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2014-11-01x86, MCE, AMD: Assign interrupt handler only when bank supports itChen Yucong
There are some AMD CPU models which have thresholding banks but which cannot generate a thresholding interrupt. This is denoted by the bit MCi_MISC[IntP]. Make sure to check that bit before assigning the thresholding interrupt handler. Signed-off-by: Chen Yucong <slaoub@gmail.com> [ Boris: save an indentation level and rewrite commit message. ] Link: http://lkml.kernel.org/r/1412662128.28440.18.camel@debian Signed-off-by: Borislav Petkov <bp@suse.de>
2014-10-31x86_64, entry: Fix out of bounds read on sysenterAndy Lutomirski
Rusty noticed a Really Bad Bug (tm) in my NT fix. The entry code reads out of bounds, causing the NT fix to be unreliable. But, and this is much, much worse, if your stack is somehow just below the top of the direct map (or a hole), you read out of bounds and crash. Excerpt from the crash: [ 1.129513] RSP: 0018:ffff88001da4bf88 EFLAGS: 00010296 2b:* f7 84 24 90 00 00 00 testl $0x4000,0x90(%rsp) That read is deterministically above the top of the stack. I thought I even single-stepped through this code when I wrote it to check the offset, but I clearly screwed it up. Fixes: 8c7aa698baca ("x86_64, entry: Filter RFLAGS.NT on entry from userspace") Reported-by: Rusty Russell <rusty@ozlabs.org> Cc: stable@vger.kernel.org Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-31Merge 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: "Fixes from all around the place: - hyper-V 32-bit PAE guest kernel fix - two IRQ allocation fixes on certain x86 boards - intel-mid boot crash fix - intel-quark quirk - /proc/interrupts duplicate irq chip name fix - cma boot crash fix - syscall audit fix - boot crash fix with certain TSC configurations (seen on Qemu) - smpboot.c build warning fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, pageattr: Prevent overflow in slow_virt_to_phys() for X86_PAE ACPI, irq, x86: Return IRQ instead of GSI in mp_register_gsi() x86, intel-mid: Create IRQs for APB timers and RTC timers x86: Don't enable F00F workaround on Intel Quark processors x86/irq: Fix XT-PIC-XT-PIC in /proc/interrupts x86, cma: Reserve DMA contiguous area after initmem_init() i386/audit: stop scribbling on the stack frame x86, apic: Handle a bad TSC more gracefully x86: ACPI: Do not translate GSI number if IOAPIC is disabled x86/smpboot: Move data structure to its primary usage scope
2014-10-31Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "Various scheduler fixes all over the place: three SCHED_DL fixes, three sched/numa fixes, two generic race fixes and a comment fix" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/dl: Fix preemption checks sched: Update comments for CLONE_NEWNS sched: stop the unbound recursion in preempt_schedule_context() sched/fair: Fix division by zero sysctl_numa_balancing_scan_size sched/fair: Care divide error in update_task_scan_period() sched/numa: Fix unsafe get_task_struct() in task_numa_assign() sched/deadline: Fix races between rt_mutex_setprio() and dl_task_timer() sched/deadline: Don't replenish from a !SCHED_DEADLINE entity sched: Fix race between task_group and sched_task_group
2014-10-31Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Mostly tooling fixes, plus on the kernel side: - a revert for a newly introduced PMU driver which isn't complete yet and where we ran out of time with fixes (to be tried again in v3.19) - this makes up for a large chunk of the diffstat. - compilation warning fixes - a printk message fix - event_idx usage fixes/cleanups" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf probe: Trivial typo fix for --demangle perf tools: Fix report -F dso_from for data without branch info perf tools: Fix report -F dso_to for data without branch info perf tools: Fix report -F symbol_from for data without branch info perf tools: Fix report -F symbol_to for data without branch info perf tools: Fix report -F mispredict for data without branch info perf tools: Fix report -F in_tx for data without branch info perf tools: Fix report -F abort for data without branch info perf tools: Make CPUINFO_PROC an array to support different kernel versions perf callchain: Use global caching provided by libunwind perf/x86/intel: Revert incomplete and undocumented Broadwell client support perf/x86: Fix compile warnings for intel_uncore perf: Fix typos in sample code in the perf_event.h header perf: Fix and clean up initialization of pmu::event_idx perf: Fix bogus kernel printk perf diff: Add missing hists__init() call at tool start
2014-10-31ftrace/x86: Show trampoline call function in enabled_functionsSteven Rostedt (Red Hat)
The file /sys/kernel/debug/tracing/eneabled_functions is used to debug ftrace function hooks. Add to the output what function is being called by the trampoline if the arch supports it. Add support for this feature in x86_64. Cc: H. Peter Anvin <hpa@linux.intel.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-10-31ftrace/x86: Add dynamic allocated trampoline for ftrace_opsSteven Rostedt (Red Hat)
The current method of handling multiple function callbacks is to register a list function callback that calls all the other callbacks based on their hash tables and compare it to the function that the callback was called on. But this is very inefficient. For example, if you are tracing all functions in the kernel and then add a kprobe to a function such that the kprobe uses ftrace, the mcount trampoline will switch from calling the function trace callback to calling the list callback that will iterate over all registered ftrace_ops (in this case, the function tracer and the kprobes callback). That means for every function being traced it checks the hash of the ftrace_ops for function tracing and kprobes, even though the kprobes is only set at a single function. The kprobes ftrace_ops is checked for every function being traced! Instead of calling the list function for functions that are only being traced by a single callback, we can call a dynamically allocated trampoline that calls the callback directly. The function graph tracer already uses a direct call trampoline when it is being traced by itself but it is not dynamically allocated. It's trampoline is static in the kernel core. The infrastructure that called the function graph trampoline can also be used to call a dynamically allocated one. For now, only ftrace_ops that are not dynamically allocated can have a trampoline. That is, users such as function tracer or stack tracer. kprobes and perf allocate their ftrace_ops, and until there's a safe way to free the trampoline, it can not be used. The dynamically allocated ftrace_ops may, although, use the trampoline if the kernel is not compiled with CONFIG_PREEMPT. But that will come later. Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-10-29KVM: nVMX: Disable preemption while reading from shadow VMCSJan Kiszka
In order to access the shadow VMCS, we need to load it. At this point, vmx->loaded_vmcs->vmcs and the actually loaded one start to differ. If we now get preempted by Linux, vmx_vcpu_put and, on return, the vmx_vcpu_load will work against the wrong vmcs. That can cause copy_shadow_to_vmcs12 to corrupt the vmcs12 state. Fix the issue by disabling preemption during the copy operation. copy_vmcs12_to_shadow is safe from this issue as it is executed by vmx_vcpu_run when preemption is already disabled before vmentry. This bug is exposed by running Jailhouse within KVM on CPUs with shadow VMCS support. Jailhouse never expects an interrupt pending vmexit, but the bug can cause it if, after copy_shadow_to_vmcs12 is preempted, the active VMCS happens to have the virtual interrupt pending flag set in the CPU-based execution controls. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-29KVM: x86: Fix far-jump to non-canonical checkNadav Amit
Commit d1442d85cc30 ("KVM: x86: Handle errors when RIP is set during far jumps") introduced a bug that caused the fix to be incomplete. Due to incorrect evaluation, far jump to segment with L bit cleared (i.e., 32-bit segment) and RIP with any of the high bits set (i.e, RIP[63:32] != 0) set may not trigger #GP. As we know, this imposes a security problem. In addition, the condition for two warnings was incorrect. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> [Add #ifdef CONFIG_X86_64 to avoid complaints of undefined behavior. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-29KVM: emulator: fix execution close to the segment limitPaolo Bonzini
Emulation of code that is 14 bytes to the segment limit or closer (e.g. RIP = 0xFFFFFFF2 after reset) is broken because we try to read as many as 15 bytes from the beginning of the instruction, and __linearize fails when the passed (address, size) pair reaches out of the segment. To fix this, let __linearize return the maximum accessible size (clamped to 2^32-1) for usage in __do_insn_fetch_bytes, and avoid the limit check by passing zero for the desired size. For expand-down segments, __linearize is performing a redundant check. (u32)(addr.ea + size - 1) <= lim can only happen if addr.ea is close to 4GB; in this case, addr.ea + size - 1 will also fail the check against the upper bound of the segment (which is provided by the D/B bit). After eliminating the redundant check, it is simple to compute the *max_size for expand-down segments too. Now that the limit check is done in __do_insn_fetch_bytes, we want to inject a general protection fault there if size < op_size (like __linearize would have done), instead of just aborting. This fixes booting Tiano Core from emulated flash with EPT disabled. Cc: stable@vger.kernel.org Fixes: 719d5a9b2487e0562f178f61e323c3dc18a8b200 Reported-by: Borislav Petkov <bp@suse.de> Tested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-29KVM: emulator: fix error code for __linearizePaolo Bonzini
The error code for #GP and #SS is zero when the segment is used to access an operand or an instruction. It is only non-zero when a segment register is being loaded; for limit checks this means cases such as: * for #GP, when RIP is beyond the limit on a far call (before the first instruction is executed). We do not implement this check, but it would be in em_jmp_far/em_call_far. * for #SS, if the new stack overflows during an inter-privilege-level call to a non-conforming code segment. We do not implement stack switching at all. So use an error code of zero. Reviewed-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-29perf/x86/intel: Revert incomplete and undocumented Broadwell client supportIngo Molnar
These patches: 86a349a28b24 ("perf/x86/intel: Add Broadwell core support") c46e665f0377 ("perf/x86: Add INST_RETIRED.ALL workarounds") fdda3c4aacec ("perf/x86/intel: Use Broadwell cache event list for Haswell") introduced magic constants and unexplained changes: https://lkml.org/lkml/2014/10/28/1128 https://lkml.org/lkml/2014/10/27/325 https://lkml.org/lkml/2014/8/27/546 https://lkml.org/lkml/2014/10/28/546 Peter Zijlstra has attempted to help out, to clean up the mess: https://lkml.org/lkml/2014/10/28/543 But has not received helpful and constructive replies which makes me doubt wether it can all be finished in time until v3.18 is released. Despite various review feedback the author (Andi Kleen) has answered only few of the review questions and has generally been uncooperative, only giving replies when prompted repeatedly, and only giving minimal answers instead of constructively explaining and helping along the effort. That kind of behavior is not acceptable. There's also a boot crash on Intel E5-1630 v3 CPUs reported for another commit from Andi Kleen: e735b9db12d7 ("perf/x86/intel/uncore: Add Haswell-EP uncore support") https://lkml.org/lkml/2014/10/22/730 Which is not yet resolved. The uncore driver is independent in theory, but the crash makes me worry about how well all these patches were tested and makes me uneasy about the level of interminging that the Broadwell and Haswell code has received by the commits above. As a first step to resolve the mess revert the Broadwell client commits back to the v3.17 version, before we run out of time and problematic code hits a stable upstream kernel. ( If the Haswell-EP crash is not resolved via a simple fix then we'll have to revert the Haswell-EP uncore driver as well. ) The Broadwell client series has to be submitted in a clean fashion, with single, well documented changes per patch. If they are submitted in time and are accepted during review then they can possibly go into v3.19 but will need additional scrutiny due to the rocky history of this patch set. Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: eranian@google.com Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1409683455-29168-3-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-29x86, pageattr: Prevent overflow in slow_virt_to_phys() for X86_PAEDexuan Cui
pte_pfn() returns a PFN of long (32 bits in 32-PAE), so "long << PAGE_SHIFT" will overflow for PFNs above 4GB. Due to this issue, some Linux 32-PAE distros, running as guests on Hyper-V, with 5GB memory assigned, can't load the netvsc driver successfully and hence the synthetic network device can't work (we can use the kernel parameter mem=3000M to work around the issue). Cast pte_pfn() to phys_addr_t before shifting. Fixes: "commit d76565344512: x86, mm: Create slow_virt_to_phys()" Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: gregkh@linuxfoundation.org Cc: linux-mm@kvack.org Cc: olaf@aepfle.de Cc: apw@canonical.com Cc: jasowang@redhat.com Cc: dave.hansen@intel.com Cc: riel@redhat.com Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1414580017-27444-1-git-send-email-decui@microsoft.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-10-29ACPI, irq, x86: Return IRQ instead of GSI in mp_register_gsi()Jiang Liu
Function mp_register_gsi() returns blindly the GSI number for the ACPI SCI interrupt. That causes a regression when the GSI for ACPI SCI is shared with other devices. The regression was caused by commit 84245af7297ced9e8fe "x86, irq, ACPI: Change __acpi_register_gsi to return IRQ number instead of GSI" and exposed on a SuperMicro system, which shares one GSI between ACPI SCI and PCI device, with following failure: http://sourceforge.net/p/linux1394/mailman/linux1394-user/?viewmonth=201410 [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 20 low level) [ 2.699224] firewire_ohci 0000:06:00.0: failed to allocate interrupt 20 Return mp_map_gsi_to_irq(gsi, 0) instead of the GSI number. Reported-and-Tested-by: Daniel Robbins <drobbins@funtoo.org> Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: <stable@vger.kernel.org> # 3.17 Link: http://lkml.kernel.org/r/1414387308-27148-4-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-29x86, intel-mid: Create IRQs for APB timers and RTC timersJiang Liu
Intel MID platforms has no legacy interrupts, so no IRQ descriptors preallocated. We need to call mp_map_gsi_to_irq() to create IRQ descriptors for APB timers and RTC timers, otherwise it may cause invalid memory access as: [ 0.116839] BUG: unable to handle kernel NULL pointer dereference at 0000003a [ 0.123803] IP: [<c1071c0e>] setup_irq+0xf/0x4d Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Cohen <david.a.cohen@linux.intel.com> Cc: <stable@vger.kernel.org> # 3.17 Link: http://lkml.kernel.org/r/1414387308-27148-3-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-29x86: Don't enable F00F workaround on Intel Quark processorsDave Jones
The Intel Quark processor is a part of family 5, but does not have the F00F bug present in Pentiums of the same family. Pentiums were models 0 through 8, Quark is model 9. Signed-off-by: Dave Jones <davej@redhat.com> Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie> Link: http://lkml.kernel.org/r/20141028175753.GA12743@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86/mm: Avoid overlap the fixmap area on i386Minfei Huang
It is a problem when configuring high memory off where the vmalloc reserve area could end up overlapping the early_ioremap fixmap area on i386. The ordering of the VMALLOC_RESERVE space is: FIXADDR_TOP fixed_addresses FIXADDR_START early_ioremap fixed addresses FIXADDR_BOOT_START Persistent kmap area PKMAP_BASE VMALLOC_END Vmalloc area VMALLOC_START high_memory The available address we can use is lower than FIXADDR_BOOT_START. So we will set the kmap boundary below the FIXADDR_BOOT_START, if we configure high memory. If we configure high memory, the vmalloc reserve area should end up to PKMAP_BASE, otherwise should end up to FIXADDR_BOOT_START. Signed-off-by: Minfei Huang <mnfhuang@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/6B680A9E-6CE9-4C96-934B-CB01DCB58278@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86/irq: Fix XT-PIC-XT-PIC in /proc/interruptsMaciej W. Rozycki
Fix duplicate XT-PIC seen in /proc/interrupts on x86 systems that make use of 8259A Programmable Interrupt Controllers. Specifically convert output like this: CPU0 0: 76573 XT-PIC-XT-PIC timer 1: 11 XT-PIC-XT-PIC i8042 2: 0 XT-PIC-XT-PIC cascade 4: 8 XT-PIC-XT-PIC serial 6: 3 XT-PIC-XT-PIC floppy 7: 0 XT-PIC-XT-PIC parport0 8: 1 XT-PIC-XT-PIC rtc0 10: 448 XT-PIC-XT-PIC fddi0 12: 23 XT-PIC-XT-PIC eth0 14: 2464 XT-PIC-XT-PIC ide0 NMI: 0 Non-maskable interrupts ERR: 0 to one like this: CPU0 0: 122033 XT-PIC timer 1: 11 XT-PIC i8042 2: 0 XT-PIC cascade 4: 8 XT-PIC serial 6: 3 XT-PIC floppy 7: 0 XT-PIC parport0 8: 1 XT-PIC rtc0 10: 145 XT-PIC fddi0 12: 31 XT-PIC eth0 14: 2245 XT-PIC ide0 NMI: 0 Non-maskable interrupts ERR: 0 that is one like we used to have from ~2.2 till it was changed sometime. The rationale is there is no value in this duplicate information, it merely clutters output and looks ugly. We only have one handler for 8259A interrupts so there is no need to give it a name separate from the name already given to irq_chip. We could define meaningful names for handlers based on bits in the ELCR register on systems that have it or the value of the LTIM bit we use in ICW1 otherwise (hardcoded to 0 though with MCA support gone), to tell edge-triggered and level-triggered inputs apart. While that information does not affect 8259A interrupt handlers it could help people determine which lines are shareable and which are not. That is material for a separate change though. Any tools that parse /proc/interrupts are supposed not to be affected since it was many years we used the format this change converts back to. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/alpine.LFD.2.11.1410260147190.21390@eddie.linux-mips.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86/asm: Fix typo in arch/x86/kernel/asm_offset_64.cNicholas Mc Guire
Drop double entry for pt_regs_bx. This seems to be a typo - resulting in a double entry in the generated include/generated/asm-offsets.h, which is not necessary. Build-tested and booted on x86 64 box to make sure it was not doing any strange magic.... after all it was in the kernel in this form for almost 10 years. Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at> Cc: Jan Beulich <JBeulich@suse.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20141027172805.GA19760@opentech.at Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86_64/vdso: Clean up vgetcpu init and merge the vdso initcallsAndy Lutomirski
Now vdso/vma.c has a single initcall and no references to "vsyscall". Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/945c463e2804fedd8b08d63a040cbe85d55195aa.1411494540.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86_64/vdso: Remove jiffies from the vvar pageAndy Lutomirski
I think that the jiffies vvar was once used for the vgetcpu cache. That code is long gone, so let's just make jiffies be a normal variable. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/fcfee6f8749af14d96373a9e2656354ad0b95499.1411494540.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86/vdso: Make the PER_CPU segment 32 bitsAndy Lutomirski
IMO users ought not to be able to use 16-bit segments without using modify_ldt. Fortunately, it's impossible to break espfix64 by loading the PER_CPU segment into SS because it's PER_CPU is marked read-only and SS cannot contain an RO segment, but marking PER_CPU as 32-bit is less fragile. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/179f490d659307873eefd09206bebd417e2ab5ad.1411494540.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86/vdso: Make the PER_CPU segment start out accessedAndy Lutomirski
The first userspace attempt to read or write the PER_CPU segment will write the accessed bit to the GDT. This is visible to userspace using the LAR instruction, and it also pointlessly dirties a cache line. Set the segment's accessed bit at boot to prevent userspace access to segments from having side effects. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/ac63814ca4c637a08ec2fd0360d67ca67560a9ee.1411494540.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86/vdso: Change the PER_CPU segment to use struct desc_structAndy Lutomirski
This makes it easier to see what's going on. It produces exactly the same segment descriptor as the old code. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/d492f7b55136cbc60f016adae79160707b2e03b7.1411494540.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86_64/vdso: Move getcpu code from vsyscall_64.c to vdso/vma.cAndy Lutomirski
This is pure cut-and-paste. At this point, vsyscall_64.c contains only code needed for vsyscall emulation, but some of the comments and function names are still confused. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/a244daf7d3cbe71afc08ad09fdfe1866ca1f1978.1411494540.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86_64/vsyscall: Move all of the gate_area code to vsyscall_64.cAndy Lutomirski
This code exists for the sole purpose of making the vsyscall page look sort of like real userspace memory. Move it so that it lives with the rest of the vsyscall code. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/a7ee266773671a05f00b7175ca65a0dd812d2e4b.1411494540.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28sched/x86: Add a comment clarifying LDT context switchingAndy Lutomirski
The code is correct, but only for a rather subtle reason. This confused me for quite a while when I read switch_mm, so clarify the code to avoid confusing other people, too. TBH, I wouldn't be surprised if this code was only correct by accident. [ I wouldn't normally send a comment-only patch, but it took me a long time to first figure out wtf was going on here, and then to figure out why this wasn't exploitable by malicious code, and then to figure out why this oddity had no user-visible effect at all. Let's spare future readers the same confusion. ] Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/36275c99801a87d8dcf0502a41cf4e2ad81aae46.1412623954.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28sched/x86_64: Don't save flags on context switchAndy Lutomirski
Now that the kernel always runs with clean flags (in particular, NT is clear), there is no need to save and restore flags on every context switch. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Sebastian Lackner <sebastian@fds-team.de> Cc: Anish Bhatt <anish@chelsio.com> Cc: Chuck Ebbert <cebbert.lkml@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jan Beulich <jbeulich@suse.com> Link: http://lkml.kernel.org/r/bf6fb790787eb95b922157838f52712c25dda157.1412187233.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28perf/x86: Fix compile warnings for intel_uncorePeter Zijlstra
The uncore drivers require PCI and generate compile time warnings when !CONFIG_PCI. Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Stephane Eranian <eranian@google.com> Cc: Yan, Zheng <zheng.z.yan@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28perf: Fix bogus kernel printkPeter Zijlstra (Intel)
Andy spotted the fail in what was intended as a conditional printk level. Reported-by: Andy Lutomirski <luto@amacapital.net> Fixes: cc6cd47e7395 ("perf/x86: Tone down kernel messages when the PMU check fails in a virtual environment") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20141007124757.GH19379@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28sched: Kill task_preempt_count()Oleg Nesterov
task_preempt_count() is pointless if preemption counter is per-cpu, currently this is x86 only. It is only valid if the task is not running, and even in this case the only info it can provide is the state of PREEMPT_ACTIVE bit. Change its single caller to check p->on_rq instead, this should be the same if p->state != TASK_RUNNING, and kill this helper. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Kirill Tkhai <tkhai@yandex.ru> Cc: Alexander Graf <agraf@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Lameter <cl@linux.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/20141008183348.GC17495@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28sched: stop the unbound recursion in preempt_schedule_context()Oleg Nesterov
preempt_schedule_context() does preempt_enable_notrace() at the end and this can call the same function again; exception_exit() is heavy and it is quite possible that need-resched is true again. 1. Change this code to dec preempt_count() and check need_resched() by hand. 2. As Linus suggested, we can use the PREEMPT_ACTIVE bit and avoid the enable/disable dance around __schedule(). But in this case we need to move into sched/core.c. 3. Cosmetic, but x86 forgets to declare this function. This doesn't really matter because it is only called by asm helpers, still it make sense to add the declaration into asm/preempt.h to match preempt_schedule(). Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Graf <agraf@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Lameter <cl@linux.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Chuck Ebbert <cebbert.lkml@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20141005202322.GB27962@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86, cma: Reserve DMA contiguous area after initmem_init()Weijie Yang
Fengguang Wu reported a boot crash on the x86 platform via the 0-day Linux Kernel Performance Test: cma: dma_contiguous_reserve: reserving 31 MiB for global area BUG: Int 6: CR2 (null) [<41850786>] dump_stack+0x16/0x18 [<41d2b1db>] early_idt_handler+0x6b/0x6b [<41072227>] ? __phys_addr+0x2e/0xca [<41d4ee4d>] cma_declare_contiguous+0x3c/0x2d7 [<41d6d359>] dma_contiguous_reserve_area+0x27/0x47 [<41d6d4d1>] dma_contiguous_reserve+0x158/0x163 [<41d33e0f>] setup_arch+0x79b/0xc68 [<41d2b7cf>] start_kernel+0x9c/0x456 [<41d2b2ca>] i386_start_kernel+0x79/0x7d (See details at: https://lkml.org/lkml/2014/10/8/708) It is because dma_contiguous_reserve() is called before initmem_init() in x86, the variable high_memory is not initialized but accessed by __pa(high_memory) in dma_contiguous_reserve(). This patch moves dma_contiguous_reserve() after initmem_init() so that high_memory is initialized before accessed. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Weijie Yang <weijie.yang@samsung.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Cc: iamjoonsoo.kim@lge.com Cc: 'Linux-MM' <linux-mm@kvack.org> Cc: 'Weijie Yang' <weijie.yang.kh@gmail.com> Link: http://lkml.kernel.org/r/000101cfef69%2431e528a0%2495af79e0%24%25yang@samsung.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28Merge tag 'drm-intel-next-2014-10-03-no-ppgtt' of ↵Dave Airlie
git://anongit.freedesktop.org/drm-intel into drm-next Ok, new attempt, this time around with full ppgtt disabled again. drm-intel-next-2014-10-03: - first batch of skl stage 1 enabling - fixes from Rodrigo to the PSR, fbc and sink crc code - kerneldoc for the frontbuffer tracking code, runtime pm code and the basic interrupt enable/disable functions - smaller stuff all over drm-intel-next-2014-09-19: - bunch more i830M fixes from Ville - full ppgtt now again enabled by default - more ppgtt fixes from Michel Thierry and Chris Wilson - plane config work from Gustavo Padovan - spinlock clarifications - piles of smaller improvements all over, as usual * tag 'drm-intel-next-2014-10-03-no-ppgtt' of git://anongit.freedesktop.org/drm-intel: (114 commits) Revert "drm/i915: Enable full PPGTT on gen7" drm/i915: Update DRIVER_DATE to 20141003 drm/i915: Remove the duplicated logic between the two shrink phases drm/i915: kerneldoc for interrupt enable/disable functions drm/i915: Use dev_priv instead of dev in irq setup functions drm/i915: s/pm._irqs_disabled/pm.irqs_enabled/ drm/i915: Clear TX FIFO reset master override bits on chv drm/i915: Make sure hardware uses the correct swing margin/deemph bits on chv drm/i915: make sink_crc return -EIO on aux read/write failure drm/i915: Constify send buffer for intel_dp_aux_ch drm/i915: De-magic the PSR AUX message drm/i915: Reinstate error level message for non-simulated gpu hangs drm/i915: Kerneldoc for intel_runtime_pm.c drm/i915: Call runtime_pm_disable directly drm/i915: Move intel_display_set_init_power to intel_runtime_pm.c drm/i915: Bikeshed rpm functions name a bit. drm/i915: Extract intel_runtime_pm.c drm/i915: Remove intel_modeset_suspend_hw drm/i915: spelling fixes for frontbuffer tracking kerneldoc drm/i915: Tighting frontbuffer tracking around flips ...
2014-10-27ASoC: Intel: mrfld: Define sst_res_info for acpiSubhransu S. Prusty
To query resources in ACPI systems we need to define a data structure. This would be set as platform_info for the devices. Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-10-27ASoC: Intel: mrfld - Define ipc_info structureSubhransu S. Prusty
This will be used to abstract the differances in ipc offsets for different chips. Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-10-24i386/audit: stop scribbling on the stack frameEric Paris
git commit b4f0d3755c5e9cc86292d5fd78261903b4f23d4a was very very dumb. It was writing over %esp/pt_regs semi-randomly on i686 with the expected "system can't boot" results. As noted in: https://bugs.freedesktop.org/show_bug.cgi?id=85277 This patch stops fscking with pt_regs. Instead it sets up the registers for the call to __audit_syscall_entry in the most obvious conceivable way. It then does just a tiny tiny touch of magic. We need to get what started in PT_EDX into 0(%esp) and PT_ESI into 4(%esp). This is as easy as a pair of pushes. After the call to __audit_syscall_entry all we need to do is get that now useless junk off the stack (pair of pops) and reload %eax with the original syscall so other stuff can keep going about it's business. Reported-by: Paulo Zanoni <przanoni@gmail.com> Signed-off-by: Eric Paris <eparis@redhat.com> Link: http://lkml.kernel.org/r/1414037043-30647-1-git-send-email-eparis@redhat.com Cc: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-10-24Merge tag 'v3.18-rc1' into x86/urgentH. Peter Anvin
Reason: Need to apply audit patch on top of v3.18-rc1. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-10-24Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm fixes from Paolo Bonzini: "This is a pretty large update. I think it is roughly as big as what I usually had for the _whole_ rc period. There are a few bad bugs where the guest can OOPS or crash the host. We have also started looking at attack models for nested virtualization; bugs that usually result in the guest ring 0 crashing itself become more worrisome if you have nested virtualization, because the nested guest might bring down the non-nested guest as well. For current uses of nested virtualization these do not really have a security impact, but you never know and bugs are bugs nevertheless. A lot of these bugs are in 3.17 too, resulting in a large number of stable@ Ccs. I checked that all the patches apply there with no conflicts" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: kvm: vfio: fix unregister kvm_device_ops of vfio KVM: x86: Wrong assertion on paging_tmpl.h kvm: fix excessive pages un-pinning in kvm_iommu_map error path. KVM: x86: PREFETCH and HINT_NOP should have SrcMem flag KVM: x86: Emulator does not decode clflush well KVM: emulate: avoid accessing NULL ctxt->memopp KVM: x86: Decoding guest instructions which cross page boundary may fail kvm: x86: don't kill guest on unknown exit reason kvm: vmx: handle invvpid vm exit gracefully KVM: x86: Handle errors when RIP is set during far jumps KVM: x86: Emulator fixes for eip canonical checks on near branches KVM: x86: Fix wrong masking on relative jump/call KVM: x86: Improve thread safety in pit KVM: x86: Prevent host from panicking on shared MSR writes. KVM: x86: Check non-canonical addresses upon WRMSR
2014-10-24Merge tag 'stable/for-linus-3.18-b-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen bug fixes from David Vrabel: - Fix regression in xen_clocksource_read() which caused all Xen guests to crash early in boot. - Several fixes for super rare race conditions in the p2m. - Assorted other minor fixes. * tag 'stable/for-linus-3.18-b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/pci: Allocate memory for physdev_pci_device_add's optarr x86/xen: panic on bad Xen-provided memory map x86/xen: Fix incorrect per_cpu accessor in xen_clocksource_read() x86/xen: avoid race in p2m handling x86/xen: delay construction of mfn_list_list x86/xen: avoid writing to freed memory after race in p2m handling xen/balloon: Don't continue ballooning when BP_ECANCELED is encountered
2014-10-24KVM: x86: Wrong assertion on paging_tmpl.hNadav Amit
Even after the recent fix, the assertion on paging_tmpl.h is triggered. Apparently, the assertion wants to check that the PAE is always set on long-mode, but does it in incorrect way. Note that the assertion is not enabled unless the code is debugged by defining MMU_DEBUG. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24KVM: x86: PREFETCH and HINT_NOP should have SrcMem flagNadav Amit
The decode phase of the x86 emulator assumes that every instruction with the ModRM flag, and which can be used with RIP-relative addressing, has either SrcMem or DstMem. This is not the case for several instructions - prefetch, hint-nop and clflush. Adding SrcMem|NoAccess for prefetch and hint-nop and SrcMem for clflush. This fixes CVE-2014-8480. Fixes: 41061cdb98a0bec464278b4db8e894a3121671f5 Cc: stable@vger.kernel.org Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24KVM: x86: Emulator does not decode clflush wellNadav Amit
Currently, all group15 instructions are decoded as clflush (e.g., mfence, xsave). In addition, the clflush instruction requires no prefix (66/f2/f3) would exist. If prefix exists it may encode a different instruction (e.g., clflushopt). Creating a group for clflush, and different group for each prefix. This has been the case forever, but the next patch needs the cflush group in order to fix a bug introduced in 3.17. Fixes: 41061cdb98a0bec464278b4db8e894a3121671f5 Cc: stable@vger.kernel.org Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24KVM: emulate: avoid accessing NULL ctxt->memoppPaolo Bonzini
A failure to decode the instruction can cause a NULL pointer access. This is fixed simply by moving the "done" label as close as possible to the return. This fixes CVE-2014-8481. Reported-by: Andy Lutomirski <luto@amacapital.net> Cc: stable@vger.kernel.org Fixes: 41061cdb98a0bec464278b4db8e894a3121671f5 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24KVM: x86: Decoding guest instructions which cross page boundary may failNadav Amit
Once an instruction crosses a page boundary, the size read from the second page disregards the common case that part of the operand resides on the first page. As a result, fetch of long insturctions may fail, and thereby cause the decoding to fail as well. Cc: stable@vger.kernel.org Fixes: 5cfc7e0f5e5e1adf998df94f8e36edaf5d30d38e Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24kvm: x86: don't kill guest on unknown exit reasonMichael S. Tsirkin
KVM_EXIT_UNKNOWN is a kvm bug, we don't really know whether it was triggered by a priveledged application. Let's not kill the guest: WARN and inject #UD instead. Cc: stable@vger.kernel.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24kvm: vmx: handle invvpid vm exit gracefullyPetr Matousek
On systems with invvpid instruction support (corresponding bit in IA32_VMX_EPT_VPID_CAP MSR is set) guest invocation of invvpid causes vm exit, which is currently not handled and results in propagation of unknown exit to userspace. Fix this by installing an invvpid vm exit handler. This is CVE-2014-3646. Cc: stable@vger.kernel.org Signed-off-by: Petr Matousek <pmatouse@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24KVM: x86: Handle errors when RIP is set during far jumpsNadav Amit
Far jmp/call/ret may fault while loading a new RIP. Currently KVM does not handle this case, and may result in failed vm-entry once the assignment is done. The tricky part of doing so is that loading the new CS affects the VMCS/VMCB state, so if we fail during loading the new RIP, we are left in unconsistent state. Therefore, this patch saves on 64-bit the old CS descriptor and restores it if loading RIP failed. This fixes CVE-2014-3647. Cc: stable@vger.kernel.org Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24KVM: x86: Emulator fixes for eip canonical checks on near branchesNadav Amit
Before changing rip (during jmp, call, ret, etc.) the target should be asserted to be canonical one, as real CPUs do. During sysret, both target rsp and rip should be canonical. If any of these values is noncanonical, a #GP exception should occur. The exception to this rule are syscall and sysenter instructions in which the assigned rip is checked during the assignment to the relevant MSRs. This patch fixes the emulator to behave as real CPUs do for near branches. Far branches are handled by the next patch. This fixes CVE-2014-3647. Cc: stable@vger.kernel.org Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24KVM: x86: Fix wrong masking on relative jump/callNadav Amit
Relative jumps and calls do the masking according to the operand size, and not according to the address size as the KVM emulator does today. This patch fixes KVM behavior. Cc: stable@vger.kernel.org Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>