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2013-04-25KVM: x86: Convert MSR_KVM_SYSTEM_TIME to use gfn_to_hva_cache functions ↵Andy Honig
(CVE-2013-1797) commit 0b79459b482e85cb7426aa7da683a9f2c97aeae1 upstream. There is a potential use after free issue with the handling of MSR_KVM_SYSTEM_TIME. If the guest specifies a GPA in a movable or removable memory such as frame buffers then KVM might continue to write to that address even after it's removed via KVM_SET_USER_MEMORY_REGION. KVM pins the page in memory so it's unlikely to cause an issue, but if the user space component re-purposes the memory previously used for the guest, then the guest will be able to corrupt that memory. Tested: Tested against kvmclock unit test Signed-off-by: Andrew Honig <ahonig@google.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-16x86, mm: Patch out arch_flush_lazy_mmu_mode() when running on bare metalBoris Ostrovsky
commit 511ba86e1d386f671084b5d0e6f110bb30b8eeb2 upstream. Invoking arch_flush_lazy_mmu_mode() results in calls to preempt_enable()/disable() which may have performance impact. Since lazy MMU is not used on bare metal we can patch away arch_flush_lazy_mmu_mode() so that it is never called in such environment. [ hpa: the previous patch "Fix vmalloc_fault oops during lazy MMU updates" may cause a minor performance regression on bare metal. This patch resolves that performance regression. It is somewhat unclear to me if this is a good -stable candidate. ] Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: http://lkml.kernel.org/r/1364045796-10720-2-git-send-email-konrad.wilk@oracle.com Tested-by: Josh Boyer <jwboyer@redhat.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-05signal: Define __ARCH_HAS_SA_RESTORER so we know whether to clear sa_restorerBen Hutchings
Vaguely based on upstream commit 574c4866e33d 'consolidate kernel-side struct sigaction declarations'. flush_signal_handlers() needs to know whether sigaction::sa_restorer is defined, not whether SA_RESTORER is defined. Define the __ARCH_HAS_SA_RESTORER macro to indicate this. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-28x86-32, mm: Remove reference to resume_map_numa_kva()H. Peter Anvin
commit bb112aec5ee41427e9b9726e3d57b896709598ed upstream. Remove reference to removed function resume_map_numa_kva(). Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20130131005616.1C79F411@kernel.stglabs.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-17x86/mm: Check if PUD is large when validating a kernel addressMel Gorman
commit 0ee364eb316348ddf3e0dfcd986f5f13f528f821 upstream. A user reported the following oops when a backup process reads /proc/kcore: BUG: unable to handle kernel paging request at ffffbb00ff33b000 IP: [<ffffffff8103157e>] kern_addr_valid+0xbe/0x110 [...] Call Trace: [<ffffffff811b8aaa>] read_kcore+0x17a/0x370 [<ffffffff811ad847>] proc_reg_read+0x77/0xc0 [<ffffffff81151687>] vfs_read+0xc7/0x130 [<ffffffff811517f3>] sys_read+0x53/0xa0 [<ffffffff81449692>] system_call_fastpath+0x16/0x1b Investigation determined that the bug triggered when reading system RAM at the 4G mark. On this system, that was the first address using 1G pages for the virt->phys direct mapping so the PUD is pointing to a physical address, not a PMD page. The problem is that the page table walker in kern_addr_valid() is not checking pud_large() and treats the physical address as if it was a PMD. If it happens to look like pmd_none then it'll silently fail, probably returning zeros instead of real data. If the data happens to look like a present PMD though, it will be walked resulting in the oops above. This patch adds the necessary pud_large() check. Unfortunately the problem was not readily reproducible and now they are running the backup program without accessing /proc/kcore so the patch has not been validated but I think it makes sense. Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.coM> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20130211145236.GX21389@suse.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-27x86: Use enum instead of literals for trap values [PARTIAL]Kees Cook
[Based on commit c94082656dac74257f63e91f78d5d458ac781fa5 upstream, only taking the traps.h portion.] The traps are referred to by their numbers and it can be difficult to understand them while reading the code without context. This patch adds enumeration of the trap numbers and replaces the numbers with the correct enum for x86. Signed-off-by: Kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/20120310000710.GA32667@www.outflux.net Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Robin Holt <holt@sgi.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-12-03x86-32: Fix invalid stack address while in softirqRobert Richter
commit 1022623842cb72ee4d0dbf02f6937f38c92c3f41 upstream. In 32 bit the stack address provided by kernel_stack_pointer() may point to an invalid range causing NULL pointer access or page faults while in NMI (see trace below). This happens if called in softirq context and if the stack is empty. The address at &regs->sp is then out of range. Fixing this by checking if regs and &regs->sp are in the same stack context. Otherwise return the previous stack pointer stored in struct thread_info. If that address is invalid too, return address of regs. BUG: unable to handle kernel NULL pointer dereference at 0000000a IP: [<c1004237>] print_context_stack+0x6e/0x8d *pde = 00000000 Oops: 0000 [#1] SMP Modules linked in: Pid: 4434, comm: perl Not tainted 3.6.0-rc3-oprofile-i386-standard-g4411a05 #4 Hewlett-Packard HP xw9400 Workstation/0A1Ch EIP: 0060:[<c1004237>] EFLAGS: 00010093 CPU: 0 EIP is at print_context_stack+0x6e/0x8d EAX: ffffe000 EBX: 0000000a ECX: f4435f94 EDX: 0000000a ESI: f4435f94 EDI: f4435f94 EBP: f5409ec0 ESP: f5409ea0 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 CR0: 8005003b CR2: 0000000a CR3: 34ac9000 CR4: 000007d0 DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 DR6: ffff0ff0 DR7: 00000400 Process perl (pid: 4434, ti=f5408000 task=f5637850 task.ti=f4434000) Stack: 000003e8 ffffe000 00001ffc f4e39b00 00000000 0000000a f4435f94 c155198c f5409ef0 c1003723 c155198c f5409f04 00000000 f5409edc 00000000 00000000 f5409ee8 f4435f94 f5409fc4 00000001 f5409f1c c12dce1c 00000000 c155198c Call Trace: [<c1003723>] dump_trace+0x7b/0xa1 [<c12dce1c>] x86_backtrace+0x40/0x88 [<c12db712>] ? oprofile_add_sample+0x56/0x84 [<c12db731>] oprofile_add_sample+0x75/0x84 [<c12ddb5b>] op_amd_check_ctrs+0x46/0x260 [<c12dd40d>] profile_exceptions_notify+0x23/0x4c [<c1395034>] nmi_handle+0x31/0x4a [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c13950ed>] do_nmi+0xa0/0x2ff [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c13949e5>] nmi_stack_correct+0x28/0x2d [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c1003603>] ? do_softirq+0x4b/0x7f <IRQ> [<c102a06f>] irq_exit+0x35/0x5b [<c1018f56>] smp_apic_timer_interrupt+0x6c/0x7a [<c1394746>] apic_timer_interrupt+0x2a/0x30 Code: 89 fe eb 08 31 c9 8b 45 0c ff 55 ec 83 c3 04 83 7d 10 00 74 0c 3b 5d 10 73 26 3b 5d e4 73 0c eb 1f 3b 5d f0 76 1a 3b 5d e8 73 15 <8b> 13 89 d0 89 55 e0 e8 ad 42 03 00 85 c0 8b 55 e0 75 a6 eb cc EIP: [<c1004237>] print_context_stack+0x6e/0x8d SS:ESP 0068:f5409ea0 CR2: 000000000000000a ---[ end trace 62afee3481b00012 ]--- Kernel panic - not syncing: Fatal exception in interrupt V2: * add comments to kernel_stack_pointer() * always return a valid stack address by falling back to the address of regs Reported-by: Yang Wei <wei.yang@windriver.com> Signed-off-by: Robert Richter <robert.richter@amd.com> Link: http://lkml.kernel.org/r/20120912135059.GZ8285@erda.amd.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Jun Zhang <jun.zhang@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-05x86: Remove the ancient and deprecated disable_hlt() and enable_hlt() facilityLen Brown
commit f6365201d8a21fb347260f89d6e9b3e718d63c70 upstream. The X86_32-only disable_hlt/enable_hlt mechanism was used by the 32-bit floppy driver. Its effect was to replace the use of the HLT instruction inside default_idle() with cpu_relax() - essentially it turned off the use of HLT. This workaround was commented in the code as: "disable hlt during certain critical i/o operations" "This halt magic was a workaround for ancient floppy DMA wreckage. It should be safe to remove." H. Peter Anvin additionally adds: "To the best of my knowledge, no-hlt only existed because of flaky power distributions on 386/486 systems which were sold to run DOS. Since DOS did no power management of any kind, including HLT, the power draw was fairly uniform; when exposed to the much hhigher noise levels you got when Linux used HLT caused some of these systems to fail. They were by far in the minority even back then." Alan Cox further says: "Also for the Cyrix 5510 which tended to go castors up if a HLT occurred during a DMA cycle and on a few other boxes HLT during DMA tended to go astray. Do we care ? I doubt it. The 5510 was pretty obscure, the 5520 fixed it, the 5530 is probably the oldest still in any kind of use." So, let's finally drop this. Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Josh Boyer <jwboyer@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Stephen Hemminger <shemminger@vyatta.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/n/tip-3rhk9bzf0x9rljkv488tloib@git.kernel.org [ If anyone cares then alternative instruction patching could be used to replace HLT with a one-byte NOP instruction. Much simpler. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-21x86, random: Verify RDRAND functionality and allow it to be disabledH. Peter Anvin
commit 49d859d78c5aeb998b6936fcb5f288f78d713489 upstream. If the CPU declares that RDRAND is available, go through a guranteed reseed sequence, and make sure that it is actually working (producing data.) If it does not, disable the CPU feature flag. Allow RDRAND to be disabled on the command line (as opposed to at compile time) for a user who has special requirements with regards to random numbers. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Matt Mackall <mpm@selenic.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-21x86, random: Architectural inlines to get random integers with RDRANDH. Peter Anvin
commit 628c6246d47b85f5357298601df2444d7f4dd3fd upstream. Architectural inlines to get random ints and longs using the RDRAND instruction. Intel has introduced a new RDRAND instruction, a Digital Random Number Generator (DRNG), which is functionally an high bandwidth entropy source, cryptographic whitener, and integrity monitor all built into hardware. This enables RDRAND to be used directly, bypassing the kernel random number pool. For technical documentation, see: http://software.intel.com/en-us/articles/download-the-latest-bull-mountain-software-implementation-guide/ In this patch, this is *only* used for the nonblocking random number pool. RDRAND is a nonblocking source, similar to our /dev/urandom, and is therefore not a direct replacement for /dev/random. The architectural hooks presented in the previous patch only feed the kernel internal users, which only use the nonblocking pool, and so this is not a problem. Since this instruction is available in userspace, there is no reason to have a /dev/hw_rng device driver for the purpose of feeding rngd. This is especially so since RDRAND is a nonblocking source, and needs additional whitening and reduction (see the above technical documentation for details) in order to be of "pure entropy source" quality. The CONFIG_EXPERT compile-time option can be used to disable this use of RDRAND. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Originally-by: Fenghua Yu <fenghua.yu@intel.com> Cc: Matt Mackall <mpm@selenic.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-13mm: thp: fix pmd_present for split_huge_page and PROT_NONE with THPAndrea Arcangeli
commit 027ef6c87853b0a9df53175063028edb4950d476 upstream. In many places !pmd_present has been converted to pmd_none. For pmds that's equivalent and pmd_none is quicker so using pmd_none is better. However (unless we delete pmd_present) we should provide an accurate pmd_present too. This will avoid the risk of code thinking the pmd is non present because it's under __split_huge_page_map, see the pmd_mknotpresent there and the comment above it. If the page has been mprotected as PROT_NONE, it would also lead to a pmd_present false negative in the same way as the race with split_huge_page. Because the PSE bit stays on at all times (both during split_huge_page and when the _PAGE_PROTNONE bit get set), we could only check for the PSE bit, but checking the PROTNONE bit too is still good to remember pmd_present must always keep PROT_NONE into account. This explains a not reproducible BUG_ON that was seldom reported on the lists. The same issue is in pmd_large, it would go wrong with both PROT_NONE and if it races with split_huge_page. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <jweiner@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-15x86: Simplify code by removing a !SMP #ifdefs from 'struct cpuinfo_x86'Kevin Winchester
commit 141168c36cdee3ff23d9c7700b0edc47cb65479f and commit 3f806e50981825fa56a7f1938f24c0680816be45 upstream. Several fields in struct cpuinfo_x86 were not defined for the !SMP case, likely to save space. However, those fields still have some meaning for UP, and keeping them allows some #ifdef removal from other files. The additional size of the UP kernel from this change is not significant enough to worry about keeping up the distinction: text data bss dec hex filename 4737168 506459 972040 6215667 5ed7f3 vmlinux.o.before 4737444 506459 972040 6215943 5ed907 vmlinux.o.after for a difference of 276 bytes for an example UP config. If someone wants those 276 bytes back badly then it should be implemented in a cleaner way. Signed-off-by: Kevin Winchester <kjwinchester@gmail.com> Cc: Steffen Persvold <sp@numascale.com> Link: http://lkml.kernel.org/r/1324428742-12498-1-git-send-email-kjwinchester@gmail.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16x86, cpufeature: Rename X86_FEATURE_DTS to X86_FEATURE_DTHERMH. Peter Anvin
commit 4ad33411308596f2f918603509729922a1ec4411 upstream. It makes sense to label "Digital Thermal Sensor" as "DTS", but unfortunately the string "dts" was already used for "Debug Store", and /proc/cpuinfo is a user space ABI. Therefore, rename this to "dtherm". This conflict went into mainline via the hwmon tree without any x86 maintainer ack, and without any kind of hint in the subject. a4659053 x86/hwmon: fix initialization of coretemp Reported-by: Jean Delvare <khali@linux-fr.org> Link: http://lkml.kernel.org/r/4FE34BCB.5050305@linux.intel.com Cc: Jan Beulich <JBeulich@suse.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> [bwh: Backported to 3.2: drop the coretemp device table change] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-10mm: pmd_read_atomic: fix 32bit PAE pmd walk vs pmd_populate SMP race conditionAndrea Arcangeli
commit 26c191788f18129af0eb32a358cdaea0c7479626 upstream. When holding the mmap_sem for reading, pmd_offset_map_lock should only run on a pmd_t that has been read atomically from the pmdp pointer, otherwise we may read only half of it leading to this crash. PID: 11679 TASK: f06e8000 CPU: 3 COMMAND: "do_race_2_panic" #0 [f06a9dd8] crash_kexec at c049b5ec #1 [f06a9e2c] oops_end at c083d1c2 #2 [f06a9e40] no_context at c0433ded #3 [f06a9e64] bad_area_nosemaphore at c043401a #4 [f06a9e6c] __do_page_fault at c0434493 #5 [f06a9eec] do_page_fault at c083eb45 #6 [f06a9f04] error_code (via page_fault) at c083c5d5 EAX: 01fb470c EBX: fff35000 ECX: 00000003 EDX: 00000100 EBP: 00000000 DS: 007b ESI: 9e201000 ES: 007b EDI: 01fb4700 GS: 00e0 CS: 0060 EIP: c083bc14 ERR: ffffffff EFLAGS: 00010246 #7 [f06a9f38] _spin_lock at c083bc14 #8 [f06a9f44] sys_mincore at c0507b7d #9 [f06a9fb0] system_call at c083becd start len EAX: ffffffda EBX: 9e200000 ECX: 00001000 EDX: 6228537f DS: 007b ESI: 00000000 ES: 007b EDI: 003d0f00 SS: 007b ESP: 62285354 EBP: 62285388 GS: 0033 CS: 0073 EIP: 00291416 ERR: 000000da EFLAGS: 00000286 This should be a longstanding bug affecting x86 32bit PAE without THP. Only archs with 64bit large pmd_t and 32bit unsigned long should be affected. With THP enabled the barrier() in pmd_none_or_trans_huge_or_clear_bad() would partly hide the bug when the pmd transition from none to stable, by forcing a re-read of the *pmd in pmd_offset_map_lock, but when THP is enabled a new set of problem arises by the fact could then transition freely in any of the none, pmd_trans_huge or pmd_trans_stable states. So making the barrier in pmd_none_or_trans_huge_or_clear_bad() unconditional isn't good idea and it would be a flakey solution. This should be fully fixed by introducing a pmd_read_atomic that reads the pmd in order with THP disabled, or by reading the pmd atomically with cmpxchg8b with THP enabled. Luckily this new race condition only triggers in the places that must already be covered by pmd_none_or_trans_huge_or_clear_bad() so the fix is localized there but this bug is not related to THP. NOTE: this can trigger on x86 32bit systems with PAE enabled with more than 4G of ram, otherwise the high part of the pmd will never risk to be truncated because it would be zero at all times, in turn so hiding the SMP race. This bug was discovered and fully debugged by Ulrich, quote: ---- [..] pmd_none_or_trans_huge_or_clear_bad() loads the content of edx and eax. 496 static inline int pmd_none_or_trans_huge_or_clear_bad(pmd_t *pmd) 497 { 498 /* depend on compiler for an atomic pmd read */ 499 pmd_t pmdval = *pmd; // edi = pmd pointer 0xc0507a74 <sys_mincore+548>: mov 0x8(%esp),%edi ... // edx = PTE page table high address 0xc0507a84 <sys_mincore+564>: mov 0x4(%edi),%edx ... // eax = PTE page table low address 0xc0507a8e <sys_mincore+574>: mov (%edi),%eax [..] Please note that the PMD is not read atomically. These are two "mov" instructions where the high order bits of the PMD entry are fetched first. Hence, the above machine code is prone to the following race. - The PMD entry {high|low} is 0x0000000000000000. The "mov" at 0xc0507a84 loads 0x00000000 into edx. - A page fault (on another CPU) sneaks in between the two "mov" instructions and instantiates the PMD. - The PMD entry {high|low} is now 0x00000003fda38067. The "mov" at 0xc0507a8e loads 0xfda38067 into eax. ---- Reported-by: Ulrich Obergfell <uobergfe@redhat.com> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Petr Matousek <pmatouse@redhat.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-13sched/x86: Fix overflow in cyc2ns_offsetSalman Qazi
commit 9993bc635d01a6ee7f6b833b4ee65ce7c06350b1 upstream. When a machine boots up, the TSC generally gets reset. However, when kexec is used to boot into a kernel, the TSC value would be carried over from the previous kernel. The computation of cycns_offset in set_cyc2ns_scale is prone to an overflow, if the machine has been up more than 208 days prior to the kexec. The overflow happens when we multiply *scale, even though there is enough room to store the final answer. We fix this issue by decomposing tsc_now into the quotient and remainder of division by CYC2NS_SCALE_FACTOR and then performing the multiplication separately on the two components. Refactor code to share the calculation with the previous fix in __cycles_2_ns(). Signed-off-by: Salman Qazi <sqazi@google.com> Acked-by: John Stultz <john.stultz@linaro.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Turner <pjt@google.com> Cc: john stultz <johnstul@us.ibm.com> Link: http://lkml.kernel.org/r/20120310004027.19291.88460.stgit@dungbeetle.mtv.corp.google.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-02KVM: x86: fix missing checks in syscall emulationStephan Bärwolf
commit c2226fc9e87ba3da060e47333657cd6616652b84 upstream. On hosts without this patch, 32bit guests will crash (and 64bit guests may behave in a wrong way) for example by simply executing following nasm-demo-application: [bits 32] global _start SECTION .text _start: syscall (I tested it with winxp and linux - both always crashed) Disassembly of section .text: 00000000 <_start>: 0: 0f 05 syscall The reason seems a missing "invalid opcode"-trap (int6) for the syscall opcode "0f05", which is not available on Intel CPUs within non-longmodes, as also on some AMD CPUs within legacy-mode. (depending on CPU vendor, MSR_EFER and cpuid) Because previous mentioned OSs may not engage corresponding syscall target-registers (STAR, LSTAR, CSTAR), they remain NULL and (non trapping) syscalls are leading to multiple faults and finally crashs. Depending on the architecture (AMD or Intel) pretended by guests, various checks according to vendor's documentation are implemented to overcome the current issue and behave like the CPUs physical counterparts. [mtosatti: cleanup/beautify code] Signed-off-by: Stephan Baerwolf <stephan.baerwolf@tu-ilmenau.de> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-02KVM: x86: extend "struct x86_emulate_ops" with "get_cpuid"Stephan Bärwolf
commit bdb42f5afebe208eae90406959383856ae2caf2b upstream. In order to be able to proceed checks on CPU-specific properties within the emulator, function "get_cpuid" is introduced. With "get_cpuid" it is possible to virtually call the guests "cpuid"-opcode without changing the VM's context. [mtosatti: cleanup/beautify code] Signed-off-by: Stephan Baerwolf <stephan.baerwolf@tu-ilmenau.de> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-29i387: re-introduce FPU state preloading at context switch timeLinus Torvalds
commit 34ddc81a230b15c0e345b6b253049db731499f7e upstream. After all the FPU state cleanups and finally finding the problem that caused all our FPU save/restore problems, this re-introduces the preloading of FPU state that was removed in commit b3b0870ef3ff ("i387: do not preload FPU state at task switch time"). However, instead of simply reverting the removal, this reimplements preloading with several fixes, most notably - properly abstracted as a true FPU state switch, rather than as open-coded save and restore with various hacks. In particular, implementing it as a proper FPU state switch allows us to optimize the CR0.TS flag accesses: there is no reason to set the TS bit only to then almost immediately clear it again. CR0 accesses are quite slow and expensive, don't flip the bit back and forth for no good reason. - Make sure that the same model works for both x86-32 and x86-64, so that there are no gratuitous differences between the two due to the way they save and restore segment state differently due to architectural differences that really don't matter to the FPU state. - Avoid exposing the "preload" state to the context switch routines, and in particular allow the concept of lazy state restore: if nothing else has used the FPU in the meantime, and the process is still on the same CPU, we can avoid restoring state from memory entirely, just re-expose the state that is still in the FPU unit. That optimized lazy restore isn't actually implemented here, but the infrastructure is set up for it. Of course, older CPU's that use 'fnsave' to save the state cannot take advantage of this, since the state saving also trashes the state. In other words, there is now an actual _design_ to the FPU state saving, rather than just random historical baggage. Hopefully it's easier to follow as a result. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-29i387: move TS_USEDFPU flag from thread_info to task_structLinus Torvalds
commit f94edacf998516ac9d849f7bc6949a703977a7f3 upstream. This moves the bit that indicates whether a thread has ownership of the FPU from the TS_USEDFPU bit in thread_info->status to a word of its own (called 'has_fpu') in task_struct->thread.has_fpu. This fixes two independent bugs at the same time: - changing 'thread_info->status' from the scheduler causes nasty problems for the other users of that variable, since it is defined to be thread-synchronous (that's what the "TS_" part of the naming was supposed to indicate). So perfectly valid code could (and did) do ti->status |= TS_RESTORE_SIGMASK; and the compiler was free to do that as separate load, or and store instructions. Which can cause problems with preemption, since a task switch could happen in between, and change the TS_USEDFPU bit. The change to TS_USEDFPU would be overwritten by the final store. In practice, this seldom happened, though, because the 'status' field was seldom used more than once, so gcc would generally tend to generate code that used a read-modify-write instruction and thus happened to avoid this problem - RMW instructions are naturally low fat and preemption-safe. - On x86-32, the current_thread_info() pointer would, during interrupts and softirqs, point to a *copy* of the real thread_info, because x86-32 uses %esp to calculate the thread_info address, and thus the separate irq (and softirq) stacks would cause these kinds of odd thread_info copy aliases. This is normally not a problem, since interrupts aren't supposed to look at thread information anyway (what thread is running at interrupt time really isn't very well-defined), but it confused the heck out of irq_fpu_usable() and the code that tried to squirrel away the FPU state. (It also caused untold confusion for us poor kernel developers). It also turns out that using 'task_struct' is actually much more natural for most of the call sites that care about the FPU state, since they tend to work with the task struct for other reasons anyway (ie scheduling). And the FPU data that we are going to save/restore is found there too. Thanks to Arjan Van De Ven <arjan@linux.intel.com> for pointing us to the %esp issue. Cc: Arjan van de Ven <arjan@linux.intel.com> Reported-and-tested-by: Raphael Prevost <raphael@buro.asia> Acked-and-tested-by: Suresh Siddha <suresh.b.siddha@intel.com> Tested-by: Peter Anvin <hpa@zytor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-29i387: move AMD K7/K8 fpu fxsave/fxrstor workaround from save to restoreLinus Torvalds
commit 4903062b5485f0e2c286a23b44c9b59d9b017d53 upstream. The AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception is pending. In order to not leak FIP state from one process to another, we need to do a floating point load after the fxsave of the old process, and before the fxrstor of the new FPU state. That resets the state to the (uninteresting) kernel load, rather than some potentially sensitive user information. We used to do this directly after the FPU state save, but that is actually very inconvenient, since it (a) corrupts what is potentially perfectly good FPU state that we might want to lazy avoid restoring later and (b) on x86-64 it resulted in a very annoying ordering constraint, where "__unlazy_fpu()" in the task switch needs to be delayed until after the DS segment has been reloaded just to get the new DS value. Coupling it to the fxrstor instead of the fxsave automatically avoids both of these issues, and also ensures that we only do it when actually necessary (the FP state after a save may never actually get used). It's simply a much more natural place for the leaked state cleanup. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-29i387: do not preload FPU state at task switch timeLinus Torvalds
commit b3b0870ef3ffed72b92415423da864f440f57ad6 upstream. Yes, taking the trap to re-load the FPU/MMX state is expensive, but so is spending several days looking for a bug in the state save/restore code. And the preload code has some rather subtle interactions with both paravirtualization support and segment state restore, so it's not nearly as simple as it should be. Also, now that we no longer necessarily depend on a single bit (ie TS_USEDFPU) for keeping track of the state of the FPU, we migth be able to do better. If we are really switching between two processes that keep touching the FP state, save/restore is inevitable, but in the case of having one process that does most of the FPU usage, we may actually be able to do much better than the preloading. In particular, we may be able to keep track of which CPU the process ran on last, and also per CPU keep track of which process' FP state that CPU has. For modern CPU's that don't destroy the FPU contents on save time, that would allow us to do a lazy restore by just re-enabling the existing FPU state - with no restore cost at all! Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-29i387: don't ever touch TS_USEDFPU directly, use helper functionsLinus Torvalds
commit 6d59d7a9f5b723a7ac1925c136e93ec83c0c3043 upstream. This creates three helper functions that do the TS_USEDFPU accesses, and makes everybody that used to do it by hand use those helpers instead. In addition, there's a couple of helper functions for the "change both CR0.TS and TS_USEDFPU at the same time" case, and the places that do that together have been changed to use those. That means that we have fewer random places that open-code this situation. The intent is partly to clarify the code without actually changing any semantics yet (since we clearly still have some hard to reproduce bug in this area), but also to make it much easier to use another approach entirely to caching the CR0.TS bit for software accesses. Right now we use a bit in the thread-info 'status' variable (this patch does not change that), but we might want to make it a full field of its own or even make it a per-cpu variable. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-29i387: move TS_USEDFPU clearing out of __save_init_fpu and into callersLinus Torvalds
commit b6c66418dcad0fcf83cd1d0a39482db37bf4fc41 upstream. Touching TS_USEDFPU without touching CR0.TS is confusing, so don't do it. By moving it into the callers, we always do the TS_USEDFPU next to the CR0.TS accesses in the source code, and it's much easier to see how the two go hand in hand. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-29i387: fix x86-64 preemption-unsafe user stack save/restoreLinus Torvalds
commit 15d8791cae75dca27bfda8ecfe87dca9379d6bb0 upstream. Commit 5b1cbac37798 ("i387: make irq_fpu_usable() tests more robust") added a sanity check to the #NM handler to verify that we never cause the "Device Not Available" exception in kernel mode. However, that check actually pinpointed a (fundamental) race where we do cause that exception as part of the signal stack FPU state save/restore code. Because we use the floating point instructions themselves to save and restore state directly from user mode, we cannot do that atomically with testing the TS_USEDFPU bit: the user mode access itself may cause a page fault, which causes a task switch, which saves and restores the FP/MMX state from the kernel buffers. This kind of "recursive" FP state save is fine per se, but it means that when the signal stack save/restore gets restarted, it will now take the '#NM' exception we originally tried to avoid. With preemption this can happen even without the page fault - but because of the user access, we cannot just disable preemption around the save/restore instruction. There are various ways to solve this, including using the "enable/disable_page_fault()" helpers to not allow page faults at all during the sequence, and fall back to copying things by hand without the use of the native FP state save/restore instructions. However, the simplest thing to do is to just allow the #NM from kernel space, but fix the race in setting and clearing CR0.TS that this all exposed: the TS bit changes and the TS_USEDFPU bit absolutely have to be atomic wrt scheduling, so while the actual state save/restore can be interrupted and restarted, the act of actually clearing/setting CR0.TS and the TS_USEDFPU bit together must not. Instead of just adding random "preempt_disable/enable()" calls to what is already excessively ugly code, this introduces some helper functions that mostly mirror the "kernel_fpu_begin/end()" functionality, just for the user state instead. Those helper functions should probably eventually replace the other ad-hoc CR0.TS and TS_USEDFPU tests too, but I'll need to think about it some more: the task switching functionality in particular needs to expose the difference between the 'prev' and 'next' threads, while the new helper functions intentionally were written to only work with 'current'. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-29i387: fix sense of sanity checkLinus Torvalds
commit c38e23456278e967f094b08247ffc3711b1029b2 upstream. The check for save_init_fpu() (introduced in commit 5b1cbac37798: "i387: make irq_fpu_usable() tests more robust") was the wrong way around, but I hadn't noticed, because my "tests" were bogus: the FPU exceptions are disabled by default, so even doing a divide by zero never actually triggers this code at all unless you do extra work to enable them. So if anybody did enable them, they'd get one spurious warning. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-29i387: make irq_fpu_usable() tests more robustLinus Torvalds
commit 5b1cbac37798805c1fee18c8cebe5c0a13975b17 upstream. Some code - especially the crypto layer - wants to use the x86 FP/MMX/AVX register set in what may be interrupt (typically softirq) context. That *can* be ok, but the tests for when it was ok were somewhat suspect. We cannot touch the thread-specific status bits either, so we'd better check that we're not going to try to save FP state or anything like that. Now, it may be that the TS bit is always cleared *before* we set the USEDFPU bit (and only set when we had already cleared the USEDFP before), so the TS bit test may actually have been sufficient, but it certainly was not obviously so. So this explicitly verifies that we will not touch the TS_USEDFPU bit, and adds a few related sanity-checks. Because it seems that somehow AES-NI is corrupting user FP state. The cause is not clear, and this patch doesn't fix it, but while debugging it I really wanted the code to be more obviously correct and robust. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-29i387: math_state_restore() isn't called from asmLinus Torvalds
commit be98c2cdb15ba26148cd2bd58a857d4f7759ed38 upstream. It was marked asmlinkage for some really old and stale legacy reasons. Fix that and the equally stale comment. Noticed when debugging the irq_fpu_usable() bugs. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-03x86/uv: Fix uv_gpa_to_soc_phys_ram() shiftRuss Anderson
commit 5a51467b146ab7948d2f6812892eac120a30529c upstream. uv_gpa_to_soc_phys_ram() was inadvertently ignoring the shift values. This fix takes the shift into account. Signed-off-by: Russ Anderson <rja@sgi.com> Link: http://lkml.kernel.org/r/20120119020753.GA7228@sgi.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-01-25x86/PCI: amd: factor out MMCONFIG discoveryBjorn Helgaas
commit 24d25dbfa63c376323096660bfa9ad45a08870ce upstream. This factors out the AMD native MMCONFIG discovery so we can use it outside amd_bus.c. amd_bus.c reads AMD MSRs so it can remove the MMCONFIG area from the PCI resources. We may also need the MMCONFIG information to work around BIOS defects in the ACPI MCFG table. Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-12-09sched, x86: Avoid unnecessary overflow in sched_clockSalman Qazi
commit 4cecf6d401a01d054afc1e5f605bcbfe553cb9b9 upstream. (Added the missing signed-off-by line) In hundreds of days, the __cycles_2_ns calculation in sched_clock has an overflow. cyc * per_cpu(cyc2ns, cpu) exceeds 64 bits, causing the final value to become zero. We can solve this without losing any precision. We can decompose TSC into quotient and remainder of division by the scale factor, and then use this to convert TSC into nanoseconds. Signed-off-by: Salman Qazi <sqazi@google.com> Acked-by: John Stultz <johnstul@us.ibm.com> Reviewed-by: Paul Turner <pjt@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20111115221121.7262.88871.stgit@dungbeetle.mtv.corp.google.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-11apic, i386/bigsmp: Fix false warnings regarding logical APIC ID mismatchesJan Beulich
commit 838312be46f3abfbdc175f81c3e54a857994476d upstream. These warnings (generally one per CPU) are a result of initializing x86_cpu_to_logical_apicid while apic_default is still in use, but the check in setup_local_APIC() being done when apic_bigsmp was already used as an override in default_setup_apic_routing(): Overriding APIC driver with bigsmp Enabling APIC mode: Physflat. Using 5 I/O APICs ------------[ cut here ]------------ WARNING: at .../arch/x86/kernel/apic/apic.c:1239 ... CPU 1 irqstacks, hard=f1c9a000 soft=f1c9c000 Booting Node 0, Processors #1 smpboot cpu 1: start_ip = 9e000 Initializing CPU#1 ------------[ cut here ]------------ WARNING: at .../arch/x86/kernel/apic/apic.c:1239 setup_local_APIC+0x137/0x46b() Hardware name: ... CPU1 logical APIC ID: 2 != 8 ... Fix this (for the time being, i.e. until x86_32_early_logical_apicid() will get removed again, as Tejun says ought to be possible) by overriding the previously stored values at the point where the APIC driver gets overridden. v2: Move this and the pre-existing override logic into arch/x86/kernel/apic/bigsmp_32.c. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Tejun Heo <tj@kernel.org> Link: http://lkml.kernel.org/r/4E835D16020000780005844C@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-11x86: uv2: Workaround for UV2 Hub bug (system global address format)Jack Steiner
commit 6a469e4665bc158599de55d64388861d0a9f10f4 upstream. This is a workaround for a UV2 hub bug that affects the format of system global addresses. The GRU API for UV2 was inadvertently broken by a hardware change. The format of the physical address used for TLB dropins and for addresses used with instructions running in unmapped mode has changed. This change was not documented and became apparent only when diags failed running on system simulators. For UV1, TLB and GRU instruction physical addresses are identical to socket physical addresses (although high NASID bits must be OR'ed into the address). For UV2, socket physical addresses need to be converted. The NODE portion of the physical address needs to be shifted so that the low bit is in bit 39 or bit 40, depending on an MMR value. It is not yet clear if this bug will be fixed in a silicon respin. If it is fixed, the hub revision will be incremented & the workaround disabled. Signed-off-by: Jack Steiner <steiner@sgi.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: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-29xen/x86: replace order-based range checking of M2P table by linear oneJan Beulich
commit ccbcdf7cf1b5f6c6db30d84095b9c6c53043af55 upstream. The order-based approach is not only less efficient (requiring a shift and a compare, typical generated code looking like this mov eax, [machine_to_phys_order] mov ecx, eax shr ebx, cl test ebx, ebx jnz ... whereas a direct check requires just a compare, like in cmp ebx, [machine_to_phys_nr] jae ... ), but also slightly dangerous in the 32-on-64 case - the element address calculation can wrap if the next power of two boundary is sufficiently far away from the actual upper limit of the table, and hence can result in user space addresses being accessed (with it being unknown what may actually be mapped there). Additionally, the elimination of the mistaken use of fls() here (should have been __fls()) fixes a latent issue on x86-64 that would trigger if the code was run on a system with memory extending beyond the 44-bit boundary. Signed-off-by: Jan Beulich <jbeulich@novell.com> [v1: Based on Jeremy's feedback] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-04x86, intel, power: Initialize MSR_IA32_ENERGY_PERF_BIASLen Brown
commit abe48b108247e9b90b4c6739662a2e5c765ed114 upstream. Since 2.6.36 (23016bf0d25), Linux prints the existence of "epb" in /proc/cpuinfo, Since 2.6.38 (d5532ee7b40), the x86_energy_perf_policy(8) utility has been available in-tree to update MSR_IA32_ENERGY_PERF_BIAS. However, the typical BIOS fails to initialize the MSR, presumably because this is handled by high-volume shrink-wrap operating systems... Linux distros, on the other hand, do not yet invoke x86_energy_perf_policy(8). As a result, WSM-EP, SNB, and later hardware from Intel will run in its default hardware power-on state (performance), which assumes that users care for performance at all costs and not for energy efficiency. While that is fine for performance benchmarks, the hardware's intended default operating point is "normal" mode... Initialize the MSR to the "normal" by default during kernel boot. x86_energy_perf_policy(8) is available to change the default after boot, should the user have a different preference. Signed-off-by: Len Brown <len.brown@intel.com> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1107140051020.18606@x980 Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-07-01x86-32, NUMA: Fix boot regression caused by NUMA init unification on highmem ↵Tejun Heo
machines During 32/64 NUMA init unification, commit 797390d855 ("x86-32, NUMA: use sparse_memory_present_with_active_regions()") made 32bit mm init call memory_present() automatically from active_regions instead of leaving it to each NUMA init path. This commit description is inaccurate - memory_present() calls aren't the same for flat and numaq. After the commit, memory_present() is only called for the intersection of e820 and NUMA layout. Before, on flatmem, memory_present() would be called from 0 to max_pfn. After, it would be called only on the areas that e820 indicates to be populated. This is how x86_64 works and should be okay as memmap is allowed to contain holes; however, x86_32 DISCONTIGMEM is missing early_pfn_valid(), which makes memmap_init_zone() assume that memmap doesn't contain any hole. This leads to the following oops if e820 map contains holes as it often does on machine with near or more 4GiB of memory by calling pfn_to_page() on a pfn which isn't mapped to a NUMA node, a reported by Conny Seidel: BUG: unable to handle kernel paging request at 000012b0 IP: [<c1aa13ce>] memmap_init_zone+0x6c/0xf2 *pdpt =3D 0000000000000000 *pde =3D f000eef3f000ee00 Oops: 0000 [#1] SMP last sysfs file: Modules linked in: Pid: 0, comm: swapper Not tainted 2.6.39-rc5-00164-g797390d #1 To Be Filled By O.E.M. To Be Filled By O.E.M./E350M1 EIP: 0060:[<c1aa13ce>] EFLAGS: 00010012 CPU: 0 EIP is at memmap_init_zone+0x6c/0xf2 EAX: 00000000 EBX: 000a8000 ECX: 000a7fff EDX: f2c00b80 ESI: 000a8000 EDI: f2c00800 EBP: c19ffe54 ESP: c19ffe34 DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 Process swapper (pid: 0, ti=3Dc19fe000 task=3Dc1a07f60 task.ti=3Dc19fe000) Stack: 00000002 00000000 0023f000 00000000 10000000 00000a00 f2c00000 f2c00b58 c19ffeb0 c1a80f24 000375fe 00000000 f2c00800 00000800 00000100 00000030 c1abb768 0000003c 00000000 00000000 00000004 00207a02 f2c00800 000375fe Call Trace: [<c1a80f24>] free_area_init_node+0x358/0x385 [<c1a81384>] free_area_init_nodes+0x420/0x487 [<c1a79326>] paging_init+0x114/0x11b [<c1a6cb13>] setup_arch+0xb37/0xc0a [<c1a69554>] start_kernel+0x76/0x316 [<c1a690a8>] i386_start_kernel+0xa8/0xb0 This patch fixes the bug by defining early_pfn_valid() to be the same as pfn_valid() when DISCONTIGMEM. Reported-bisected-and-tested-by: Conny Seidel <conny.seidel@amd.com> Signed-off-by: Tejun Heo <tj@kernel.org> Cc: hans.rosenfeld@amd.com Cc: Christoph Lameter <cl@linux.com> Cc: Conny Seidel <conny.seidel@amd.com> Link: http://lkml.kernel.org/r/20110628094107.GB3386@htj.dyndns.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-06-28watchdog: Intel SCU Watchdog: Fix build and remove duplicate codeJesper Juhl
Trying to build the Intel SCU Watchdog fails for me with gcc 4.6.0 - $ gcc --version | head -n 1 gcc (GCC) 4.6.0 20110513 (prerelease) like this : CC drivers/watchdog/intel_scu_watchdog.o In file included from drivers/watchdog/intel_scu_watchdog.c:49:0: /home/jj/src/linux-2.6/arch/x86/include/asm/apb_timer.h: In function ‘apbt_time_init’: /home/jj/src/linux-2.6/arch/x86/include/asm/apb_timer.h:65:42: warning: ‘return’ with a value, in function returning void [enabled by default] drivers/watchdog/intel_scu_watchdog.c: In function ‘intel_scu_watchdog_init’: drivers/watchdog/intel_scu_watchdog.c:468:2: error: implicit declaration of function ‘sfi_get_mtmr’ [-Werror=implicit-function-declaration] drivers/watchdog/intel_scu_watchdog.c:468:32: warning: assignment makes pointer from integer without a cast [enabled by default] cc1: some warnings being treated as errors make[1]: *** [drivers/watchdog/intel_scu_watchdog.o] Error 1 make: *** [drivers/watchdog/intel_scu_watchdog.o] Error 2 Additionally, linux/types.h is needlessly being included twice in drivers/watchdog/intel_scu_watchdog.c Signed-off-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2011-06-27Fix node_start/end_pfn() definition for mm/page_cgroup.cKAMEZAWA Hiroyuki
commit 21a3c96 uses node_start/end_pfn(nid) for detection start/end of nodes. But, it's not defined in linux/mmzone.h but defined in /arch/???/include/mmzone.h which is included only under CONFIG_NEED_MULTIPLE_NODES=y. Then, we see mm/page_cgroup.c: In function 'page_cgroup_init': mm/page_cgroup.c:308: error: implicit declaration of function 'node_start_pfn' mm/page_cgroup.c:309: error: implicit declaration of function 'node_end_pfn' So, fixiing page_cgroup.c is an idea... But node_start_pfn()/node_end_pfn() is a very generic macro and should be implemented in the same manner for all archs. (m32r has different implementation...) This patch removes definitions of node_start/end_pfn() in each archs and defines a unified one in linux/mmzone.h. It's not under CONFIG_NEED_MULTIPLE_NODES, now. A result of macro expansion is here (mm/page_cgroup.c) for !NUMA start_pfn = ((&contig_page_data)->node_start_pfn); end_pfn = ({ pg_data_t *__pgdat = (&contig_page_data); __pgdat->node_start_pfn + __pgdat->node_spanned_pages;}); for NUMA (x86-64) start_pfn = ((node_data[nid])->node_start_pfn); end_pfn = ({ pg_data_t *__pgdat = (node_data[nid]); __pgdat->node_start_pfn + __pgdat->node_spanned_pages;}); Changelog: - fixed to avoid using "nid" twice in node_end_pfn() macro. Reported-and-acked-by: Randy Dunlap <randy.dunlap@oracle.com> Reported-and-tested-by: Ingo Molnar <mingo@elte.hu> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-20Merge branch 'kvm-updates/3.0' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
* 'kvm-updates/3.0' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: Fix register corruption in pvclock_scale_delta KVM: MMU: fix opposite condition in mapping_level_dirty_bitmap KVM: VMX: do not overwrite uptodate vcpu->arch.cr3 on KVM_SET_SREGS KVM: MMU: Fix build warnings in walk_addr_generic()
2011-06-19KVM: Fix register corruption in pvclock_scale_deltaZachary Amsden
The 128-bit multiply in pvclock.h was missing an output constraint for EDX which caused a register corruption to appear. Thanks to Ulrich for diagnosing the EDX corruption and Avi for providing this fix. Signed-off-by: Zachary Amsden <zamsden@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-06-18x86, efi: Do not reserve boot services regions within reserved areasMaarten Lankhorst
Commit 916f676f8dc started reserving boot service code since some systems require you to keep that code around until SetVirtualAddressMap is called. However, in some cases those areas will overlap with reserved regions. The proper medium-term fix is to fix the bootloader to prevent the conflicts from occurring by moving the kernel to a better position, but the kernel should check for this possibility, and only reserve regions which can be reserved. Signed-off-by: Maarten Lankhorst <m.b.lankhorst@gmail.com> Link: http://lkml.kernel.org/r/4DF7A005.1050407@gmail.com Acked-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-29Merge branch 'idle-release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6 * 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6: x86 idle: deprecate mwait_idle() and "idle=mwait" cmdline param x86 idle: deprecate "no-hlt" cmdline param x86 idle APM: deprecate CONFIG_APM_CPU_IDLE x86 idle floppy: deprecate disable_hlt() x86 idle: EXPORT_SYMBOL(default_idle, pm_idle) only when APM demands it x86 idle: clarify AMD erratum 400 workaround idle governor: Avoid lock acquisition to read pm_qos before entering idle cpuidle: menu: fixed wrapping timers at 4.294 seconds
2011-05-29x86 idle: clarify AMD erratum 400 workaroundLen Brown
The workaround for AMD erratum 400 uses the term "c1e" falsely suggesting: 1. Intel C1E is somehow involved 2. All AMD processors with C1E are involved Use the string "amd_c1e" instead of simply "c1e" to clarify that this workaround is specific to AMD's version of C1E. Use the string "e400" to clarify that the workaround is specific to AMD processors with Erratum 400. This patch is text-substitution only, with no functional change. cc: x86@kernel.org Acked-by: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: Len Brown <len.brown@intel.com>
2011-05-28Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, asm: Clean up desc.h a bit x86, amd: Do not enable ARAT feature on AMD processors below family 0x12 x86: Move do_page_fault()'s error path under unlikely() x86, efi: Retain boot service code until after switching to virtual mode x86: Remove unnecessary check in detect_ht() x86: Reorder mm_context_t to remove x86_64 alignment padding and thus shrink mm_struct x86, UV: Clean up uv_tlb.c x86, UV: Add support for SGI UV2 hub chip x86, cpufeature: Update CPU feature RDRND to RDRAND
2011-05-28Merge branch 'setns'Linus Torvalds
* setns: ns: Wire up the setns system call Done as a merge to make it easier to fix up conflicts in arm due to addition of sendmmsg system call
2011-05-28ns: Wire up the setns system callEric W. Biederman
32bit and 64bit on x86 are tested and working. The rest I have looked at closely and I can't find any problems. setns is an easy system call to wire up. It just takes two ints so I don't expect any weird architecture porting problems. While doing this I have noticed that we have some architectures that are very slow to get new system calls. cris seems to be the slowest where the last system calls wired up were preadv and pwritev. avr32 is weird in that recvmmsg was wired up but never declared in unistd.h. frv is behind with perf_event_open being the last syscall wired up. On h8300 the last system call wired up was epoll_wait. On m32r the last system call wired up was fallocate. mn10300 has recvmmsg as the last system call wired up. The rest seem to at least have syncfs wired up which was new in the 2.6.39. v2: Most of the architecture support added by Daniel Lezcano <dlezcano@fr.ibm.com> v3: ported to v2.6.36-rc4 by: Eric W. Biederman <ebiederm@xmission.com> v4: Moved wiring up of the system call to another patch v5: ported to v2.6.39-rc6 v6: rebased onto parisc-next and net-next to avoid syscall conflicts. v7: ported to Linus's latest post 2.6.39 tree. >  arch/blackfin/include/asm/unistd.h     |    3 ++- >  arch/blackfin/mach-common/entry.S      |    1 + Acked-by: Mike Frysinger <vapier@gentoo.org> Oh - ia64 wiring looks good. Acked-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-27Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: PM: Fix PM QOS's user mode interface to work with ASCII input PM / Hibernate: Update kerneldoc comments in hibernate.c PM / Hibernate: Remove arch_prepare_suspend() PM / Hibernate: Update some comments in core hibernate code
2011-05-27x86, asm: Clean up desc.h a bitIngo Molnar
I have looked at this file and found it rather ugly - improve readability a bit. No change in functionality. Link: http://lkml.kernel.org/n/tip-incpt6y26yd8586idx65t9ll@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-26kgdbts: unify/generalize gdb breakpoint adjustmentMike Frysinger
The Blackfin arch, like the x86 arch, needs to adjust the PC manually after a breakpoint is hit as normally this is handled by the remote gdb. However, rather than starting another arch ifdef mess, create a common GDB_ADJUSTS_BREAK_OFFSET define for any arch to opt-in via their kgdb.h. Signed-off-by: Mike Frysinger <vapier@gentoo.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Acked-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Dongdong Deng <dongdong.deng@windriver.com> Cc: Sergei Shtylyov <sshtylyov@mvista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26x86: convert to asm-generic ptrace.hMike Frysinger
Signed-off-by: Mike Frysinger <vapier@gentoo.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Sergei Shtylyov <sshtylyov@mvista.com> Cc: Dongdong Deng <dongdong.deng@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26Merge branch 'x86-vdso-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: vdso: Remove unused variable x86-64: Optimize vDSO time() x86-64: Add time to vDSO x86-64: Turn off -pg and turn on -foptimize-sibling-calls for vDSO x86-64: Move vread_tsc into a new file with sensible options x86-64: Vclock_gettime(CLOCK_MONOTONIC) can't ever see nsec < 0 x86-64: Don't generate cmov in vread_tsc x86-64: Remove unnecessary barrier in vread_tsc x86-64: Clean up vdso/kernel shared variables