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2014-06-07x86-64, modify_ldt: Make support for 16-bit segments a runtime optionLinus Torvalds
commit fa81511bb0bbb2b1aace3695ce869da9762624ff upstream. Checkin: b3b42ac2cbae x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels disabled 16-bit segments on 64-bit kernels due to an information leak. However, it does seem that people are genuinely using Wine to run old 16-bit Windows programs on Linux. A proper fix for this ("espfix64") is coming in the upcoming merge window, but as a temporary fix, create a sysctl to allow the administrator to re-enable support for 16-bit segments. It adds a "/proc/sys/abi/ldt16" sysctl that defaults to zero (off). If you hit this issue and care about your old Windows program more than you care about a kernel stack address information leak, you can do echo 1 > /proc/sys/abi/ldt16 as root (add it to your startup scripts), and you should be ok. The sysctl table is only added if you have COMPAT support enabled on x86-64, but I assume anybody who runs old windows binaries very much does that ;) Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/CA%2B55aFw9BPoD10U1LfHbOMpHWZkvJTkMcfCs9s3urPr1YyWBxw@mail.gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-06x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernelsH. Peter Anvin
commit b3b42ac2cbae1f3cecbb6229964a4d48af31d382 upstream. The IRET instruction, when returning to a 16-bit segment, only restores the bottom 16 bits of the user space stack pointer. We have a software workaround for that ("espfix") for the 32-bit kernel, but it relies on a nonzero stack segment base which is not available in 32-bit mode. Since 16-bit support is somewhat crippled anyway on a 64-bit kernel (no V86 mode), and most (if not quite all) 64-bit processors support virtualization for the users who really need it, simply reject attempts at creating a 16-bit segment when running on top of a 64-bit kernel. Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/n/tip-kicdm89kzw9lldryb1br9od0@git.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-06ftrace/x86: One more missing sync after fixup of function modification failurePetr Mladek
commit 12729f14d8357fb845d75155228b21e76360272d upstream. If a failure occurs while modifying ftrace function, it bails out and will remove the tracepoints to be back to what the code originally was. There is missing the final sync run across the CPUs after the fix up is done and before the ftrace int3 handler flag is reset. Here's the description of the problem: CPU0 CPU1 ---- ---- remove_breakpoint(); modifying_ftrace_code = 0; [still sees breakpoint] <takes trap> [sees modifying_ftrace_code as zero] [no breakpoint handler] [goto failed case] [trap exception - kernel breakpoint, no handler] BUG() Link: http://lkml.kernel.org/r/1393258342-29978-2-git-send-email-pmladek@suse.cz Fixes: 8a4d0a687a5 "ftrace: Use breakpoint method to update ftrace caller" Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-26x86: Adjust irq remapping quirk for older revisions of 5500/5520 chipsetsNeil Horman
commit 6f8a1b335fde143b7407036e2368d3cd6eb55674 upstream. Commit 03bbcb2e7e2 (iommu/vt-d: add quirk for broken interrupt remapping on 55XX chipsets) properly disables irq remapping on the 5500/5520 chipsets that don't correctly perform that feature. However, when I wrote it, I followed the errata sheet linked in that commit too closely, and explicitly tied the activation of the quirk to revision 0x13 of the chip, under the assumption that earlier revisions were not in the field. Recently a system was reported to be suffering from this remap bug and the quirk hadn't triggered, because the revision id register read at a lower value that 0x13, so the quirk test failed improperly. Given this, it seems only prudent to adjust this quirk so that any revision less than 0x13 has the quirk asserted. [ tglx: Removed the 0x12 comparison of pci id 3405 as this is covered by the <= 0x13 check already ] Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Link: http://lkml.kernel.org/r/1394649873-14913-1-git-send-email-nhorman@tuxdriver.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-26x86, hyperv: Bypass the timer_irq_works() checkJason Wang
commit ca3ba2a2f4a49a308e7d78c784d51b2332064f15 upstream. This patch bypass the timer_irq_works() check for hyperv guest since: - It was guaranteed to work. - timer_irq_works() may fail sometime due to the lpj calibration were inaccurate in a hyperv guest or a buggy host. In the future, we should get the tsc frequency from hypervisor and use preset lpj instead. [ hpa: I would prefer to not defer things to "the future" in the future... ] Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Acked-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Link: http://lkml.kernel.org/r/1393558229-14755-1-git-send-email-jasowang@redhat.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-19Merge tag 'pci-v3.14-fixes-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI resource management fix from Bjorn Helgaas: "This is a fix for an AGP regression exposed by e501b3d87f00 ("agp: Support 64-bit APBASE"), which we merged in v3.14-rc1. We've warned about the conflict between the GART and PCI resources and cleared out the PCI resource for a long time, but after e501b3d87f00, we still *use* that cleared-out PCI resource. I think the GART resource is incorrect, so this patch removes it" * tag 'pci-v3.14-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: Revert "[PATCH] Insert GART region into resource map"
2014-03-18Revert "[PATCH] Insert GART region into resource map"Bjorn Helgaas
This reverts commit 56dd669a138c, which makes the GART visible in /proc/iomem. This fixes a regression: e501b3d87f00 ("agp: Support 64-bit APBASE") exposed an existing problem with a conflict between the GART region and a PCI BAR region. The GART addresses are bus addresses, not CPU addresses, and therefore should not be inserted in iomem_resource. On many machines, the GART region is addressable by the CPU as well as by an AGP master, but CPU addressability is not required by the spec. On some of these machines, the GART is mapped by a PCI BAR, and in that case, the PCI core automatically inserts it into iomem_resource, just as it does for all BARs. Inserting it here means we'll have a conflict if the PCI core later tries to claim the GART region, so let's drop the insertion here. The conflict indirectly causes X failures, as reported by Jouni in the bugzilla below. We detected the conflict even before e501b3d87f00, but after it the AGP code (fix_northbridge()) uses the PCI resource (which is zeroed because of the conflict) instead of reading the BAR again. Conflicts: arch/x86_64/kernel/aperture.c Fixes: e501b3d87f00 agp: Support 64-bit APBASE Link: https://bugzilla.kernel.org/show_bug.cgi?id=72201 Reported-and-tested-by: Jouni Mettälä <jtmettala@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-03-16Merge 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: "Misc smaller fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: Fix leak in uncore_type_init failure paths perf machine: Use map as success in ip__resolve_ams perf symbols: Fix crash in elf_section_by_name perf trace: Decode architecture-specific signal numbers
2014-03-14Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Peter Anvin: "Two x86 fixes: Suresh's eager FPU fix, and a fix to the NUMA quirk for AMD northbridges. This only includes Suresh's fix patch, not the "mostly a cleanup" patch which had __init issues" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/amd/numa: Fix northbridge quirk to assign correct NUMA node x86, fpu: Check tsk_used_math() in kernel_fpu_end() for eager FPU
2014-03-14x86/amd/numa: Fix northbridge quirk to assign correct NUMA nodeDaniel J Blueman
For systems with multiple servers and routed fabric, all northbridges get assigned to the first server. Fix this by also using the node reported from the PCI bus. For single-fabric systems, the northbriges are on PCI bus 0 by definition, which are on NUMA node 0 by definition, so this is invarient on most systems. Tested on fam10h and fam15h single and multi-fabric systems and candidate for stable. Signed-off-by: Daniel J Blueman <daniel@numascale.com> Acked-by: Steffen Persvold <sp@numascale.com> Acked-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1394710981-3596-1-git-send-email-daniel@numascale.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11x86, fpu: Check tsk_used_math() in kernel_fpu_end() for eager FPUSuresh Siddha
For non-eager fpu mode, thread's fpu state is allocated during the first fpu usage (in the context of device not available exception). This (math_state_restore()) can be a blocking call and hence we enable interrupts (which were originally disabled when the exception happened), allocate memory and disable interrupts etc. But the eager-fpu mode, call's the same math_state_restore() from kernel_fpu_end(). The assumption being that tsk_used_math() is always set for the eager-fpu mode and thus avoid the code path of enabling interrupts, allocating fpu state using blocking call and disable interrupts etc. But the below issue was noticed by Maarten Baert, Nate Eldredge and few others: If a user process dumps core on an ecrypt fs while aesni-intel is loaded, we get a BUG() in __find_get_block() complaining that it was called with interrupts disabled; then all further accesses to our ecrypt fs hang and we have to reboot. The aesni-intel code (encrypting the core file that we are writing) needs the FPU and quite properly wraps its code in kernel_fpu_{begin,end}(), the latter of which calls math_state_restore(). So after kernel_fpu_end(), interrupts may be disabled, which nobody seems to expect, and they stay that way until we eventually get to __find_get_block() which barfs. For eager fpu, most the time, tsk_used_math() is true. At few instances during thread exit, signal return handling etc, tsk_used_math() might be false. In kernel_fpu_end(), for eager-fpu, call math_state_restore() only if tsk_used_math() is set. Otherwise, don't bother. Kernel code path which cleared tsk_used_math() knows what needs to be done with the fpu state. Reported-by: Maarten Baert <maarten-baert@hotmail.com> Reported-by: Nate Eldredge <nate@thatsmathematics.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Suresh Siddha <sbsiddha@gmail.com> Link: http://lkml.kernel.org/r/1391410583.3801.6.camel@europa Cc: George Spelvin <linux@horizon.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-11x86: Remove CONFIG_X86_OOSTOREDave Jones
This was an optimization that made memcpy type benchmarks a little faster on ancient (Circa 1998) IDT Winchip CPUs. In real-life workloads, it wasn't even noticable, and I doubt anyone is running benchmarks on 16 year old silicon any more. Given this code has likely seen very little use over the last decade, let's just remove it. Signed-off-by: Dave Jones <davej@fedoraproject.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-11perf/x86: Fix leak in uncore_type_init failure pathsDave Jones
The error path of uncore_type_init() frees up any allocations that were made along the way, but it relies upon type->pmus being set, which only happens if the function succeeds. As type->pmus remains null in this case, the call to uncore_type_exit will do nothing. Moving the assignment earlier will allow us to actually free those allocations should something go awry. Signed-off-by: Dave Jones <davej@fedoraproject.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140306172028.GA552@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-07x86: fix compile error due to X86_TRAP_NMI use in asm filesLinus Torvalds
It's an enum, not a #define, you can't use it in asm files. Introduced in commit 5fa10196bdb5 ("x86: Ignore NMIs that come in during early boot"), and sadly I didn't compile-test things like I should have before pushing out. My weak excuse is that the x86 tree generally doesn't introduce stupid things like this (and the ARM pull afterwards doesn't cause me to do a compile-test either, since I don't cross-compile). Cc: Don Zickus <dzickus@redhat.com> Cc: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-07x86: Ignore NMIs that come in during early bootH. Peter Anvin
Don Zickus reports: A customer generated an external NMI using their iLO to test kdump worked. Unfortunately, the machine hung. Disabling the nmi_watchdog made things work. I speculated the external NMI fired, caused the machine to panic (as expected) and the perf NMI from the watchdog came in and was latched. My guess was this somehow caused the hang. ---- It appears that the latched NMI stays latched until the early page table generation on 64 bits, which causes exceptions to happen which end in IRET, which re-enable NMI. Therefore, ignore NMIs that come in during early execution, until we have proper exception handling. Reported-and-tested-by: Don Zickus <dzickus@redhat.com> Link: http://lkml.kernel.org/r/1394221143-29713-1-git-send-email-dzickus@redhat.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org> # v3.5+, older with some backport effort
2014-03-04Merge tag 'efi-urgent' into x86/urgentH. Peter Anvin
* Disable the new EFI 1:1 virtual mapping for SGI UV because using it causes a crash during boot - Borislav Petkov Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-04x86/efi: Quirk out SGI UVBorislav Petkov
Alex reported hitting the following BUG after the EFI 1:1 virtual mapping work was merged, kernel BUG at arch/x86/mm/init_64.c:351! invalid opcode: 0000 [#1] SMP Call Trace: [<ffffffff818aa71d>] init_extra_mapping_uc+0x13/0x15 [<ffffffff818a5e20>] uv_system_init+0x22b/0x124b [<ffffffff8108b886>] ? clockevents_register_device+0x138/0x13d [<ffffffff81028dbb>] ? setup_APIC_timer+0xc5/0xc7 [<ffffffff8108b620>] ? clockevent_delta2ns+0xb/0xd [<ffffffff818a3a92>] ? setup_boot_APIC_clock+0x4a8/0x4b7 [<ffffffff8153d955>] ? printk+0x72/0x74 [<ffffffff818a1757>] native_smp_prepare_cpus+0x389/0x3d6 [<ffffffff818957bc>] kernel_init_freeable+0xb7/0x1fb [<ffffffff81535530>] ? rest_init+0x74/0x74 [<ffffffff81535539>] kernel_init+0x9/0xff [<ffffffff81541dfc>] ret_from_fork+0x7c/0xb0 [<ffffffff81535530>] ? rest_init+0x74/0x74 Getting this thing to work with the new mapping scheme would need more work, so automatically switch to the old memmap layout for SGI UV. Acked-by: Russ Anderson <rja@sgi.com> Cc: Alex Thorlton <athorlton@sgi.com Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-02Merge 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: "Misc fixes, most of them on the tooling side" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf tools: Fix strict alias issue for find_first_bit perf tools: fix BFD detection on opensuse perf: Fix hotplug splat perf/x86: Fix event scheduling perf symbols: Destroy unused symsrcs perf annotate: Check availability of annotate when processing samples
2014-02-27perf/x86: Fix event schedulingPeter Zijlstra
Vince "Super Tester" Weaver reported a new round of syscall fuzzing (Trinity) failures, with perf WARN_ON()s triggering. He also provided traces of the failures. This is I think the relevant bit: > pec_1076_warn-2804 [000] d... 147.926153: x86_pmu_disable: x86_pmu_disable > pec_1076_warn-2804 [000] d... 147.926153: x86_pmu_state: Events: { > pec_1076_warn-2804 [000] d... 147.926156: x86_pmu_state: 0: state: .R config: ffffffffffffffff ( (null)) > pec_1076_warn-2804 [000] d... 147.926158: x86_pmu_state: 33: state: AR config: 0 (ffff88011ac99800) > pec_1076_warn-2804 [000] d... 147.926159: x86_pmu_state: } > pec_1076_warn-2804 [000] d... 147.926160: x86_pmu_state: n_events: 1, n_added: 0, n_txn: 1 > pec_1076_warn-2804 [000] d... 147.926161: x86_pmu_state: Assignment: { > pec_1076_warn-2804 [000] d... 147.926162: x86_pmu_state: 0->33 tag: 1 config: 0 (ffff88011ac99800) > pec_1076_warn-2804 [000] d... 147.926163: x86_pmu_state: } > pec_1076_warn-2804 [000] d... 147.926166: collect_events: Adding event: 1 (ffff880119ec8800) So we add the insn:p event (fd[23]). At this point we should have: n_events = 2, n_added = 1, n_txn = 1 > pec_1076_warn-2804 [000] d... 147.926170: collect_events: Adding event: 0 (ffff8800c9e01800) > pec_1076_warn-2804 [000] d... 147.926172: collect_events: Adding event: 4 (ffff8800cbab2c00) We try and add the {BP,cycles,br_insn} group (fd[3], fd[4], fd[15]). These events are 0:cycles and 4:br_insn, the BP event isn't x86_pmu so that's not visible. group_sched_in() pmu->start_txn() /* nop - BP pmu */ event_sched_in() event->pmu->add() So here we should end up with: 0: n_events = 3, n_added = 2, n_txn = 2 4: n_events = 4, n_added = 3, n_txn = 3 But seeing the below state on x86_pmu_enable(), the must have failed, because the 0 and 4 events aren't there anymore. Looking at group_sched_in(), since the BP is the leader, its event_sched_in() must have succeeded, for otherwise we would not have seen the sibling adds. But since neither 0 or 4 are in the below state; their event_sched_in() must have failed; but I don't see why, the complete state: 0,0,1:p,4 fits perfectly fine on a core2. However, since we try and schedule 4 it means the 0 event must have succeeded! Therefore the 4 event must have failed, its failure will have put group_sched_in() into the fail path, which will call: event_sched_out() event->pmu->del() on 0 and the BP event. Now x86_pmu_del() will reduce n_events; but it will not reduce n_added; giving what we see below: n_event = 2, n_added = 2, n_txn = 2 > pec_1076_warn-2804 [000] d... 147.926177: x86_pmu_enable: x86_pmu_enable > pec_1076_warn-2804 [000] d... 147.926177: x86_pmu_state: Events: { > pec_1076_warn-2804 [000] d... 147.926179: x86_pmu_state: 0: state: .R config: ffffffffffffffff ( (null)) > pec_1076_warn-2804 [000] d... 147.926181: x86_pmu_state: 33: state: AR config: 0 (ffff88011ac99800) > pec_1076_warn-2804 [000] d... 147.926182: x86_pmu_state: } > pec_1076_warn-2804 [000] d... 147.926184: x86_pmu_state: n_events: 2, n_added: 2, n_txn: 2 > pec_1076_warn-2804 [000] d... 147.926184: x86_pmu_state: Assignment: { > pec_1076_warn-2804 [000] d... 147.926186: x86_pmu_state: 0->33 tag: 1 config: 0 (ffff88011ac99800) > pec_1076_warn-2804 [000] d... 147.926188: x86_pmu_state: 1->0 tag: 1 config: 1 (ffff880119ec8800) > pec_1076_warn-2804 [000] d... 147.926188: x86_pmu_state: } > pec_1076_warn-2804 [000] d... 147.926190: x86_pmu_enable: S0: hwc->idx: 33, hwc->last_cpu: 0, hwc->last_tag: 1 hwc->state: 0 So the problem is that x86_pmu_del(), when called from a group_sched_in() that fails (for whatever reason), and without x86_pmu TXN support (because the leader is !x86_pmu), will corrupt the n_added state. Reported-and-Tested-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Stephane Eranian <eranian@google.com> Cc: Dave Jones <davej@redhat.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20140221150312.GF3104@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-25x86, kaslr: export offset in VMCOREINFO ELF notesEugene Surovegin
Include kASLR offset in VMCOREINFO ELF notes to assist in debugging. [ hpa: pushing this for v3.14 to avoid having a kernel version with kASLR where we can't debug output. ] Signed-off-by: Eugene Surovegin <surovegin@google.com> Link: http://lkml.kernel.org/r/20140123173120.GA25474@www.outflux.net Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-23Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: - a bugfix which prevents a divide by 0 panic when the newly introduced try_msr_calibrate_tsc() fails - enablement of the Baytrail platform to utilize the newfangled msr based calibration * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: tsc: Add missing Baytrail frequency to the table x86, tsc: Fallback to normal calibration if fast MSR calibration fails
2014-02-22Merge 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: "Misc fixlets from all around the place" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/uncore: Fix IVT/SNB-EP uncore CBOX NID filter table perf/x86: Correctly use FEATURE_PDCM perf, nmi: Fix unknown NMI warning perf trace: Fix ioctl 'request' beautifier build problems on !(i386 || x86_64) arches perf trace: Add fallback definition of EFD_SEMAPHORE perf list: Fix checking for supported events on older kernels perf tools: Handle PERF_RECORD_HEADER_EVENT_TYPE properly perf probe: Do not add offset twice to uprobe address perf/x86: Fix Userspace RDPMC switch perf/x86/intel/p6: Add userspace RDPMC quirk for PPro
2014-02-21perf/x86/uncore: Fix IVT/SNB-EP uncore CBOX NID filter tableStephane Eranian
This patch updates the CBOX PMU filters mapping tables for SNB-EP and IVT (model 45 and 62 respectively). The NID umask always comes in addition to another umask. When set, the NID filter is applied. The current mapping tables were missing some code/umask combinations to account for the NID umask. This patch fixes that. Cc: mingo@elte.hu Cc: ak@linux.intel.com Reviewed-by: Yan, Zheng <zheng.z.yan@intel.com> Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140219131018.GA24475@quad Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-02-21perf/x86: Correctly use FEATURE_PDCMPeter Zijlstra
The current code simply assumes Intel Arch PerfMon v2+ to have the IA32_PERF_CAPABILITIES MSR; the SDM specifies that we should check CPUID[1].ECX[15] (aka, FEATURE_PDCM) instead. This was found by KVM which implements v2+ but didn't provide the capabilities MSR. Change the code to DTRT; KVM will also implement the MSR and return 0. Cc: pbonzini@redhat.com Reported-by: "Michael S. Tsirkin" <mst@redhat.com> Suggested-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140203132903.GI8874@twins.programming.kicks-ass.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-02-21perf, nmi: Fix unknown NMI warningMarkus Metzger
When using BTS on Core i7-4*, I get the below kernel warning. $ perf record -c 1 -e branches:u ls Message from syslogd@labpc1501 at Nov 11 15:49:25 ... kernel:[ 438.317893] Uhhuh. NMI received for unknown reason 31 on CPU 2. Message from syslogd@labpc1501 at Nov 11 15:49:25 ... kernel:[ 438.317920] Do you have a strange power saving mode enabled? Message from syslogd@labpc1501 at Nov 11 15:49:25 ... kernel:[ 438.317945] Dazed and confused, but trying to continue Make intel_pmu_handle_irq() take the full exit path when returning early. Cc: eranian@google.com Cc: peterz@infradead.org Cc: mingo@kernel.org Signed-off-by: Markus Metzger <markus.t.metzger@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1392425048-5309-1-git-send-email-andi@firstfloor.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-02-20Merge branch 'fixes-for-v3.14' of ↵Linus Torvalds
git://git.linaro.org/people/mszyprowski/linux-dma-mapping Pull DMA-mapping fixes from Marek Szyprowski: "This contains fixes for incorrect atomic test in dma-mapping subsystem for ARM and x86 architecture" * 'fixes-for-v3.14' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping: x86: dma-mapping: fix GFP_ATOMIC macro usage ARM: dma-mapping: fix GFP_ATOMIC macro usage
2014-02-19x86: tsc: Add missing Baytrail frequency to the tableMika Westerberg
Intel Baytrail is based on Silvermont core so MSR_FSB_FREQ[2:0] == 0 means that the CPU reference clock runs at 83.3MHz. Add this missing frequency to the table. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Bin Gao <bin.gao@linux.intel.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1392810750-18660-2-git-send-email-mika.westerberg@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-02-19x86, tsc: Fallback to normal calibration if fast MSR calibration failsThomas Gleixner
If we cannot calibrate TSC via MSR based calibration try_msr_calibrate_tsc() stores zero to fast_calibrate and returns that to the caller. This value gets then propagated further to clockevents code resulting division by zero oops like the one below: divide error: 0000 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 3.13.0+ #47 task: ffff880075508000 ti: ffff880075506000 task.ti: ffff880075506000 RIP: 0010:[<ffffffff810aec14>] [<ffffffff810aec14>] clockevents_config.part.3+0x24/0xa0 RSP: 0000:ffff880075507e58 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffff880079c0cd80 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffffffffff RBP: ffff880075507e70 R08: 0000000000000001 R09: 00000000000000be R10: 00000000000000bd R11: 0000000000000003 R12: 000000000000b008 R13: 0000000000000008 R14: 000000000000b010 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff880079c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: ffff880079fff000 CR3: 0000000001c0b000 CR4: 00000000001006f0 Stack: ffff880079c0cd80 000000000000b008 0000000000000008 ffff880075507e88 ffffffff810aecb0 ffff880079c0cd80 ffff880075507e98 ffffffff81030168 ffff880075507ed8 ffffffff81d1104f 00000000000000c3 0000000000000000 Call Trace: [<ffffffff810aecb0>] clockevents_config_and_register+0x20/0x30 [<ffffffff81030168>] setup_APIC_timer+0xc8/0xd0 [<ffffffff81d1104f>] setup_boot_APIC_clock+0x4cc/0x4d8 [<ffffffff81d0f5de>] native_smp_prepare_cpus+0x3dd/0x3f0 [<ffffffff81d02ee9>] kernel_init_freeable+0xc3/0x205 [<ffffffff8177c910>] ? rest_init+0x90/0x90 [<ffffffff8177c91e>] kernel_init+0xe/0x120 [<ffffffff8178deec>] ret_from_fork+0x7c/0xb0 [<ffffffff8177c910>] ? rest_init+0x90/0x90 Prevent this from happening by: 1) Modifying try_msr_calibrate_tsc() to return calibration value or zero if it fails. 2) Check this return value in native_calibrate_tsc() and in case of zero fallback to use normal non-MSR based calibration. [mw: Added subject and changelog] Reported-and-tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Bin Gao <bin.gao@linux.intel.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1392810750-18660-1-git-send-email-mika.westerberg@linux.intel.com Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-02-15Merge tag 'trace-fixes-v3.14-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull twi tracing fixes from Steven Rostedt: "Two urgent fixes in the tracing utility. The first is a fix for the way the ring buffer stores timestamps. After a restructure of the code was done, the ring buffer timestamp logic missed the fact that the first event on a sub buffer is to have a zero delta, as the full timestamp is stored on the sub buffer itself. But because the delta was not cleared to zero, the timestamp for that event will be calculated as the real timestamp + the delta from the last timestamp. This can skew the timestamps of the events and have them say they happened when they didn't really happen. That's bad. The second fix is for modifying the function graph caller site. When the stop machine was removed from updating the function tracing code, it missed updating the function graph call site location. It is still modified as if it is being done via stop machine. But it's not. This can lead to a GPF and kernel crash if the function graph call site happens to lie between cache lines and one CPU is executing it while another CPU is doing the update. It would be a very hard condition to hit, but the result is severe enough to have it fixed ASAP" * tag 'trace-fixes-v3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace/x86: Use breakpoints for converting function graph caller ring-buffer: Fix first commit on sub-buffer having non-zero delta
2014-02-13x86, smap: Don't enable SMAP if CONFIG_X86_SMAP is disabledH. Peter Anvin
If SMAP support is not compiled into the kernel, don't enable SMAP in CR4 -- in fact, we should clear it, because the kernel doesn't contain the proper STAC/CLAC instructions for SMAP support. Found by Fengguang Wu's test system. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Link: http://lkml.kernel.org/r/20140213124550.GA30497@localhost Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org> # v3.7+
2014-02-11ftrace/x86: Use breakpoints for converting function graph callerSteven Rostedt (Red Hat)
When the conversion was made to remove stop machine and use the breakpoint logic instead, the modification of the function graph caller is still done directly as though it was being done under stop machine. As it is not converted via stop machine anymore, there is a possibility that the code could be layed across cache lines and if another CPU is accessing that function graph call when it is being updated, it could cause a General Protection Fault. Convert the update of the function graph caller to use the breakpoint method as well. Cc: H. Peter Anvin <hpa@zytor.com> Cc: stable@vger.kernel.org # 3.5+ Fixes: 08d636b6d4fb "ftrace/x86: Have arch x86_64 use breakpoints instead of stop machine" Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-02-11x86: dma-mapping: fix GFP_ATOMIC macro usageMarek Szyprowski
GFP_ATOMIC is not a single gfp flag, but a macro which expands to the other flags, where meaningful is the LACK of __GFP_WAIT flag. To check if caller wants to perform an atomic allocation, the code must test for a lack of the __GFP_WAIT flag. This patch fixes the issue introduced in v3.5-rc1. CC: stable@vger.kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2014-02-09x86: Use preempt_disable_notrace() in cycles_2_ns()Steven Rostedt
When debug preempt is enabled, preempt_disable() can be traced by function and function graph tracing. There's a place in the function graph tracer that calls trace_clock() which eventually calls cycles_2_ns() outside of the recursion protection. When cycles_2_ns() calls preempt_disable() it gets traced and the graph tracer will go into a recursive loop causing a crash or worse, a triple fault. Simple fix is to use preempt_disable_notrace() in cycles_2_ns, which makes sense because the preempt_disable() tracing may use that code too, and it tracing it, even with recursion protection is rather pointless. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20140204141315.2a968a72@gandalf.local.home Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-09perf/x86: Fix Userspace RDPMC switchPeter Zijlstra
The current code forgets to change the CR4 state on the current CPU. Use on_each_cpu() instead of smp_call_function(). Reported-by: Mark Davies <junk@eslaf.co.uk> Suggested-by: Mark Davies <junk@eslaf.co.uk> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: fweisbec@gmail.com Link: http://lkml.kernel.org/n/tip-69efsat90ibhnd577zy3z9gh@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-09perf/x86/intel/p6: Add userspace RDPMC quirk for PProPeter Zijlstra
PPro machines can die hard when PCE gets enabled due to a CPU erratum. The safe way it so disable it by default and keep it disabled. See erratum 26 in: http://download.intel.com/design/archives/processors/pro/docs/24268935.pdf Reported-and-Tested-by: Mark Davies <junk@eslaf.co.uk> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Stephane Eranian <eranian@google.com> Cc: Vince Weaver <vince@deater.net> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140206170815.GW2936@laptop.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-07Merge tag 'efi-urgent' into x86/urgentH. Peter Anvin
* Avoid WARN_ON() when mapping BGRT on Baytrail (EFI 32-bit). Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-06x86, microcode, AMD: Unify valid container checksBorislav Petkov
For additional coverage, BorisO and friends unknowlingly did swap AMD microcode with Intel microcode blobs in order to see what happens. What did happen on 32-bit was [ 5.722656] BUG: unable to handle kernel paging request at be3a6008 [ 5.722693] IP: [<c106d6b4>] load_microcode_amd+0x24/0x3f0 [ 5.722716] *pdpt = 0000000000000000 *pde = 0000000000000000 because there was a valid initrd there but without valid microcode in it and the container check happened *after* the relocated ramdisk handling on 32-bit, which was clearly wrong. While at it, take care of the ramdisk relocation on both 32- and 64-bit as it is done on both. Also, comment what we're doing because this code is a bit tricky. Reported-and-tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1391460104-7261-1-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-01-31Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core debug changes from Ingo Molnar: "This contains mostly kernel debugging related updates: - make hung_task detection more configurable to distros - add final bits for x86 UV NMI debugging, with related KGDB changes - update the mailing-list of MAINTAINERS entries I'm involved with" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: hung_task: Display every hung task warning sysctl: Add neg_one as a standard constraint x86/uv/nmi, kgdb/kdb: Fix UV NMI handler when KDB not configured x86/uv/nmi: Fix Sparse warnings kgdb/kdb: Fix no KDB config problem MAINTAINERS: Restore "L: linux-kernel@vger.kernel.org" entries
2014-01-31Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull more KVM updates from Paolo Bonzini: "Second batch of KVM updates. Some minor x86 fixes, two s390 guest features that need some handling in the host, and all the PPC changes. The PPC changes include support for little-endian guests and enablement for new POWER8 features" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (45 commits) x86, kvm: correctly access the KVM_CPUID_FEATURES leaf at 0x40000101 x86, kvm: cache the base of the KVM cpuid leaves kvm: x86: move KVM_CAP_HYPERV_TIME outside #ifdef KVM: PPC: Book3S PR: Cope with doorbell interrupts KVM: PPC: Book3S HV: Add software abort codes for transactional memory KVM: PPC: Book3S HV: Add new state for transactional memory powerpc/Kconfig: Make TM select VSX and VMX KVM: PPC: Book3S HV: Basic little-endian guest support KVM: PPC: Book3S HV: Add support for DABRX register on POWER7 KVM: PPC: Book3S HV: Prepare for host using hypervisor doorbells KVM: PPC: Book3S HV: Handle new LPCR bits on POWER8 KVM: PPC: Book3S HV: Handle guest using doorbells for IPIs KVM: PPC: Book3S HV: Consolidate code that checks reason for wake from nap KVM: PPC: Book3S HV: Implement architecture compatibility modes for POWER8 KVM: PPC: Book3S HV: Add handler for HV facility unavailable KVM: PPC: Book3S HV: Flush the correct number of TLB sets on POWER8 KVM: PPC: Book3S HV: Context-switch new POWER8 SPRs KVM: PPC: Book3S HV: Align physical and virtual CPU thread numbers KVM: PPC: Book3S HV: Don't set DABR on POWER8 kvm/ppc: IRQ disabling cleanup ...
2014-01-30Merge branch 'x86-asmlinkage-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asmlinkage (LTO) changes from Peter Anvin: "This patchset adds more infrastructure for link time optimization (LTO). This patchset was pulled into my tree late because of a miscommunication (part of the patchset was picked up by other maintainers). However, the patchset is strictly build-related and seems to be okay in testing" * 'x86-asmlinkage-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, asmlinkage, xen: Fix type of NMI x86, asmlinkage, xen, kvm: Make {xen,kvm}_lock_spinning global and visible x86: Use inline assembler instead of global register variable to get sp x86, asmlinkage, paravirt: Make paravirt thunks global x86, asmlinkage, paravirt: Don't rely on local assembler labels x86, asmlinkage, lguest: Fix C functions used by inline assembler
2014-01-30x86, cpu hotplug: Fix stack frame warning in check_irq_vectors_for_cpu_disable()Prarit Bhargava
Further discussion here: http://marc.info/?l=linux-kernel&m=139073901101034&w=2 kbuild, 0day kernel build service, outputs the warning: arch/x86/kernel/irq.c:333:1: warning: the frame size of 2056 bytes is larger than 2048 bytes [-Wframe-larger-than=] because check_irq_vectors_for_cpu_disable() allocates two cpumasks on the stack. Fix this by moving the two cpumasks to a global file context. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Tested-by: David Rientjes <rientjes@google.com> Signed-off-by: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1390915331-27375-1-git-send-email-prarit@redhat.com Cc: Andi Kleen <ak@linux.intel.com> Cc: Michel Lespinasse <walken@google.com> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Cc: Yang Zhang <yang.z.zhang@Intel.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Janet Morgan <janet.morgan@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Ruiv Wang <ruiv.wang@gmail.com> Cc: Gong Chen <gong.chen@linux.intel.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-29x86, asmlinkage, xen, kvm: Make {xen,kvm}_lock_spinning global and visibleAndi Kleen
These functions are called from inline assembler stubs, thus need to be global and visible. Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1382458079-24450-7-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-29x86, asmlinkage, paravirt: Make paravirt thunks globalAndi Kleen
The paravirt thunks use a hack of using a static reference to a static function to reference that function from the top level statement. This assumes that gcc always generates static function names in a specific format, which is not necessarily true. Simply make these functions global and asmlinkage or __visible. This way the static __used variables are not needed and everything works. Functions with arguments are __visible to keep the register calling convention on 32bit. Changed in paravirt and in all users (Xen and vsmp) v2: Use __visible for functions with arguments Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Ido Yariv <ido@wizery.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1382458079-24450-5-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-29x86, kvm: correctly access the KVM_CPUID_FEATURES leaf at 0x40000101Paolo Bonzini
When Hyper-V hypervisor leaves are present, KVM must relocate its own leaves at 0x40000100, because Windows does not look for Hyper-V leaves at indices other than 0x40000000. In this case, the KVM features are at 0x40000101, but the old code would always look at 0x40000001. Fix by using kvm_cpuid_base(). This also requires making the function non-inline, since kvm_cpuid_base() is static. Fixes: 1085ba7f552d84aa8ac0ae903fa8d0cc2ff9f79d Cc: stable@vger.kernel.org Cc: mtosatti@redhat.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-01-29x86, kvm: cache the base of the KVM cpuid leavesPaolo Bonzini
It is unnecessary to go through hypervisor_cpuid_base every time a leaf is found (which will be every time a feature is requested after the next patch). Fixes: 1085ba7f552d84aa8ac0ae903fa8d0cc2ff9f79d Cc: stable@vger.kernel.org Cc: mtosatti@redhat.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-01-27x86: revert wrong memblock current limit settingYinghai Lu
Dave reported big numa system booting is broken. It turns out that commit 5b6e529521d3 ("x86: memblock: set current limit to max low memory address") sets the limit to low wrongly. max_low_pfn_mapped is different from max_pfn_mapped. max_low_pfn_mapped is always under 4G. That will memblock_alloc_nid all go under 4G. Revert 5b6e529521d3 to fix a no-boot regression which was triggered by 457ff1de2d24 ("lib/swiotlb.c: use memblock apis for early memory allocations"). Signed-off-by: Yinghai Lu <yinghai@kernel.org> Reported-by: Dave Hansen <dave.hansen@intel.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-25Merge 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: "A couple of regression fixes mostly hitting virtualized setups, but also some bare metal systems" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/x86/tsc: Initialize multiplier to 0 sched/clock: Fixup early initialization sched/preempt/x86: Fix voluntary preempt for x86 Revert "sched: Fix sleep time double accounting in enqueue entity"
2014-01-25Merge branch 'linus' into x86/urgentIngo Molnar
Merge in the x86 changes to apply a fix. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-01-25mm, x86: Revisit tlb_flushall_shift tuning for page flushes except on IvyBridgeMel Gorman
There was a large ebizzy performance regression that was bisected to commit 611ae8e3 (x86/tlb: enable tlb flush range support for x86). The problem was related to the tlb_flushall_shift tuning for IvyBridge which was altered. The problem is that it is not clear if the tuning values for each CPU family is correct as the methodology used to tune the values is unclear. This patch uses a conservative tlb_flushall_shift value for all CPU families except IvyBridge so the decision can be revisited if any regression is found as a result of this change. IvyBridge is an exception as testing with one methodology determined that the value of 2 is acceptable. Details are in the changelog for the patch "x86: mm: Change tlb_flushall_shift for IvyBridge". One important aspect of this to watch out for is Xen. The original commit log mentioned large performance gains on Xen. It's possible Xen is more sensitive to this value if it flushes small ranges of pages more frequently than workloads on bare metal typically do. Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Davidlohr Bueso <davidlohr@hp.com> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alex Shi <alex.shi@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-dyzMww3fqugnhbhgo6Gxmtkw@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-01-25x86: mm: change tlb_flushall_shift for IvyBridgeMel Gorman
There was a large performance regression that was bisected to commit 611ae8e3 ("x86/tlb: enable tlb flush range support for x86"). This patch simply changes the default balance point between a local and global flush for IvyBridge. In the interest of allowing the tests to be reproduced, this patch was tested using mmtests 0.15 with the following configurations configs/config-global-