SKUs. So we only need to avoid the update if we are on a big cache SKU that is also running old microcode." For more details, see erratum BDF90 in document #334165 (Intel Xeon Processor E7-8800/4800 v4 Product Family Specification Update) from September 2017. Fixes: b94b73733171 ("x86/microcode/intel: Extend BDW late-loading with a revision check") Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Tony Luck <tony.luck@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1516321542-31161-1-git-send-email-zhang.jia@linux.alibaba.com
2018-01-24perf/x86/amd/power: Do not load AMD power module on !AMD platformsXiao Liang
The AMD power module can be loaded on non AMD platforms, but unload fails with the following Oops: BUG: unable to handle kernel NULL pointer dereference at (null) IP: __list_del_entry_valid+0x29/0x90 Call Trace: perf_pmu_unregister+0x25/0xf0 amd_power_pmu_exit+0x1c/0xd23 [power] SyS_delete_module+0x1a8/0x2b0 ? exit_to_usermode_loop+0x8f/0xb0 entry_SYSCALL_64_fastpath+0x20/0x83 Return -ENODEV instead of 0 from the module init function if the CPU does not match. Fixes: c7ab62bfbe0e ("perf/x86/amd/power: Add AMD accumulated power reporting mechanism") Signed-off-by: Xiao Liang <xiliang@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180122061252.6394-1-xiliang@redhat.com
2018-01-24x86/retpoline: Remove the esp/rsp thunkWaiman Long
It doesn't make sense to have an indirect call thunk with esp/rsp as retpoline code won't work correctly with the stack pointer register. Removing it will help compiler writers to catch error in case such a thunk call is emitted incorrectly. Fixes: 76b043848fd2 ("x86/retpoline: Add initial retpoline support") Suggested-by: Jeff Law <law@redhat.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Kees Cook <keescook@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: https://lkml.kernel.org/r/1516658974-27852-1-git-send-email-longman@redhat.com
2018-01-23ftrace, orc, x86: Handle ftrace dynamically allocated trampolinesSteven Rostedt (VMware)
The function tracer can create a dynamically allocated trampoline that is called by the function mcount or fentry hook that is used to call the function callback that is registered. The problem is that the orc undwinder will bail if it encounters one of these trampolines. This breaks the stack trace of function callbacks, which include the stack tracer and setting the stack trace for individual functions. Since these dynamic trampolines are basically copies of the static ftrace trampolines defined in ftrace_*.S, we do not need to create new orc entries for the dynamic trampolines. Finding the return address on the stack will be identical as the functions that were copied to create the dynamic trampolines. When encountering a ftrace dynamic trampoline, we can just use the orc entry of the ftrace static function that was copied for that trampoline. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23Merge tag 'pci-v4.15-fixes-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI fix from Bjorn Helgaas: "Fix AMD regression due to not re-enabling the big window on resume (Christian König)" * tag 'pci-v4.15-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: x86/PCI: Enable AMD 64-bit window on resume
2018-01-23x86/ftrace: Fix ORC unwinding from ftrace handlersJosh Poimboeuf
Steven Rostedt discovered that the ftrace stack tracer is broken when it's used with the ORC unwinder. The problem is that objtool is instructed by the Makefile to ignore the ftrace_64.S code, so it doesn't generate any ORC data for it. Fix it by making the asm code objtool-friendly: - Objtool doesn't like the fact that save_mcount_regs pushes RBP at the beginning, but it's never restored (directly, at least). So just skip the original RBP push, which is only needed for frame pointers anyway. - Annotate some functions as normal callable functions with ENTRY/ENDPROC. - Add an empty unwind hint to return_to_handler(). The return address isn't on the stack, so there's nothing ORC can do there. It will just punt in the unlikely case it tries to unwind from that code. With all that fixed, remove the OBJECT_FILES_NON_STANDARD Makefile annotation so objtool can read the file. Link: http://lkml.kernel.org/r/20180123040746.ih4ep3tk4pbjvg7c@treble Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-21Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 pti fixes from Thomas Gleixner: "A small set of fixes for the meltdown/spectre mitigations: - Make kprobes aware of retpolines to prevent probes in the retpoline thunks. - Make the machine check exception speculation protected. MCE used to issue an indirect call directly from the ASM entry code. Convert that to a direct call into a C-function and issue the indirect call from there so the compiler can add the retpoline protection, - Make the vmexit_fill_RSB() assembly less stupid - Fix a typo in the PTI documentation" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/retpoline: Optimize inline assembler for vmexit_fill_RSB x86/pti: Document fix wrong index kprobes/x86: Disable optimizing on the function jumps to indirect thunk kprobes/x86: Blacklist indirect thunk functions for kprobes retpoline: Introduce start/end markers of indirect thunk x86/mce: Make machine check speculation protected
2018-01-21Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 kexec fix from Thomas Gleixner: "A single fix for the WBINVD issue introduced by the SME support which causes kexec fails on non AMD/SME capable CPUs. Issue WBINVD only when the CPU has SME and avoid doing so in a loop" [ Side note: this patch fixes the problem, but it isn't entirely clear why it is required. The wbinvd should just work regardless, but there seems to be some system - as opposed to CPU - issue, since the wbinvd causes more problems later in the shutdown sequence, but wbinvd instructions while the system is still active are not problematic. Possibly some SMI or pending machine check issue on the affected system ] * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Rework wbinvd, hlt operation in stop_this_cpu()
2018-01-20x86: Use __nostackprotect for sme_encrypt_kernelLaura Abbott
Commit bacf6b499e11 ("x86/mm: Use a struct to reduce parameters for SME PGD mapping") moved some parameters into a structure. The structure was large enough to trigger the stack protection canary in sme_encrypt_kernel which doesn't work this early, causing reboots. Mark sme_encrypt_kernel appropriately to not use the canary. Fixes: bacf6b499e11 ("x86/mm: Use a struct to reduce parameters for SME PGD mapping") Signed-off-by: Laura Abbott <labbott@redhat.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-20Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Radim Krčmář: "ARM: - fix incorrect huge page mappings on systems using the contiguous hint for hugetlbfs - support alternative GICv4 init sequence - correctly implement the ARM SMCC for HVC and SMC handling PPC: - add KVM IOCTL for reporting vulnerability and workaround status s390: - provide userspace interface for branch prediction changes in firmware x86: - use correct macros for bits" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: s390: wire up bpb feature KVM: PPC: Book3S: Provide information about hardware/firmware CVE workarounds KVM/x86: Fix wrong macro references of X86_CR0_PG_BIT and X86_CR4_PAE_BIT in kvm_valid_sregs() arm64: KVM: Fix SMCCC handling of unimplemented SMC/HVC calls KVM: arm64: Fix GICv4 init when called from vgic_its_create KVM: arm/arm64: Check pagesize when allocating a hugepage at Stage 2
2018-01-19x86/retpoline: Optimize inline assembler for vmexit_fill_RSBAndi Kleen
The generated assembler for the C fill RSB inline asm operations has several issues: - The C code sets up the loop register, which is then immediately overwritten in __FILL_RETURN_BUFFER with the same value again. - The C code also passes in the iteration count in another register, which is not used at all. Remove these two unnecessary operations. Just rely on the single constant passed to the macro for the iterations. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Cc: dave.hansen@intel.com Cc: gregkh@linuxfoundation.org Cc: torvalds@linux-foundation.org Cc: arjan@linux.intel.com Link: https://lkml.kernel.org/r/20180117225328.15414-1-andi@firstfloor.org
2018-01-19kprobes/x86: Disable optimizing on the function jumps to indirect thunkMasami Hiramatsu
Since indirect jump instructions will be replaced by jump to __x86_indirect_thunk_*, those jmp instruction must be treated as an indirect jump. Since optprobe prohibits to optimize probes in the function which uses an indirect jump, it also needs to find out the function which jump to __x86_indirect_thunk_* and disable optimization. Add a check that the jump target address is between the __indirect_thunk_start/end when optimizing kprobe. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/151629212062.10241.6991266100233002273.stgit@devbox
2018-01-19kprobes/x86: Blacklist indirect thunk functions for kprobesMasami Hiramatsu
Mark __x86_indirect_thunk_* functions as blacklist for kprobes because those functions can be called from anywhere in the kernel including blacklist functions of kprobes. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/151629209111.10241.5444852823378068683.stgit@devbox
2018-01-19retpoline: Introduce start/end markers of indirect thunkMasami Hiramatsu
Introduce start/end markers of __x86_indirect_thunk_* functions. To make it easy, consolidate .text.__x86.indirect_thunk.* sections to one .text.__x86.indirect_thunk section and put it in the end of kernel text section and adds __indirect_thunk_start/end so that other subsystem (e.g. kprobes) can identify it. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/151629206178.10241.6828804696410044771.stgit@devbox
2018-01-19x86/mce: Make machine check speculation protectedThomas Gleixner
The machine check idtentry uses an indirect branch directly from the low level code. This evades the speculation protection. Replace it by a direct call into C code and issue the indirect call there so the compiler can apply the proper speculation protection. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by:Borislav Petkov <bp@alien8.de> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Niced-by: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801181626290.1847@nanos
2018-01-18x86/mm: Rework wbinvd, hlt operation in stop_this_cpu()Tom Lendacky
Some issues have been reported with the for loop in stop_this_cpu() that issues the 'wbinvd; hlt' sequence. Reverting this sequence to halt() has been shown to resolve the issue. However, the wbinvd is needed when running with SME. The reason for the wbinvd is to prevent cache flush races between encrypted and non-encrypted entries that have the same physical address. This can occur when kexec'ing from memory encryption active to inactive or vice-versa. The important thing is to not have outside of kernel text memory references (such as stack usage), so the usage of the native_*() functions is needed since these expand as inline asm sequences. So instead of reverting the change, rework the sequence. Move the wbinvd instruction outside of the for loop as native_wbinvd() and make its execution conditional on X86_FEATURE_SME. In the for loop, change the asm 'wbinvd; hlt' sequence back to a halt sequence but use the native_halt() call. Fixes: bba4ed011a52 ("x86/mm, kexec: Allow kexec to be used with SME") Reported-by: Dave Young <dyoung@redhat.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Dave Young <dyoung@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Yu Chen <yu.c.chen@intel.com> Cc: Baoquan He <bhe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: kexec@lists.infradead.org Cc: ebiederm@redhat.com Cc: Borislav Petkov <bp@alien8.de> Cc: Rui Zhang <rui.zhang@intel.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180117234141.21184.44067.stgit@tlendack-t1.amdoffice.net
2018-01-17Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes: - A rather involved set of memory hardware encryption fixes to support the early loading of microcode files via the initrd. These are larger than what we normally take at such a late -rc stage, but there are two mitigating factors: 1) much of the changes are limited to the SME code itself 2) being able to early load microcode has increased importance in the post-Meltdown/Spectre era. - An IRQ vector allocator fix - An Intel RDT driver use-after-free fix - An APIC driver bug fix/revert to make certain older systems boot again - A pkeys ABI fix - TSC calibration fixes - A kdump fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic/vector: Fix off by one in error path x86/intel_rdt/cqm: Prevent use after free x86/mm: Encrypt the initrd earlier for BSP microcode update x86/mm: Prepare sme_encrypt_kernel() for PAGE aligned encryption x86/mm: Centralize PMD flags in sme_encrypt_kernel() x86/mm: Use a struct to reduce parameters for SME PGD mapping x86/mm: Clean up register saving in the __enc_copy() assembly code x86/idt: Mark IDT tables __initconst Revert "x86/apic: Remove init_bsp_APIC()" x86/mm/pkeys: Fix fill_sig_info_pkey x86/tsc: Print tsc_khz, when it differs from cpu_khz x86/tsc: Fix erroneous TSC rate on Skylake Xeon x86/tsc: Future-proof native_calibrate_tsc() kdump: Write the correct address of mem_section into vmcoreinfo
2018-01-17Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 perf fix from Ingo Molnar: "An Intel RAPL events fix" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/rapl: Fix Haswell and Broadwell server RAPL event
2018-01-17Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 pti bits and fixes from Thomas Gleixner: "This last update contains: - An objtool fix to prevent a segfault with the gold linker by changing the invocation order. That's not just for gold, it's a general robustness improvement. - An improved error message for objtool which spares tearing hairs. - Make KASAN fail loudly if there is not enough memory instead of oopsing at some random place later - RSB fill on context switch to prevent RSB underflow and speculation through other units. - Make the retpoline/RSB functionality work reliably for both Intel and AMD - Add retpoline to the module version magic so mismatch can be detected - A small (non-fix) update for cpufeatures which prevents cpu feature clashing for the upcoming extra mitigation bits to ease backporting" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: module: Add retpoline tag to VERMAGIC x86/cpufeature: Move processor tracing out of scattered features objtool: Improve error message for bad file argument objtool: Fix seg fault with gold linker x86/retpoline: Add LFENCE to the retpoline/RSB filling RSB macros x86/retpoline: Fill RSB on context switch for affected CPUs x86/kasan: Panic if there is not enough memory to boot
2018-01-17KVM/x86: Fix wrong macro references of X86_CR0_PG_BIT and X86_CR4_PAE_BIT in ↵Tianyu Lan
kvm_valid_sregs() kvm_valid_sregs() should use X86_CR0_PG and X86_CR4_PAE to check bit status rather than X86_CR0_PG_BIT and X86_CR4_PAE_BIT. This patch is to fix it. Fixes: f29810335965a(KVM/x86: Check input paging mode when cs.l is set) Reported-by: Jeremi Piotrowski <jeremi.piotrowski@gmail.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-01-17x86/apic/vector: Fix off by one in error pathThomas Gleixner
Keith reported the following warning: WARNING: CPU: 28 PID: 1420 at kernel/irq/matrix.c:222 irq_matrix_remove_managed+0x10f/0x120 x86_vector_free_irqs+0xa1/0x180 x86_vector_alloc_irqs+0x1e4/0x3a0 msi_domain_alloc+0x62/0x130 The reason for this is that if the vector allocation fails the error handling code tries to free the failed vector as well, which causes the above imbalance warning to trigger. Adjust the error path to handle this correctly. Fixes: b5dc8e6c21e7 ("x86/irq: Use hierarchical irqdomain to manage CPU interrupt vectors") Reported-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Keith Busch <keith.busch@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801161217300.1823@nanos
2018-01-17x86/intel_rdt/cqm: Prevent use after freeThomas Gleixner
intel_rdt_iffline_cpu() -> domain_remove_cpu() frees memory first and then proceeds accessing it. BUG: KASAN: use-after-free in find_first_bit+0x1f/0x80 Read of size 8 at addr ffff883ff7c1e780 by task cpuhp/31/195 find_first_bit+0x1f/0x80 has_busy_rmid+0x47/0x70 intel_rdt_offline_cpu+0x4b4/0x510 Freed by task 195: kfree+0x94/0x1a0 intel_rdt_offline_cpu+0x17d/0x510 Do the teardown first and then free memory. Fixes: 24247aeeabe9 ("x86/intel_rdt/cqm: Improve limbo list processing") Reported-by: Joseph Salisbury <joseph.salisbury@canonical.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Peter Zilstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: "Roderick W. Smith" <rod.smith@canonical.com> Cc: 1733662@bugs.launchpad.net Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801161957510.2366@nanos
2018-01-17x86/cpufeature: Move processor tracing out of scattered featuresPaolo Bonzini
Processor tracing is already enumerated in word 9 (CPUID[7,0].EBX), so do not duplicate it in the scattered features word. Besides being more tidy, this will be useful for KVM when it presents processor tracing to the guests. KVM selects host features that are supported by both the host kernel (depending on command line options, CPU errata, or whatever) and KVM. Whenever a full feature word exists, KVM's code is written in the expectation that the CPUID bit number matches the X86_FEATURE_* bit number, but this is not the case for X86_FEATURE_INTEL_PT. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luwei Kang <luwei.kang@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm@vger.kernel.org Link: http://lkml.kernel.org/r/1516117345-34561-1-git-send-email-pbonzini@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16x86/PCI: Enable AMD 64-bit window on resume=?UTF-8?q?Christian=20K=C3=B6nig?=
Reenable the 64-bit window during resume. Fixes: fa564ad96366 ("x86/PCI: Enable a 64bit BAR on AMD Family 15h (Models 00-1f, 30-3f, 60-7f)") Reported-by: Tom St Denis <tom.stdenis@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-01-16x86/mm: Encrypt the initrd earlier for BSP microcode updateTom Lendacky
Currently the BSP microcode update code examines the initrd very early in the boot process. If SME is active, the initrd is treated as being encrypted but it has not been encrypted (in place) yet. Update the early boot code that encrypts the kernel to also encrypt the initrd so that early BSP microcode updates work. Tested-by: Gabriel Craciunescu <nix.or.die@gmail.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.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/20180110192634.6026.10452.stgit@tlendack-t1.amdoffice.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16x86/mm: Prepare sme_encrypt_kernel() for PAGE aligned encryptionTom Lendacky
In preparation for encrypting more than just the kernel, the encryption support in sme_encrypt_kernel() needs to support 4KB page aligned encryption instead of just 2MB large page aligned encryption. Update the routines that populate the PGD to support non-2MB aligned addresses. This is done by creating PTE page tables for the start and end portion of the address range that fall outside of the 2MB alignment. This results in, at most, two extra pages to hold the PTE entries for each mapping of a range. Tested-by: Gabriel Craciunescu <nix.or.die@gmail.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.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/20180110192626.6026.75387.stgit@tlendack-t1.amdoffice.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16x86/mm: Centralize PMD flags in sme_encrypt_kernel()Tom Lendacky
In preparation for encrypting more than just the kernel during early boot processing, centralize the use of the PMD flag settings based on the type of mapping desired. When 4KB aligned encryption is added, this will allow either PTE flags or large page PMD flags to be used without requiring the caller to adjust. Tested-by: Gabriel Craciunescu <nix.or.die@gmail.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.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/20180110192615.6026.14767.stgit@tlendack-t1.amdoffice.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16x86/mm: Use a struct to reduce parameters for SME PGD mappingTom Lendacky
In preparation for follow-on patches, combine the PGD mapping parameters into a struct to reduce the number of function arguments and allow for direct updating of the next pagetable mapping area pointer. Tested-by: Gabriel Craciunescu <nix.or.die@gmail.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.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/20180110192605.6026.96206.stgit@tlendack-t1.amdoffice.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16x86/mm: Clean up register saving in the __enc_copy() assembly codeTom Lendacky
Clean up the use of PUSH and POP and when registers are saved in the __enc_copy() assembly function in order to improve the readability of the code. Move parameter register saving into general purpose registers earlier in the code and move all the pushes to the beginning of the function with corresponding pops at the end. We do this to prepare fixes. Tested-by: Gabriel Craciunescu <nix.or.die@gmail.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.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/20180110192556.6026.74187.stgit@tlendack-t1.amdoffice.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-15x86/retpoline: Add LFENCE to the retpoline/RSB filling RSB macrosTom Lendacky
The PAUSE instruction is currently used in the retpoline and RSB filling macros as a speculation trap. The use of PAUSE was originally suggested because it showed a very, very small difference in the amount of cycles/time used to execute the retpoline as compared to LFENCE. On AMD, the PAUSE instruction is not a serializing instruction, so the pause/jmp loop will use excess power as it is speculated over waiting for return to mispredict to the correct target. The RSB filling macro is applicable to AMD, and, if software is unable to verify that LFENCE is serializing on AMD (possible when running under a hypervisor), the generic retpoline support will be used and, so, is also applicable to AMD. Keep the current usage of PAUSE for Intel, but add an LFENCE instruction to the speculation trap for AMD. The same sequence has been adopted by GCC for the GCC generated retpolines. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Paul Turner <pjt@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: Kees Cook <keescook@google.com> Link: https://lkml.kernel.org/r/20180113232730.31060.36287.stgit@tlendack-t1.amdoffice.net
2018-01-15x86/retpoline: Fill RSB on context switch for affected CPUsDavid Woodhouse
On context switch from a shallow call stack to a deeper one, as the CPU does 'ret' up the deeper side it may encounter RSB entries (predictions for where the 'ret' goes to) which were populated in userspace. This is problematic if neither SMEP nor KPTI (the latter of which marks userspace pages as NX for the kernel) are active, as malicious code in userspace may then be executed speculatively. Overwrite the CPU's return prediction stack with calls which are predicted to return to an infinite loop, to "capture" speculation if this happens. This is required both for retpoline, and also in conjunction with IBRS for !SMEP && !KPTI. On Skylake+ the problem is slightly different, and an *underflow* of the RSB may cause errant branch predictions to occur. So there it's not so much overwrite, as *filling* the RSB to attempt to prevent it getting empty. This is only a partial solution for Skylake+ since there are many other conditions which may result in the RSB becoming empty. The full solution on Skylake+ is to use IBRS, which will prevent the problem even when the RSB becomes empty. With IBRS, the RSB-stuffing will not be required on context switch. [ tglx: Added missing vendor check and slighty massaged comments and changelog ] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Cc: gnomes@lxorguk.ukuu.org.uk Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: thomas.lendacky@amd.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kees Cook <keescook@google.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: https://lkml.kernel.org/r/1515779365-9032-1-git-send-email-dwmw@amazon.co.uk
2018-01-15x86/kasan: Panic if there is not enough memory to bootAndrey Ryabinin
Currently KASAN doesn't panic in case it don't have enough memory to boot. Instead, it crashes in some random place: kernel BUG at arch/x86/mm/physaddr.c:27! RIP: 0010:__phys_addr+0x268/0x276 Call Trace: kasan_populate_shadow+0x3f2/0x497 kasan_init+0x12e/0x2b2 setup_arch+0x2825/0x2a2c start_kernel+0xc8/0x15f4 x86_64_start_reservations+0x2a/0x2c x86_64_start_kernel+0x72/0x75 secondary_startup_64+0xa5/0xb0 Use memblock_virt_alloc_try_nid() for allocations without failure fallback. It will panic with an out of memory message. Reported-by: kernel test robot <xiaolong.ye@intel.com> Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Dmitry Vyukov <dvyukov@google.com> Cc: kasan-dev@googlegroups.com Cc: Alexander Potapenko <glider@google.com> Cc: lkp@01.org Link: https://lkml.kernel.org/r/20180110153602.18919-1-aryabinin@virtuozzo.com
2018-01-14Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixlet from Thomas Gleixner. Remove a warning about lack of compiler support for retpoline that most people can't do anything about, so it just annoys them needlessly. * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/retpoline: Remove compile time warning
2018-01-14x86/retpoline: Remove compile time warningThomas Gleixner
Remove the compile time warning when CONFIG_RETPOLINE=y and the compiler does not have retpoline support. Linus rationale for this is: It's wrong because it will just make people turn off RETPOLINE, and the asm updates - and return stack clearing - that are independent of the compiler are likely the most important parts because they are likely the ones easiest to target. And it's annoying because most people won't be able to do anything about it. The number of people building their own compiler? Very small. So if their distro hasn't got a compiler yet (and pretty much nobody does), the warning is just annoying crap. It is already properly reported as part of the sysfs interface. The compile-time warning only encourages bad things. Fixes: 76b043848fd2 ("x86/retpoline: Add initial retpoline support") Requested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: gnomes@lxorguk.ukuu.org.uk Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: thomas.lendacky@amd.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kees Cook <keescook@google.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Link: https://lkml.kernel.org/r/CA+55aFzWgquv4i6Mab6bASqYXg3ErV3XDFEYf=GEcCDQg5uAtw@mail.gmail.com
2018-01-14x86/idt: Mark IDT tables __initconstAndi Kleen
const variables must use __initconst, not __initdata. Fix this up for the IDT tables, which got it consistently wrong. Fixes: 16bc18d895ce ("x86/idt: Move 32-bit idt_descr to C code") Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20171222001821.2157-7-andi@firstfloor.org
2018-01-14Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 pti updates from Thomas Gleixner: "This contains: - a PTI bugfix to avoid setting reserved CR3 bits when PCID is disabled. This seems to cause issues on a virtual machine at least and is incorrect according to the AMD manual. - a PTI bugfix which disables the perf BTS facility if PTI is enabled. The BTS AUX buffer is not globally visible and causes the CPU to fault when the mapping disappears on switching CR3 to user space. A full fix which restores BTS on PTI is non trivial and will be worked on. - PTI bugfixes for EFI and trusted boot which make sure that the user space visible page table entries have the NX bit cleared - removal of dead code in the PTI pagetable setup functions - add PTI documentation - add a selftest for vsyscall to verify that the kernel actually implements what it advertises. - a sysfs interface to expose vulnerability and mitigation information so there is a coherent way for users to retrieve the status. - the initial spectre_v2 mitigations, aka retpoline: + The necessary ASM thunk and compiler support + The ASM variants of retpoline and the conversion of affected ASM code + Make LFENCE serializing on AMD so it can be used as speculation trap + The RSB fill after vmexit - initial objtool support for retpoline As I said in the status mail this is the most of the set of patches which should go into 4.15 except two straight forward patches still on hold: - the retpoline add on of LFENCE which waits for ACKs - the RSB fill after context switch Both should be ready to go early next week and with that we'll have covered the major holes of spectre_v2 and go back to normality" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits) x86,perf: Disable intel_bts when PTI security/Kconfig: Correct the Documentation reference for PTI x86/pti: Fix !PCID and sanitize defines selftests/x86: Add test_vsyscall x86/retpoline: Fill return stack buffer on vmexit x86/retpoline/irq32: Convert assembler indirect jumps x86/retpoline/checksum32: Convert assembler indirect jumps x86/retpoline/xen: Convert Xen hypercall indirect jumps x86/retpoline/hyperv: Convert assembler indirect jumps x86/retpoline/ftrace: Convert ftrace assembler indirect jumps x86/retpoline/entry: Convert entry assembler indirect jumps x86/retpoline/crypto: Convert crypto assembler indirect jumps x86/spectre: Add boot time option to select Spectre v2 mitigation x86/retpoline: Add initial retpoline support objtool: Allow alternatives to be ignored objtool: Detect jumps to retpoline thunks x86/pti: Make unpoison of pgd for trusted boot work for real x86/alternatives: Fix optimize_nops() checking sysfs/cpu: Fix typos in vulnerability documentation x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC ...
2018-01-14Revert "x86/apic: Remove init_bsp_APIC()"Ville Syrjälä
This reverts commit b371ae0d4a194b178817b0edfb6a7395c7aec37a. It causes boot hangs on old P3/P4 systems when the local APIC is enforced in UP mode. Reported-by: Meelis Roos <mroos@linux.ee> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Dou Liyang <douly.fnst@cn.fujitsu.com> Cc: yinghai@kernel.org Cc: bhe@redhat.com Link: https://lkml.kernel.org/r/20171128145350.21560-1-ville.syrjala@linux.intel.com
2018-01-14x86/mm/pkeys: Fix fill_sig_info_pkeyEric W. Biederman
SEGV_PKUERR is a signal specific si_code which happens to have the same numeric value as several others: BUS_MCEERR_AR, ILL_ILLTRP, FPE_FLTOVF, TRAP_HWBKPT, CLD_TRAPPED, POLL_ERR, SEGV_THREAD_ID, as such it is not safe to just test the si_code the signal number must also be tested to prevent a false positive in fill_sig_info_pkey. This error was by inspection, and BUS_MCEERR_AR appears to be a real candidate for confusion. So pass in si_signo and check for SIG_SEGV to verify that it is actually a SEGV_PKUERR Fixes: 019132ff3daf ("x86/mm/pkeys: Fill in pkey field in siginfo") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180112203135.4669-2-ebiederm@xmission.com
2018-01-14x86/tsc: Print tsc_khz, when it differs from cpu_khzLen Brown
If CPU and TSC frequency are the same the printout of the CPU frequency is valid for the TSC as well: tsc: Detected 2900.000 MHz processor If the TSC frequency is different there is no information in dmesg. Add a conditional printout: tsc: Detected 2904.000 MHz TSC Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: peterz@infradead.org Link: https://lkml.kernel.org/r/537b342debcd8e8aebc8d631015dcdf9f9ba8a26.1513920414.git.len.brown@intel.com
2018-01-14x86/tsc: Fix erroneous TSC rate on Skylake XeonLen Brown
The INTEL_FAM6_SKYLAKE_X hardcoded crystal_khz value of 25MHZ is problematic: - SKX workstations (with same model # as server variants) use a 24 MHz crystal. This results in a -4.0% time drift rate on SKX workstations. - SKX servers subject the crystal to an EMI reduction circuit that reduces its actual frequency by (approximately) -0.25%. This results in -1 second per 10 minute time drift as compared to network time. This issue can also trigger a timer and power problem, on configurations that use the LAPIC timer (versus the TSC deadline timer). Clock ticks scheduled with the LAPIC timer arrive a few usec before the time they are expected (according to the slow TSC). This causes Linux to poll-idle, when it should be in an idle power saving state. The idle and clock code do not graciously recover from this error, sometimes resulting in significant polling and measurable power impact. Stop using native_calibrate_tsc() for INTEL_FAM6_SKYLAKE_X. native_calibrate_tsc() will return 0, boot will run with tsc_khz = cpu_khz, and the TSC refined calibration will update tsc_khz to correct for the difference. [ tglx: Sanitized change log ] Fixes: 6baf3d61821f ("x86/tsc: Add additional Intel CPU models to the crystal quirk list") Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: peterz@infradead.org Cc: Prarit Bhargava <prarit@redhat.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/ff6dcea166e8ff8f2f6a03c17beab2cb436aa779.1513920414.git.len.brown@intel.com
2018-01-14x86/tsc: Future-proof native_calibrate_tsc()Len Brown
If the crystal frequency cannot be determined via CPUID(15).crystal_khz or the built-in table then native_calibrate_tsc() will still set the X86_FEATURE_TSC_KNOWN_FREQ flag which prevents the refined TSC calibration. As a consequence such systems use cpu_khz for the TSC frequency which is incorrect when cpu_khz != tsc_khz resulting in time drift. Return early when the crystal frequency cannot be retrieved without setting the X86_FEATURE_TSC_KNOWN_FREQ flag. This ensures that the refined TSC calibration is invoked. [ tglx: Steam-blastered changelog. Sigh ] Fixes: 4ca4df0b7eb0 ("x86/tsc: Mark TSC frequency determined by CPUID as known") Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: peterz@infradead.org Cc: Bin Gao <bin.gao@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/0fe2503aa7d7fc69137141fc705541a78101d2b9.1513920414.git.len.brown@intel.com