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2016-07-10x86/quirks: Add early quirk to reset Apple AirPort cardLukas Wunner
The EFI firmware on Macs contains a full-fledged network stack for downloading OS X images from osrecovery.apple.com. Unfortunately on Macs introduced 2011 and 2012, EFI brings up the Broadcom 4331 wireless card on every boot and leaves it enabled even after ExitBootServices has been called. The card continues to assert its IRQ line, causing spurious interrupts if the IRQ is shared. It also corrupts memory by DMAing received packets, allowing for remote code execution over the air. This only stops when a driver is loaded for the wireless card, which may be never if the driver is not installed or blacklisted. The issue seems to be constrained to the Broadcom 4331. Chris Milsted has verified that the newer Broadcom 4360 built into the MacBookPro11,3 (2013/2014) does not exhibit this behaviour. The chances that Apple will ever supply a firmware fix for the older machines appear to be zero. The solution is to reset the card on boot by writing to a reset bit in its mmio space. This must be done as an early quirk and not as a plain vanilla PCI quirk to successfully combat memory corruption by DMAed packets: Matthew Garrett found out in 2012 that the packets are written to EfiBootServicesData memory (http://mjg59.dreamwidth.org/11235.html). This type of memory is made available to the page allocator by efi_free_boot_services(). Plain vanilla PCI quirks run much later, in subsys initcall level. In-between a time window would be open for memory corruption. Random crashes occurring in this time window and attributed to DMAed packets have indeed been observed in the wild by Chris Bainbridge. When Matthew Garrett analyzed the memory corruption issue in 2012, he sought to fix it with a grub quirk which transitions the card to D3hot: http://git.savannah.gnu.org/cgit/grub.git/commit/?id=9d34bb85da56 This approach does not help users with other bootloaders and while it may prevent DMAed packets, it does not cure the spurious interrupts emanating from the card. Unfortunately the card's mmio space is inaccessible in D3hot, so to reset it, we have to undo the effect of Matthew's grub patch and transition the card back to D0. Note that the quirk takes a few shortcuts to reduce the amount of code: The size of BAR 0 and the location of the PM capability is identical on all affected machines and therefore hardcoded. Only the address of BAR 0 differs between models. Also, it is assumed that the BCMA core currently mapped is the 802.11 core. The EFI driver seems to always take care of this. Michael Büsch, Bjorn Helgaas and Matt Fleming contributed feedback towards finding the best solution to this problem. The following should be a comprehensive list of affected models: iMac13,1 2012 21.5" [Root Port 00:1c.3 = 8086:1e16] iMac13,2 2012 27" [Root Port 00:1c.3 = 8086:1e16] Macmini5,1 2011 i5 2.3 GHz [Root Port 00:1c.1 = 8086:1c12] Macmini5,2 2011 i5 2.5 GHz [Root Port 00:1c.1 = 8086:1c12] Macmini5,3 2011 i7 2.0 GHz [Root Port 00:1c.1 = 8086:1c12] Macmini6,1 2012 i5 2.5 GHz [Root Port 00:1c.1 = 8086:1e12] Macmini6,2 2012 i7 2.3 GHz [Root Port 00:1c.1 = 8086:1e12] MacBookPro8,1 2011 13" [Root Port 00:1c.1 = 8086:1c12] MacBookPro8,2 2011 15" [Root Port 00:1c.1 = 8086:1c12] MacBookPro8,3 2011 17" [Root Port 00:1c.1 = 8086:1c12] MacBookPro9,1 2012 15" [Root Port 00:1c.1 = 8086:1e12] MacBookPro9,2 2012 13" [Root Port 00:1c.1 = 8086:1e12] MacBookPro10,1 2012 15" [Root Port 00:1c.1 = 8086:1e12] MacBookPro10,2 2012 13" [Root Port 00:1c.1 = 8086:1e12] For posterity, spurious interrupts caused by the Broadcom 4331 wireless card resulted in splats like this (stacktrace omitted): irq 17: nobody cared (try booting with the "irqpoll" option) handlers: [<ffffffff81374370>] pcie_isr [<ffffffffc0704550>] sdhci_irq [sdhci] threaded [<ffffffffc07013c0>] sdhci_thread_irq [sdhci] [<ffffffffc0a0b960>] azx_interrupt [snd_hda_codec] Disabling IRQ #17 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=79301 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=111781 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=728916 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=895951#c16 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1009819 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1098621 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1149632#c5 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1279130 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1332732 Tested-by: Konstantin Simanov <k.simanov@stlk.ru> # [MacBookPro8,1] Tested-by: Lukas Wunner <lukas@wunner.de> # [MacBookPro9,1] Tested-by: Bryan Paradis <bryan.paradis@gmail.com> # [MacBookPro9,2] Tested-by: Andrew Worsley <amworsley@gmail.com> # [MacBookPro10,1] Tested-by: Chris Bainbridge <chris.bainbridge@gmail.com> # [MacBookPro10,2] Signed-off-by: Lukas Wunner <lukas@wunner.de> Acked-by: Rafał Miłecki <zajec5@gmail.com> Acked-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chris Milsted <cmilsted@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Michael Buesch <m@bues.ch> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: b43-dev@lists.infradead.org Cc: linux-pci@vger.kernel.org Cc: linux-wireless@vger.kernel.org Cc: stable@vger.kernel.org Cc: stable@vger.kernel.org # 123456789abc: x86/quirks: Apply nvidia_bugs quirk only on root bus Cc: stable@vger.kernel.org # 123456789abc: x86/quirks: Reintroduce scanning of secondary buses Link: http://lkml.kernel.org/r/48d0972ac82a53d460e5fce77a07b2560db95203.1465690253.git.lukas@wunner.de [ Did minor readability edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-10x86/quirks: Reintroduce scanning of secondary busesLukas Wunner
We used to scan secondary buses until the following commit that was applied in 2009: 8659c406ade3 ("x86: only scan the root bus in early PCI quirks") which commit constrained early quirks to the root bus only. Its motivation was to prevent application of the nvidia_bugs quirk on secondary buses. We're about to add a quirk to reset the Broadcom 4331 wireless card on 2011/2012 Macs, which is located on a secondary bus behind a PCIe root port. To facilitate that, reintroduce scanning of secondary buses. The commit message of 8659c406ade3 notes that scanning only the root bus "saves quite some unnecessary scanning work". The algorithm used prior to 8659c406ade3 was particularly time consuming because it scanned buses 0 to 31 brute force. To avoid lengthening boot time, employ a recursive strategy which only scans buses that are actually reachable from the root bus. Yinghai Lu pointed out that the secondary bus number read from a bridge's config space may be invalid, in particular a value of 0 would cause an infinite loop. The PCI core goes beyond that and recurses to a child bus only if its bus number is greater than the parent bus number (see pci_scan_bridge()). Since the root bus is numbered 0, this implies that secondary buses may not be 0. Do the same on early scanning. If this algorithm is found to significantly impact boot time or cause infinite loops on broken hardware, it would be possible to limit its recursion depth: The Broadcom 4331 quirk applies at depth 1, all others at depth 0, so the bus need not be scanned deeper than that for now. An alternative approach would be to revert to scanning only the root bus, and apply the Broadcom 4331 quirk to the root ports 8086:1c12, 8086:1e12 and 8086:1e16. Apple always positioned the card behind either of these three ports. The quirk would then check presence of the card in slot 0 below the root port and do its deed. Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.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: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linux-pci@vger.kernel.org Link: http://lkml.kernel.org/r/f0daa70dac1a9b2483abdb31887173eb6ab77bdf.1465690253.git.lukas@wunner.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-10x86/quirks: Apply nvidia_bugs quirk only on root busLukas Wunner
Since the following commit: 8659c406ade3 ("x86: only scan the root bus in early PCI quirks") ... early quirks are only applied to devices on the root bus. The motivation was to prevent application of the nvidia_bugs quirk on secondary buses. We're about to reintroduce scanning of secondary buses for a quirk to reset the Broadcom 4331 wireless card on 2011/2012 Macs. To prevent regressions, open code the requirement to apply nvidia_bugs only on the root bus. Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.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: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/4d5477c1d76b2f0387a780f2142bbcdd9fee869b.1465690253.git.lukas@wunner.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-08Merge 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: "Three fixes: - A boot crash fix with certain configs - a MAINTAINERS entry update - Documentation typo fixes" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/Documentation: Fix various typos in Documentation/x86/ files x86/amd_nb: Fix boot crash on non-AMD systems MAINTAINERS: Update the Calgary IOMMU entry
2016-07-01x86/amd_nb: Fix boot crash on non-AMD systemsBorislav Petkov
Fix boot crash that triggers if this driver is built into a kernel and run on non-AMD systems. AMD northbridges users call amd_cache_northbridges() and it returns a negative value to signal that we weren't able to cache/detect any northbridges on the system. At least, it should do so as all its callers expect it to do so. But it does return a negative value only when kmalloc() fails. Fix it to return -ENODEV if there are no NBs cached as otherwise, amd_nb users like amd64_edac, for example, which relies on it to know whether it should load or not, gets loaded on systems like Intel Xeons where it shouldn't. Reported-and-tested-by: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> 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/1466097230-5333-2-git-send-email-bp@alien8.de Link: https://lkml.kernel.org/r/5761BEB0.9000807@cybernetics.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-27pvclock: Get rid of __pvclock_read_cycles in function pvclock_read_flagsMinfei Huang
There is a generic function __pvclock_read_cycles to be used to get both flags and cycles. For function pvclock_read_flags, it's useless to get cycles value. To make this function be more effective, get this variable flags directly in function. Signed-off-by: Minfei Huang <mnghuan@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-27pvclock: Add CPU barriers to get correct version valueMinfei Huang
Protocol for the "version" fields is: hypervisor raises it (making it uneven) before it starts updating the fields and raises it again (making it even) when it is done. Thus the guest can make sure the time values it got are consistent by checking the version before and after reading them. Add CPU barries after getting version value just like what function vread_pvclock does, because all of callees in this function is inline. Fixes: 502dfeff239e8313bfbe906ca0a1a6827ac8481b Cc: stable@vger.kernel.org Signed-off-by: Minfei Huang <mnghuan@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-25Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 kprobe fix from Thomas Gleixner: "A single fix clearing the TF bit when a fault is single stepped" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kprobes/x86: Clear TF bit in fault on single-stepping
2016-06-24Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc fixes from Andrew Morton: "Two weeks worth of fixes here" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (41 commits) init/main.c: fix initcall_blacklisted on ia64, ppc64 and parisc64 autofs: don't get stuck in a loop if vfs_write() returns an error mm/page_owner: avoid null pointer dereference tools/vm/slabinfo: fix spelling mistake: "Ocurrences" -> "Occurrences" fs/nilfs2: fix potential underflow in call to crc32_le oom, suspend: fix oom_reaper vs. oom_killer_disable race ocfs2: disable BUG assertions in reading blocks mm, compaction: abort free scanner if split fails mm: prevent KASAN false positives in kmemleak mm/hugetlb: clear compound_mapcount when freeing gigantic pages mm/swap.c: flush lru pvecs on compound page arrival memcg: css_alloc should return an ERR_PTR value on error memcg: mem_cgroup_migrate() may be called with irq disabled hugetlb: fix nr_pmds accounting with shared page tables Revert "mm: disable fault around on emulated access bit architecture" Revert "mm: make faultaround produce old ptes" mailmap: add Boris Brezillon's email mailmap: add Antoine Tenart's email mm, sl[au]b: add __GFP_ATOMIC to the GFP reclaim mask mm: mempool: kasan: don't poot mempool objects in quarantine ...
2016-06-24x86: get rid of superfluous __GFP_REPEATMichal Hocko
__GFP_REPEAT has a rather weak semantic but since it has been introduced around 2.6.12 it has been ignored for low order allocations. PGALLOC_GFP uses __GFP_REPEAT but none of the allocation which uses this flag is for more than order-0. This means that this flag has never been actually useful here because it has always been used only for PAGE_ALLOC_COSTLY requests. Link: http://lkml.kernel.org/r/1464599699-30131-3-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Lutomirski <luto@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-24x86: fix up a few misc stack pointer vs thread_info confusionsLinus Torvalds
As the actual pointer value is the same for the thread stack allocation and the thread_info, code that confused the two worked fine, but will break when the thread info is moved away from the stack allocation. It also looks very confusing. For example, the kprobe code wanted to know the current top of stack. To do that, it used this: (unsigned long)current_thread_info() + THREAD_SIZE which did indeed give the correct value. But it's not only a fairly nonsensical expression, it's also rather complex, especially since we actually have this: static inline unsigned long current_top_of_stack(void) which not only gives us the value we are interested in, but happens to be how "current_thread_info()" is currently defined as: (struct thread_info *)(current_top_of_stack() - THREAD_SIZE); so using current_thread_info() to figure out the top of the stack really is a very round-about thing to do. The other cases are just simpler confusion about task_thread_info() vs task_stack_page(), which currently return the same pointer - but if you want the stack page, you really should be using the latter one. And there was one entirely unused assignment of the current stack to a thread_info pointer. All cleaned up to make more sense today, and make it easier to move the thread_info away from the stack in the future. No semantic changes. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-23x86: avoid avoid passing around 'thread_info' in stack dumping codeLinus Torvalds
None of the code actually wants a thread_info, it all wants a task_struct, and it's just converting to a thread_info pointer much too early. No semantic change. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-14kprobes/x86: Clear TF bit in fault on single-steppingMasami Hiramatsu
Fix kprobe_fault_handler() to clear the TF (trap flag) bit of the flags register in the case of a fault fixup on single-stepping. If we put a kprobe on the instruction which caused a page fault (e.g. actual mov instructions in copy_user_*), that fault happens on the single-stepping buffer. In this case, kprobes resets running instance so that the CPU can retry execution on the original ip address. However, current code forgets to reset the TF bit. Since this fault happens with TF bit set for enabling single-stepping, when it retries, it causes a debug exception and kprobes can not handle it because it already reset itself. On the most of x86-64 platform, it can be easily reproduced by using kprobe tracer. E.g. # cd /sys/kernel/debug/tracing # echo p copy_user_enhanced_fast_string+5 > kprobe_events # echo 1 > events/kprobes/enable And you'll see a kernel panic on do_debug(), since the debug trap is not handled by kprobes. To fix this problem, we just need to clear the TF bit when resetting running kprobe. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@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: 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: systemtap@sourceware.org Cc: stable@vger.kernel.org # All the way back to ancient kernels Link: http://lkml.kernel.org/r/20160611140648.25885.37482.stgit@devbox [ Updated the comments. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-10x86/ioapic: Fix incorrect pointers in ioapic_setup_resources()Rui Wang
On a 4-socket Brickland system, hot-removing one ioapic is fine. Hot-removing the 2nd one causes panic in mp_unregister_ioapic() while calling release_resource(). It is because the iomem_res pointer has already been released when removing the first ioapic. To explain the use of &res[num] here: res is assigned to ioapic_resources, and later in ioapic_insert_resources() we do: struct resource *r = ioapic_resources; for_each_ioapic(i) { insert_resource(&iomem_resource, r); r++; } Here 'r' is treated as an arry of 'struct resource', and the r++ ensures that each element of the array is inserted separately. Thus we should call release_resouce() on each element at &res[num]. Fix it by assigning the correct pointers to ioapics[i].iomem_res in ioapic_setup_resources(). Signed-off-by: Rui Wang <rui.y.wang@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: tony.luck@intel.com Cc: linux-pci@vger.kernel.org Cc: rjw@rjwysocki.net Cc: linux-acpi@vger.kernel.org Cc: bhelgaas@google.com Link: http://lkml.kernel.org/r/1465369193-4816-3-git-send-email-rui.y.wang@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-10x86/entry/traps: Don't force in_interrupt() to return true in IST handlersAndy Lutomirski
Forcing in_interrupt() to return true if we're not in a bona fide interrupt confuses the softirq code. This fixes warnings like: NOHZ: local_softirq_pending 282 ... which can happen when running things like selftests/x86. This will change perf's static percpu buffer usage in IST context. I think this is okay, and it's changing the behavior to match historical (pre-4.0) behavior. Signed-off-by: Andy Lutomirski <luto@kernel.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: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Fixes: 959274753857 ("x86, traps: Track entry into and exit from IST context") Link: http://lkml.kernel.org/r/cdc215f94d118d691d73df35275022331156fb45.1464130360.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08x86/cpu/AMD: Extend X86_FEATURE_TOPOEXT workaround to newer modelsBorislav Petkov
We need to reenable the topology extensions CPUID leafs on newer models too, if BIOS has disabled them, as we rely on them to get proper compute unit topology. Make the printk a once thing, while at it. 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: Rui Huang <ray.huang@amd.com> Cc: Sherry Hurwitz <sherry.hurwitz@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-hwmon@vger.kernel.org Link: http://lkml.kernel.org/r/1464775468-23355-1-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-25Merge 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: EFI, entry code, pkeys and MPX fixes, TASK_SIZE cleanups and a tsc frequency table fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Switch from TASK_SIZE to TASK_SIZE_MAX in the page fault code x86/fsgsbase/64: Use TASK_SIZE_MAX for FSBASE/GSBASE upper limits x86/mm/mpx: Work around MPX erratum SKD046 x86/entry/64: Fix stack return address retrieval in thunk x86/efi: Fix 7-parameter efi_call()s x86/cpufeature, x86/mm/pkeys: Fix broken compile-time disabling of pkeys x86/tsc: Add missing Cherrytrail frequency to the table
2016-05-23kexec: provide arch_kexec_protect(unprotect)_crashkres()Xunlei Pang
Implement the protection method for the crash kernel memory reservation for the 64-bit x86 kdump. Signed-off-by: Xunlei Pang <xlpang@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Dave Young <dyoung@redhat.com> Cc: Minfei Huang <mhuang@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-22Merge tag 'trace-v4.7-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull motr tracing updates from Steven Rostedt: "Three more changes. - I forgot that I had another selftest to stress test the ftrace instance creation. It was actually suppose to go into the 4.6 merge window, but I never committed it. I almost forgot about it again, but noticed it was missing from your tree. - Soumya PN sent me a clean up patch to not disable interrupts when taking the tasklist_lock for read, as it's unnecessary because that lock is never taken for write in irq context. - Newer gcc's can cause the jump in the function_graph code to the global ftrace_stub label to be a short jump instead of a long one. As that jump is dynamically converted to jump to the trace code to do function graph tracing, and that conversion expects a long jump it can corrupt the ftrace_stub itself (it's directly after that call). One way to prevent gcc from using a short jump is to declare the ftrace_stub as a weak function, which we do here to keep gcc from optimizing too much" * tag 'trace-v4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace/x86: Set ftrace_stub to weak to prevent gcc from using short jumps to it ftrace: Don't disable irqs when taking the tasklist_lock read_lock ftracetest: Add instance created, delete, read and enable event test
2016-05-20printk/nmi: generic solution for safe printk in NMIPetr Mladek
printk() takes some locks and could not be used a safe way in NMI context. The chance of a deadlock is real especially when printing stacks from all CPUs. This particular problem has been addressed on x86 by the commit a9edc8809328 ("x86/nmi: Perform a safe NMI stack trace on all CPUs"). The patchset brings two big advantages. First, it makes the NMI backtraces safe on all architectures for free. Second, it makes all NMI messages almost safe on all architectures (the temporary buffer is limited. We still should keep the number of messages in NMI context at minimum). Note that there already are several messages printed in NMI context: WARN_ON(in_nmi()), BUG_ON(in_nmi()), anything being printed out from MCE handlers. These are not easy to avoid. This patch reuses most of the code and makes it generic. It is useful for all messages and architectures that support NMI. The alternative printk_func is set when entering and is reseted when leaving NMI context. It queues IRQ work to copy the messages into the main ring buffer in a safe context. __printk_nmi_flush() copies all available messages and reset the buffer. Then we could use a simple cmpxchg operations to get synchronized with writers. There is also used a spinlock to get synchronized with other flushers. We do not longer use seq_buf because it depends on external lock. It would be hard to make all supported operations safe for a lockless use. It would be confusing and error prone to make only some operations safe. The code is put into separate printk/nmi.c as suggested by Steven Rostedt. It needs a per-CPU buffer and is compiled only on architectures that call nmi_enter(). This is achieved by the new HAVE_NMI Kconfig flag. The are MN10300 and Xtensa architectures. We need to clean up NMI handling there first. Let's do it separately. The patch is heavily based on the draft from Peter Zijlstra, see https://lkml.org/lkml/2015/6/10/327 [arnd@arndb.de: printk-nmi: use %zu format string for size_t] [akpm@linux-foundation.org: min_t->min - all types are size_t here] Signed-off-by: Petr Mladek <pmladek@suse.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Suggested-by: Steven Rostedt <rostedt@goodmis.org> Cc: Jan Kara <jack@suse.cz> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> [arm part] Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jiri Kosina <jkosina@suse.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: David Miller <davem@davemloft.net> Cc: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20exit_thread: accept a task parameter to be exitedJiri Slaby
We need to call exit_thread from copy_process in a fail path. So make it accept task_struct as a parameter. [v2] * s390: exit_thread_runtime_instr doesn't make sense to be called for non-current tasks. * arm: fix the comment in vfp_thread_copy * change 'me' to 'tsk' for task_struct * now we can change only archs that actually have exit_thread [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: "David S. Miller" <davem@davemloft.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen Liqin <liqin.linux@gmail.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Chris Zankel <chris@zankel.net> Cc: David Howells <dhowells@redhat.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Jonas Bonn <jonas@southpole.se> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Mikael Starvik <starvik@axis.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Russell King <linux@arm.linux.org.uk> Cc: Steven Miao <realmz6@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20ftrace/x86: Set ftrace_stub to weak to prevent gcc from using short jumps to itSteven Rostedt
Matt Fleming reported seeing crashes when enabling and disabling function profiling which uses function graph tracer. Later Namhyung Kim hit a similar issue and he found that the issue was due to the jmp to ftrace_stub in ftrace_graph_call was only two bytes, and when it was changed to jump to the tracing code, it overwrote the ftrace_stub that was after it. Masami Hiramatsu bisected this down to a binutils change: 8dcea93252a9ea7dff57e85220a719e2a5e8ab41 is the first bad commit commit 8dcea93252a9ea7dff57e85220a719e2a5e8ab41 Author: H.J. Lu <hjl.tools@gmail.com> Date: Fri May 15 03:17:31 2015 -0700 Add -mshared option to x86 ELF assembler This patch adds -mshared option to x86 ELF assembler. By default, assembler will optimize out non-PLT relocations against defined non-weak global branch targets with default visibility. The -mshared option tells the assembler to generate code which may go into a shared library where all non-weak global branch targets with default visibility can be preempted. The resulting code is slightly bigger. This option only affects the handling of branch instructions. Declaring ftrace_stub as a weak call prevents gas from using two byte jumps to it, which would be converted to a jump to the function graph code. Link: http://lkml.kernel.org/r/20160516230035.1dbae571@gandalf.local.home Reported-by: Matt Fleming <matt@codeblueprint.co.uk> Reported-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-05-20x86/fsgsbase/64: Use TASK_SIZE_MAX for FSBASE/GSBASE upper limitsAndy Lutomirski
The GSBASE upper limit exists to prevent user code from confusing the paranoid idtentry path. The FSBASE upper limit is just for consistency. There's no need to enforce a smaller limit for 32-bit tasks. Just use TASK_SIZE_MAX. This simplifies the logic and will save a few bytes of code. Signed-off-by: Andy Lutomirski <luto@kernel.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> Link: http://lkml.kernel.org/r/5357f2fe0f103eabf005773b70722451eab09a89.1462897104.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-20Merge branch 'linus' into x86/urgent, to refresh the treeIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-20x86/mm/mpx: Work around MPX erratum SKD046Dave Hansen
This erratum essentially causes the CPU to forget which privilege level it is operating on (kernel vs. user) for the purposes of MPX. This erratum can only be triggered when a system is not using Supervisor Mode Execution Prevention (SMEP). Our workaround for the erratum is to ensure that MPX can only be used in cases where SMEP is present in the processor and is enabled. This erratum only affects Core processors. Atom is unaffected. But, there is no architectural way to determine Atom vs. Core. So, we just apply this workaround to all processors. It's possible that it will mistakenly disable MPX on some Atom processsors or future unaffected Core processors. There are currently no processors that have MPX and not SMEP. It would take something akin to a hypervisor masking SMEP out on an Atom processor for this to present itself on current hardware. More details can be found at: http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/desktop-6th-gen-core-family-spec-update.pdf " SKD046 Branch Instructions May Initialize MPX Bound Registers Incorrectly Problem: Depending on the current Intel MPX (Memory Protection Extensions) configuration, execution of certain branch instructions (near CALL, near RET, near JMP, and Jcc instructions) without a BND prefix (F2H) initialize the MPX bound registers. Due to this erratum, such a branch instruction that is executed both with CPL = 3 and with CPL < 3 may not use the correct MPX configuration register (BNDCFGU or BNDCFGS, respectively) for determining whether to initialize the bound registers; it may thus initialize the bound registers when it should not, or fail to initialize them when it should. Implication: A branch instruction that has executed both in user mode and in supervisor mode (from the same linear address) may cause a #BR (bound range fault) when it should not have or may not cause a #BR when it should have. Workaround An operating system can avoid this erratum by setting CR4.SMEP[bit 20] to enable supervisor-mode execution prevention (SMEP). When SMEP is enabled, no code can be executed both with CPL = 3 and with CPL < 3. " Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160512220400.3B35F1BC@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-19Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "Highlights: - A new LSM, "LoadPin", from Kees Cook is added, which allows forcing of modules and firmware to be loaded from a specific device (this is from ChromeOS, where the device as a whole is verified cryptographically via dm-verity). This is disabled by default but can be configured to be enabled by default (don't do this if you don't know what you're doing). - Keys: allow authentication data to be stored in an asymmetric key. Lots of general fixes and updates. - SELinux: add restrictions for loading of kernel modules via finit_module(). Distinguish non-init user namespace capability checks. Apply execstack check on thread stacks" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (48 commits) LSM: LoadPin: provide enablement CONFIG Yama: use atomic allocations when reporting seccomp: Fix comment typo ima: add support for creating files using the mknodat syscall ima: fix ima_inode_post_setattr vfs: forbid write access when reading a file into memory fs: fix over-zealous use of "const" selinux: apply execstack check on thread stacks selinux: distinguish non-init user namespace capability checks LSM: LoadPin for kernel file loading restrictions fs: define a string representation of the kernel_read_file_id enumeration Yama: consolidate error reporting string_helpers: add kstrdup_quotable_file string_helpers: add kstrdup_quotable_cmdline string_helpers: add kstrdup_quotable selinux: check ss_initialized before revalidating an inode label selinux: delay inode label lookup as long as possible selinux: don't revalidate an inode's label when explicitly setting it selinux: Change bool variable name to index. KEYS: Add KEYCTL_DH_COMPUTE command ...
2016-05-17Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching Pull livepatching updates from Jiri Kosina: - remove of our own implementation of architecture-specific relocation code and leveraging existing code in the module loader to perform arch-dependent work, from Jessica Yu. The relevant patches have been acked by Rusty (for module.c) and Heiko (for s390). - live patching support for ppc64le, which is a joint work of Michael Ellerman and Torsten Duwe. This is coming from topic branch that is share between livepatching.git and ppc tree. - addition of livepatching documentation from Petr Mladek * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching: livepatch: make object/func-walking helpers more robust livepatch: Add some basic livepatch documentation powerpc/livepatch: Add live patching support on ppc64le powerpc/livepatch: Add livepatch stack to struct thread_info powerpc/livepatch: Add livepatch header livepatch: Allow architectures to specify an alternate ftrace location ftrace: Make ftrace_location_range() global livepatch: robustify klp_register_patch() API error checking Documentation: livepatch: outline Elf format and requirements for patch modules livepatch: reuse module loader code to write relocations module: s390: keep mod_arch_specific for livepatch modules module: preserve Elf information for livepatch modules Elf: add livepatch-specific Elf constants
2016-05-17Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (21 commits) gitignore: fix wording mfd: ab8500-debugfs: fix "between" in printk memstick: trivial fix of spelling mistake on management cpupowerutils: bench: fix "average" treewide: Fix typos in printk IB/mlx4: printk fix pinctrl: sirf/atlas7: fix printk spelling serial: mctrl_gpio: Grammar s/lines GPIOs/line GPIOs/, /sets/set/ w1: comment spelling s/minmum/minimum/ Blackfin: comment spelling s/divsor/divisor/ metag: Fix misspellings in comments. ia64: Fix misspellings in comments. hexagon: Fix misspellings in comments. tools/perf: Fix misspellings in comments. cris: Fix misspellings in comments. c6x: Fix misspellings in comments. blackfin: Fix misspelling of 'register' in comment. avr32: Fix misspelling of 'definitions' in comment. treewide: Fix typos in printk Doc: treewide : Fix typos in DocBook/filesystem.xml ...
2016-05-16Merge tag 'acpi-4.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "The new features here are ACPI 6.1 support (and some previously missing bits of ACPI 6.0 support) in ACPICA and two new drivers, a driver for the ACPI Generic Event Device (GED) feature introduced by ACPI 6.1 and the INT3406 thermal driver for display thermal management. Also the value returned by the _HRV (hardware revision) ACPI object will be exported to user space via sysfs now. In addition to that, ACPI on ARM64 will not depend on EXPERT any more. The rest is mostly fixes and cleanups and some code reorganization. Specifics: - In-kernel ACPICA code update to the upstream release 20160422 adding support for ACPI 6.1 along with some previously missing bits of ACPI 6.0 support, making a fair amount of fixes and cleanups and reducing divergences between the upstream ACPICA and the in-kernel code (Bob Moore, Lv Zheng, Al Stone, Aleksey Makarov, Will Miles) - ACPI Generic Event Device (GED) support and a fix for it (Sinan Kaya, Paul Gortmaker) - INT3406 thermal driver for display thermal management and ACPI backlight support code reorganization related to it (Aaron Lu, Arnd Bergmann) - Support for exporting the value returned by the _HRV (hardware revision) ACPI object via sysfs (Betty Dall) - Removal of the EXPERT dependency for ACPI on ARM64 (Mark Brown) - Rework of the handling of ACPI _OSI mechanism allowing the _OSI("Darwin") support to be overridden from the kernel command line among other things (Lv Zheng, Chen Yu) - Rework of the ACPI tables override mechanism to prepare it for the introduction of overlays support going forward (Lv Zheng, Rafael Wysocki) - Fixes related to the ECDT support and module-level execution of AML (Lv Zheng) - ACPI PCI interrupts management update to make it work better on ARM64 mostly (Sinan Kaya) - ACPI SRAT handling update to make the code process all entires in the table order regardless of the entry type (Lukasz Anaczkowski) - EFI power off support for full-hardware ACPI platforms that don't support ACPI S5 (Chen Yu) - Fixes and cleanups related to the ACPI core's sysfs interface (Dan Carpenter, Betty Dall) - acpi_dev_present() API rework to reduce possible confusion related to it (Lukas Wunner) - Removal of CLK_IS_ROOT from two ACPI drivers (Stephen Boyd)" * tag 'acpi-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (82 commits) ACPI / video: mark acpi_video_get_levels() inline Thermal / ACPI / video: add INT3406 thermal driver ACPI / GED: make evged.c explicitly non-modular ACPI / tables: Fix DSDT override mechanism ACPI / sysfs: fix error code in get_status() ACPICA: Update version to 20160422 ACPICA: Move all ASCII utilities to a common file ACPICA: ACPI 2.0, Hardware: Add access_width/bit_offset support for acpi_hw_write() ACPICA: ACPI 2.0, Hardware: Add access_width/bit_offset support in acpi_hw_read() ACPICA: Executer: Introduce a set of macros to handle bit width mask generation ACPICA: Hardware: Add optimized access bit width support ACPICA: Utilities: Add ACPI_IS_ALIGNED() macro ACPICA: Renamed some #defined flag constants for clarity ACPICA: ACPI 6.0, tools/iasl: Add support for new resource descriptors ACPICA: ACPI 6.0: Update _BIX support for new package element ACPICA: ACPI 6.1: Support for new PCCT subtable ACPICA: Refactor evaluate_object to reduce nesting ACPICA: Divergence: remove unwanted spaces for typedef ACPI,PCI,IRQ: remove SCI penalize function ACPI,PCI,IRQ: remove redundant code in acpi_irq_penalty_init() ..
2016-05-16Merge branch 'x86-platform-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 platform updates from Ingo Molnar: "The main change is the addition of SGI/UV4 support" * 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) x86/platform/UV: Fix incorrect nodes and pnodes for cpuless and memoryless nodes x86/platform/UV: Remove Obsolete GRU MMR address translation x86/platform/UV: Update physical address conversions for UV4 x86/platform/UV: Build GAM reference tables x86/platform/UV: Support UV4 socket address changes x86/platform/UV: Add obtaining GAM Range Table from UV BIOS x86/platform/UV: Add UV4 addressing discovery function x86/platform/UV: Fold blade info into per node hub info structs x86/platform/UV: Allocate common per node hub info structs on local node x86/platform/UV: Move blade local processor ID to the per cpu info struct x86/platform/UV: Move scir info to the per cpu info struct x86/platform/UV: Create per cpu info structs to replace per hub info structs x86/platform/UV: Update MMIOH setup function to work for both UV3 and UV4 x86/platform/UV: Clean up redunduncies after merge of UV4 MMR definitions x86/platform/UV: Add UV4 Specific MMR definitions x86/platform/UV: Prep for UV4 MMR updates x86/platform/UV: Add UV MMR Illegal Access Function x86/platform/UV: Add UV4 Specific Defines x86/platform/UV: Add UV Architecture Defines x86/platform/UV: Add Initial UV4 definitions ...
2016-05-16Merge branch 'x86-debug-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 debug cleanup from Ingo Molnar: "A printk() output simplification" * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/dumpstack: Combine some printk()s
2016-05-16Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanup from Ingo Molnar: "Inline optimizations" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Fix non-static inlines
2016-05-16Merge branch 'x86-boot-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Ingo Molnar: "The biggest changes in this cycle were: - prepare for more KASLR related changes, by restructuring, cleaning up and fixing the existing boot code. (Kees Cook, Baoquan He, Yinghai Lu) - simplifly/concentrate subarch handling code, eliminate paravirt_enabled() usage. (Luis R Rodriguez)" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits) x86/KASLR: Clarify purpose of each get_random_long() x86/KASLR: Add virtual address choosing function x86/KASLR: Return earliest overlap when avoiding regions x86/KASLR: Add 'struct slot_area' to manage random_addr slots x86/boot: Add missing file header comments x86/KASLR: Initialize mapping_info every time x86/boot: Comment what finalize_identity_maps() does x86/KASLR: Build identity mappings on demand x86/boot: Split out kernel_ident_mapping_init() x86/boot: Clean up indenting for asm/boot.h x86/KASLR: Improve comments around the mem_avoid[] logic x86/boot: Simplify pointer casting in choose_random_location() x86/KASLR: Consolidate mem_avoid[] entries x86/boot: Clean up pointer casting x86/boot: Warn on future overlapping memcpy() use x86/boot: Extract error reporting functions x86/boot: Correctly bounds-check relocations x86/KASLR: Clean up unused code from old 'run_size' and rename it to 'kernel_total_size' x86/boot: Fix "run_size" calculation x86/boot: Calculate decompression size during boot not build ...
2016-05-16Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds
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: - MSR access API fixes and enhancements (Andy Lutomirski) - early exception handling improvements (Andy Lutomirski) - user-space FS/GS prctl usage fixes and improvements (Andy Lutomirski) - Remove the cpu_has_*() APIs and replace them with equivalents (Borislav Petkov) - task switch micro-optimization (Brian Gerst) - 32-bit entry code simplification (Denys Vlasenko) - enhance PAT handling in enumated CPUs (Toshi Kani) ... and lots of other cleanups/fixlets" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits) x86/arch_prctl/64: Restore accidentally removed put_cpu() in ARCH_SET_GS x86/entry/32: Remove asmlinkage_protect() x86/entry/32: Remove GET_THREAD_INFO() from entry code x86/entry, sched/x86: Don't save/restore EFLAGS on task switch x86/asm/entry/32: Simplify pushes of zeroed pt_regs->REGs selftests/x86/ldt_gdt: Test set_thread_area() deletion of an active segment x86/tls: Synchronize segment registers in set_thread_area() x86/asm/64: Rename thread_struct's fs and gs to fsbase and gsbase x86/arch_prctl/64: Remove FSBASE/GSBASE < 4G optimization x86/segments/64: When load_gs_index fails, clear the base x86/segments/64: When loadsegment(fs, ...) fails, clear the base x86/asm: Make asm/alternative.h safe from assembly x86/asm: Stop depending on ptrace.h in alternative.h x86/entry: Rename is_{ia32,x32}_task() to in_{ia32,x32}_syscall() x86/asm: Make sure verify_cpu() has a good stack x86/extable: Add a comment about early exception handlers x86/msr: Set the return value to zero when native_rdmsr_safe() fails x86/paravirt: Make "unsafe" MSR accesses unsafe even if PARAVIRT=y x86/paravirt: Add paravirt_{read,write}_msr() x86/msr: Carry on after a non-"safe" MSR access fails ...
2016-05-16Merge branch 'ras-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RAS updates from Ingo Molnar: "Main changes in this cycle were: - AMD MCE/RAS handling updates (Yazen Ghannam, Aravind Gopalakrishnan) - Cleanups (Borislav Petkov) - logging fix (Tony Luck)" * 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/RAS: Add SMCA support to AMD Error Injector EDAC, mce_amd: Detect SMCA using X86_FEATURE_SMCA x86/mce: Update AMD mcheck init to use cpu_has() facilities x86/cpu: Add detection of AMD RAS Capabilities x86/mce/AMD: Save an indentation level in prepare_threshold_block() x86/mce/AMD: Disable LogDeferredInMcaStat for SMCA systems x86/mce/AMD: Log Deferred Errors using SMCA MCA_DE{STAT,ADDR} registers x86/mce: Detect local MCEs properly x86/mce: Look in genpool instead of mcelog for pending error records x86/mce: Detect and use SMCA-specific msr_ops x86/mce: Define vendor-specific MSR accessors x86/mce: Carve out writes to MCx_STATUS and MCx_CTL x86/mce: Grade uncorrected errors for SMCA-enabled systems x86/mce: Log MCEs after a warm rest on AMD, Fam17h and later x86/mce: Remove explicit smp_rmb() when starting CPUs sync x86/RAS: Rename AMD MCE injector config item
2016-05-16Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "Bigger kernel side changes: - Add backwards writing capability to the perf ring-buffer code, which is preparation for future advanced features like robust 'overwrite support' and snapshot mode. (Wang Nan) - Add pause and resume ioctls for the perf ringbuffer (Wang Nan) - x86 Intel cstate code cleanups and reorgnization (Thomas Gleixner) - x86 Intel uncore and CPU PMU driver updates (Kan Liang, Peter Zijlstra) - x86 AUX (Intel PT) related enhancements and updates (Alexander Shishkin) - x86 MSR PMU driver enhancements and updates (Huang Rui) - ... and lots of other changes spread out over 40+ commits. Biggest tooling side changes: - 'perf trace' features and enhancements. (Arnaldo Carvalho de Melo) - BPF tooling updates (Wang Nan) - 'perf sched' updates (Jiri Olsa) - 'perf probe' updates (Masami Hiramatsu) - ... plus 200+ other enhancements, fixes and cleanups to tools/ The merge commits, the shortlog and the changelogs contain a lot more details" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (249 commits) perf/core: Disable the event on a truncated AUX record perf/x86/intel/pt: Generate PMI in the STOP region as well perf buildid-cache: Use lsdir() for looking up buildid caches perf symbols: Use lsdir() for the search in kcore cache directory perf tools: Use SBUILD_ID_SIZE where applicable perf tools: Fix lsdir to set errno correctly perf trace: Move seccomp args beautifiers to tools/perf/trace/beauty/ perf trace: Move flock op beautifier to tools/perf/trace/beauty/ perf build: Add build-test for debug-frame on arm/arm64 perf build: Add build-test for libunwind cross-platforms support perf script: Fix export of callchains with recursion in db-export perf script: Fix callchain addresses in db-export perf script: Fix symbol insertion behavior in db-export perf symbols: Add dso__insert_symbol function perf scripting python: Use Py_FatalError instead of die() perf tools: Remove xrealloc and ALLOC_GROW perf help: Do not use ALLOC_GROW in add_cmd_list perf pmu: Make pmu_formats_string to check return value of strbuf perf header: Make topology checkers to check return value of strbuf perf tools: Make alias handler to check return value of strbuf ...
2016-05-16Merge branch 'efi-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI updates from Ingo Molnar: "The main changes in this cycle were: - Drop the unused EFI_SYSTEM_TABLES efi.flags bit and ensure the ARM/arm64 EFI System Table mapping is read-only (Ard Biesheuvel) - Add a comment to explain that one of the code paths in the x86/pat code is only executed for EFI boot (Matt Fleming) - Improve Secure Boot status checks on arm64 and handle unexpected errors (Linn Crosetto) - Remove the global EFI memory map variable 'memmap' as the same information is already available in efi::memmap (Matt Fleming) - Add EFI Memory Attribute table support for ARM/arm64 (Ard Biesheuvel) - Add EFI GOP framebuffer support for ARM/arm64 (Ard Biesheuvel) - Add EFI Bootloader Control driver for storing reboot(2) data in EFI variables for consumption by bootloaders (Jeremy Compostella) - Add Core EFI capsule support (Matt Fleming) - Add EFI capsule char driver (Kweh, Hock Leong) - Unify EFI memory map code for ARM and arm64 (Ard Biesheuvel) - Add generic EFI support for detecting when firmware corrupts CPU status register bits (like IRQ flags) when performing EFI runtime service calls (Mark Rutland) ... and other misc cleanups" * 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits) efivarfs: Make efivarfs_file_ioctl() static efi: Merge boolean flag arguments efi/capsule: Move 'capsule' to the stack in efi_capsule_supported() efibc: Fix excessive stack footprint warning efi/capsule: Make efi_capsule_pending() lockless efi: Remove unnecessary (and buggy) .memmap initialization from the Xen EFI driver efi/runtime-wrappers: Remove ARCH_EFI_IRQ_FLAGS_MASK #ifdef x86/efi: Enable runtime call flag checking arm/efi: Enable runtime call flag checking arm64/efi: Enable runtime call flag checking efi/runtime-wrappers: Detect firmware IRQ flag corruption efi/runtime-wrappers: Remove redundant #ifdefs x86/efi: Move to generic {__,}efi_call_virt() arm/efi: Move to generic {__,}efi_call_virt() arm64/efi: Move to generic {__,}efi_call_virt() efi/runtime-wrappers: Add {__,}efi_call_virt() templates efi/arm-init: Reserve rather than unmap the memory map for ARM as well efi: Add misc char driver interface to update EFI firmware x86/efi: Force EFI reboot to process pending capsules efi: Add 'capsule' update support ...
2016-05-16Merge branch 'core-signals-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core signal updates from Ingo Molnar: "These updates from Stas Sergeev and Andy Lutomirski, improve the sigaltstack interface by extending its ABI with the SS_AUTODISARM feature, which makes it possible to use swapcontext() in a sighandler that works on sigaltstack. Without this flag, the subsequent signal will corrupt the state of the switched-away sighandler. The inspiration is more robust dosemu signal handling" * 'core-signals-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: signals/sigaltstack: Change SS_AUTODISARM to (1U << 31) signals/sigaltstack: Report current flag bits in sigaltstack() selftests/sigaltstack: Fix the sigaltstack test on old kernels signals/sigaltstack: If SS_AUTODISARM, bypass on_sig_stack() selftests/sigaltstack: Add new testcase for sigaltstack(SS_ONSTACK|SS_AUTODISARM) signals/sigaltstack: Implement SS_AUTODISARM flag signals/sigaltstack: Prepare to add new SS_xxx flags signals/sigaltstack, x86/signals: Unify the x86 sigaltstack check with other architectures
2016-05-16Merge branches 'acpi-pci', 'acpi-misc' and 'acpi-tools'Rafael J. Wysocki
* acpi-pci: ACPI,PCI,IRQ: remove SCI penalize function ACPI,PCI,IRQ: remove redundant code in acpi_irq_penalty_init() ACPI,PCI,IRQ: reduce static IRQ array size to 16 ACPI,PCI,IRQ: reduce resource requirements * acpi-misc: ACPI / sysfs: fix error code in get_status() ACPI / device_sysfs: Clean up checkpatch errors ACPI / device_sysfs: Change _SUN and _STA show functions error return to EIO ACPI / device_sysfs: Add sysfs support for _HRV hardware revision arm64: defconfig: Enable ACPI ACPI / ARM64: Remove EXPERT dependency for ACPI on ARM64 ACPI / ARM64: Don't enable ACPI by default on ARM64 acer-wmi: Use acpi_dev_found() eeepc-wmi: Use acpi_dev_found() ACPI / utils: Rename acpi_dev_present() * acpi-tools: tools/power/acpi: close file only if it is open
2016-05-16Merge branches 'acpi-numa', 'acpi-tables' and 'acpi-osi'Rafael J. Wysocki
* acpi-numa: ACPI / SRAT: fix SRAT parsing order with both LAPIC and X2APIC present * acpi-tables: ACPI / tables: Fix DSDT override mechanism ACPI / tables: Convert initrd table override to table upgrade mechanism ACPI / x86: Cleanup initrd related code ACPI / tables: Move table override mechanisms to tables.c * acpi-osi: ACPI / osi: Collect _OSI handling into one single file ACPI / osi: Cleanup coding style issues before creating a separate OSI source file ACPI / osi: Cleanup OSI handling code to use bool ACPI / osi: Fix default _OSI(Darwin) support ACPI / osi: Add acpi_osi=!! to allow reverting acpi_osi=! ACPI / osi: Cleanup _OSI("Linux") related code before introducing new support ACPI / osi: Fix an issue that acpi_osi=!* cannot disable ACPICA internal strings Conflicts: drivers/acpi/internal.h
2016-05-16x86/cpufeature, x86/mm/pkeys: Fix broken compile-time disabling of pkeysDave Hansen
When I added support for the Memory Protection Keys processor feature, I had to reindent the REQUIRED/DISABLED_MASK macros, and also consult the later cpufeature words. I'm not quite sure how I bungled it, but I consulted the wrong word at the end. This only affected required or disabled cpu features in cpufeature words 14, 15 and 16. So, only Protection Keys itself was screwed over here. The result was that if you disabled pkeys in your .config, you might still see some code show up that should have been compiled out. There should be no functional problems, though. In verifying this patch I also realized that the DISABLE_PKU/OSPKE macros were defined backwards and that the cpu_has() check in setup_pku() was not doing the compile-time disabled checks. So also fix the macro for DISABLE_PKU/OSPKE and add a compile-time check for pkeys being enabled in setup_pku(). Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: <stable@vger.kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Dave Hansen <dave@sr71.net> 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> Fixes: dfb4a70f20c5 ("x86/cpufeature, x86/mm/pkeys: Add protection keys related CPUID definitions") Link: http://lkml.kernel.org/r/20160513221328.C200930B@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-13x86/arch_prctl/64: Restore accidentally removed put_cpu() in ARCH_SET_GSMateusz Guzik
This fixes an oversight in: 731e33e39a5b95 ("Remove FSBASE/GSBASE < 4G optimization") Signed-off-by: Mateusz Guzik <mguzik@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@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: 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> Link: http://lkml.kernel.org/r/1462913803-29634-1-git-send-email-mguzik@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-12x86/tsc: Add missing Cherrytrail frequency to the tableJeremy Compostella
Intel Cherrytrail is based on Airmont core so MSR_FSB_FREQ[2:0] = 4 means that the CPU reference clock runs at 80MHz. Add this missing frequency to the table. Signed-off-by: Jeremy Compostella <jeremy.compostella@intel.com> Link: http://lkml.kernel.org/r/87y47gty89.fsf@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-05-12x86/mce: Update AMD mcheck init to use cpu_has() facilitiesYazen Ghannam
Use cpu_has() facilities to find available RAS features rather than directly reading CPUID 0x80000007_EBX. Signed-off-by: Yazen Ghannam <Yazen.Ghannam@amd.com> [ Use the struct cpuinfo_x86 ptr instead. ] 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> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/1462971509-3856-6-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-12x86/cpu: Add detection of AMD RAS CapabilitiesYazen Ghannam
Add a new CPUID leaf to hold the contents of CPUID 0x80000007_EBX (RasCap). Define bits that are currently in use: Bit 0: McaOverflowRecov Bit 1: SUCCOR Bit 3: ScalableMca Signed-off-by: Yazen Ghannam <Yazen.Ghannam@amd.com> [ Shorten comment. ] 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> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/1462971509-3856-5-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-12x86/mce/AMD: Save an indentation level in prepare_threshold_block()Borislav Petkov
Do the !SMCA work first and then save us an indentation level for the SMCA code. No functionality change. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Aravind Gopalakrishnan <aravindksg.lkml@gmail.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: Tony Luck <tony.luck@intel.com> Cc: Yazen Ghannam <Yazen.Ghannam@amd.com> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/1462971509-3856-4-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-12x86/mce/AMD: Disable LogDeferredInMcaStat for SMCA systemsYazen Ghannam
Disable Deferred Error logging in MCA_{STATUS,ADDR} additionally for SMCA systems as this information will retrieved from MCA_DE{STAT,ADDR} on those systems. Signed-off-by: Yazen Ghannam <Yazen.Ghannam@amd.com> [ Simplify, drop SMCA_MCAX_EN_OFF define too. ] Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Aravind Gopalakrishnan <aravindksg.lkml@gmail.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: Tony Luck <tony.luck@intel.com> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/1462971509-3856-3-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-12x86/mce/AMD: Log Deferred Errors using SMCA MCA_DE{STAT,ADDR} registersYazen Ghannam
Scalable MCA provides new registers for all banks for logging deferred errors: MCA_DESTAT and MCA_DEADDR. Deferred errors are always logged to these registers. Update the AMD deferred error handler to use these registers, if available. Signed-off-by: Yazen Ghannam <Yazen.Ghannam@amd.com> [ Sanity-check __log_error() args, massage a bit. ] Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Aravind Gopalakrishnan <aravindksg.lkml@gmail.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: Tony Luck <tony.luck@intel.com> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/1462971509-3856-2-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-11Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-10x86/topology: Set x86_max_cores to 1 for CONFIG_SMP=nThomas Gleixner
Josef reported that the uncore driver trips over with CONFIG_SMP=n because x86_max_cores is 16 instead of 12. The reason is, that for SMP=n the extended topology detection is a NOOP and the cache leaf is used to determine the number of cores. That's wrong in two aspects: 1) The cache leaf enumerates the maximum addressable number of cores in the package, which is obviously not correct 2) UP has no business with topology bits at all. Make intel_num_cpu_cores() return 1 for CONFIG_SMP=n Reported-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: kernel-team <Kernel-team@fb.com> Cc: Kan Liang <kan.liang@intel.com> Link: http://lkml.kernel.org/r/761b4a2a-0332-7954-f030-c6639f949612@fb.com