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2013-07-14x86: delete __cpuinit usage from all x86 filesPaul Gortmaker
The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) are flagged as __cpuinit -- so if we remove the __cpuinit from arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the arch/x86 uses of the __cpuinit macros from all C files. x86 only had the one __CPUINIT used in assembly files, and it wasn't paired off with a .previous or a __FINIT, so we can delete it directly w/o any corresponding additional change there. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-06Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer core updates from Thomas Gleixner: "The timer changes contain: - posix timer code consolidation and fixes for odd corner cases - sched_clock implementation moved from ARM to core code to avoid duplication by other architectures - alarm timer updates - clocksource and clockevents unregistration facilities - clocksource/events support for new hardware - precise nanoseconds RTC readout (Xen feature) - generic support for Xen suspend/resume oddities - the usual lot of fixes and cleanups all over the place The parts which touch other areas (ARM/XEN) have been coordinated with the relevant maintainers. Though this results in an handful of trivial to solve merge conflicts, which we preferred over nasty cross tree merge dependencies. The patches which have been committed in the last few days are bug fixes plus the posix timer lot. The latter was in akpms queue and next for quite some time; they just got forgotten and Frederic collected them last minute." * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (59 commits) hrtimer: Remove unused variable hrtimers: Move SMP function call to thread context clocksource: Reselect clocksource when watchdog validated high-res capability posix-cpu-timers: don't account cpu timer after stopped thread runtime accounting posix_timers: fix racy timer delta caching on task exit posix-timers: correctly get dying task time sample in posix_cpu_timer_schedule() selftests: add basic posix timers selftests posix_cpu_timers: consolidate expired timers check posix_cpu_timers: consolidate timer list cleanups posix_cpu_timer: consolidate expiry time type tick: Sanitize broadcast control logic tick: Prevent uncontrolled switch to oneshot mode tick: Make oneshot broadcast robust vs. CPU offlining x86: xen: Sync the CMOS RTC as well as the Xen wallclock x86: xen: Sync the wallclock when the system time is set timekeeping: Indicate that clock was set in the pvclock gtod notifier timekeeping: Pass flags instead of multiple bools to timekeeping_update() xen: Remove clock_was_set() call in the resume path hrtimers: Support resuming with two or more CPUs online (but stopped) timer: Fix jiffies wrap behavior of round_jiffies_common() ...
2013-07-04Merge branch 'timers/posix-cpu-timers-for-tglx' ofThomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into timers/core Frederic sayed: "Most of these patches have been hanging around for several month now, in -mmotm for a significant chunk. They already missed a few releases." Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-07-03Merge tag 'stable/for-linus-3.11-rc0-tag-two' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen bugfixes from Konrad Rzeszutek Wilk: - Fix memory leak when CPU hotplugging. - Compile bugs with various #ifdefs - Fix state changes in Xen PCI front not dealing well with new toolstack. - Cleanups in code (use pr_*, fix 80 characters splits, etc) - Long standing bug in double-reporting the steal time * tag 'stable/for-linus-3.11-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/time: remove blocked time accounting from xen "clockchip" xen: Convert printks to pr_<level> xen: ifdef CONFIG_HIBERNATE_CALLBACKS xen_*_suspend xen/pcifront: Deal with toolstack missing 'XenbusStateClosing' state. xen/time: Free onlined per-cpu data structure if we want to online it again. xen/time: Check that the per_cpu data structure has data before freeing. xen/time: Don't leak interrupt name when offlining. xen/time: Encapsulate the struct clock_event_device in another structure. xen/spinlock: Don't leak interrupt name when offlining. xen/smp: Don't leak interrupt name when offlining. xen/smp: Set the per-cpu IRQ number to a valid default. xen/smp: Introduce a common structure to contain the IRQ name and interrupt line. xen/smp: Coalesce the free_irq calls in one function. xen-pciback: fix error return code in pcistub_irq_handler_switch()
2013-07-02Merge branch 'x86-fpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 FPU changes from Ingo Molnar: "There are two bigger changes in this tree: - Add an [early-use-]safe static_cpu_has() variant and other robustness improvements, including the new X86_DEBUG_STATIC_CPU_HAS configurable debugging facility, motivated by recent obscure FPU code bugs, by Borislav Petkov - Reimplement FPU detection code in C and drop the old asm code, by Peter Anvin." * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, fpu: Use static_cpu_has_safe before alternatives x86: Add a static_cpu_has_safe variant x86: Sanity-check static_cpu_has usage x86, cpu: Add a synthetic, always true, cpu feature x86: Get rid of ->hard_math and all the FPU asm fu
2013-06-28x86: xen: Sync the CMOS RTC as well as the Xen wallclockDavid Vrabel
Adjustments to Xen's persistent clock via update_persistent_clock() don't actually persist, as the Xen wallclock is a software only clock and modifications to it do not modify the underlying CMOS RTC. The x86_platform.set_wallclock hook is there to keep the hardware RTC synchronized. On a guest this is pointless. On Dom0 we can use the native implementaion which actually updates the hardware RTC, but we still need to keep the software emulation of RTC for the guests up to date. The subscription to the pvclock_notifier allows us to emulate this easily. The notifier is called at every tick and when the clock was set. Right now we only use that notifier when the clock was set, but due to the fact that it is called periodically from the timekeeping update code, we can utilize it to emulate the NTP driven drift compensation of update_persistant_clock() for the Xen wall (software) clock. Add a 11 minutes periodic update to the pvclock_gtod notifier callback to achieve that. The static variable 'next' which maintains that 11 minutes update cycle is protected by the core code serialization so there is no need to add a Xen specific serialization mechanism. [ tglx: Massaged changelog and added a few comments ] Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: John Stultz <john.stultz@linaro.org> Cc: <xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/1372329348-20841-6-git-send-email-david.vrabel@citrix.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-06-28x86: xen: Sync the wallclock when the system time is setDavid Vrabel
Currently the Xen wallclock is only updated every 11 minutes if NTP is synchronized to its clock source (using the sync_cmos_clock() work). If a guest is started before NTP is synchronized it may see an incorrect wallclock time. Use the pvclock_gtod notifier chain to receive a notification when the system time has changed and update the wallclock to match. This chain is called on every timer tick and we want to avoid an extra (expensive) hypercall on every tick. Because dom0 has historically never provided a very accurate wallclock and guests do not expect one, we can do this simply: the wallclock is only updated if the clock was set. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: John Stultz <john.stultz@linaro.org> Cc: <xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/1372329348-20841-5-git-send-email-david.vrabel@citrix.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-06-28xen/time: remove blocked time accounting from xen "clockchip"Laszlo Ersek
... because the "clock_event_device framework" already accounts for idle time through the "event_handler" function pointer in xen_timer_interrupt(). The patch is intended as the completion of [1]. It should fix the double idle times seen in PV guests' /proc/stat [2]. It should be orthogonal to stolen time accounting (the removed code seems to be isolated). The approach may be completely misguided. [1] https://lkml.org/lkml/2011/10/6/10 [2] http://lists.xensource.com/archives/html/xen-devel/2010-08/msg01068.html John took the time to retest this patch on top of v3.10 and reported: "idle time is correctly incremented for pv and hvm for the normal case, nohz=off and nohz=idle." so lets put this patch in. CC: stable@vger.kernel.org Signed-off-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: John Haxby <john.haxby@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10xen/time: Free onlined per-cpu data structure if we want to online it again.Konrad Rzeszutek Wilk
If the per-cpu time data structure has been onlined already and we are trying to online it again, then free the previous copy before blindly over-writting it. A developer naturally should not call this function multiple times but just in case. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10xen/time: Check that the per_cpu data structure has data before freeing.Konrad Rzeszutek Wilk
We don't check whether the per_cpu data structure has actually been freed in the past. This checks it and if it has been freed in the past then just continues on without double-freeing. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10xen/time: Don't leak interrupt name when offlining.Konrad Rzeszutek Wilk
When the user does: echo 0 > /sys/devices/system/cpu/cpu1/online echo 1 > /sys/devices/system/cpu/cpu1/online kmemleak reports: kmemleak: 7 new suspected memory leaks (see /sys/kernel/debug/kmemleak) One of the leaks is from xen/time: unreferenced object 0xffff88003fa51280 (size 32): comm "swapper/0", pid 1, jiffies 4294667339 (age 1027.789s) hex dump (first 32 bytes): 74 69 6d 65 72 31 00 00 00 00 00 00 00 00 00 00 timer1.......... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff81660721>] kmemleak_alloc+0x21/0x50 [<ffffffff81190aac>] __kmalloc_track_caller+0xec/0x2a0 [<ffffffff812fe1bb>] kvasprintf+0x5b/0x90 [<ffffffff812fe228>] kasprintf+0x38/0x40 [<ffffffff81041ec1>] xen_setup_timer+0x51/0xf0 [<ffffffff8166339f>] xen_cpu_up+0x5f/0x3e8 [<ffffffff8166bbf5>] _cpu_up+0xd1/0x14b [<ffffffff8166bd48>] cpu_up+0xd9/0xec [<ffffffff81ae6e4a>] smp_init+0x4b/0xa3 [<ffffffff81ac4981>] kernel_init_freeable+0xdb/0x1e6 [<ffffffff8165ce39>] kernel_init+0x9/0xf0 [<ffffffff8167edfc>] ret_from_fork+0x7c/0xb0 [<ffffffffffffffff>] 0xffffffffffffffff This patch fixes it by stashing away the 'name' in the per-cpu data structure and freeing it when offlining the CPU. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10xen/time: Encapsulate the struct clock_event_device in another structure.Konrad Rzeszutek Wilk
We don't do any code movement. We just encapsulate the struct clock_event_device in a new structure which contains said structure and a pointer to a char *name. The 'name' will be used in 'xen/time: Don't leak interrupt name when offlining'. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10xen/spinlock: Don't leak interrupt name when offlining.Konrad Rzeszutek Wilk
When the user does: echo 0 > /sys/devices/system/cpu/cpu1/online echo 1 > /sys/devices/system/cpu/cpu1/online kmemleak reports: kmemleak: 7 new suspected memory leaks (see /sys/kernel/debug/kmemleak) unreferenced object 0xffff88003fa51260 (size 32): comm "swapper/0", pid 1, jiffies 4294667339 (age 1027.789s) hex dump (first 32 bytes): 73 70 69 6e 6c 6f 63 6b 31 00 00 00 00 00 00 00 spinlock1....... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff81660721>] kmemleak_alloc+0x21/0x50 [<ffffffff81190aac>] __kmalloc_track_caller+0xec/0x2a0 [<ffffffff812fe1bb>] kvasprintf+0x5b/0x90 [<ffffffff812fe228>] kasprintf+0x38/0x40 [<ffffffff81663789>] xen_init_lock_cpu+0x61/0xbe [<ffffffff816633a6>] xen_cpu_up+0x66/0x3e8 [<ffffffff8166bbf5>] _cpu_up+0xd1/0x14b [<ffffffff8166bd48>] cpu_up+0xd9/0xec [<ffffffff81ae6e4a>] smp_init+0x4b/0xa3 [<ffffffff81ac4981>] kernel_init_freeable+0xdb/0x1e6 [<ffffffff8165ce39>] kernel_init+0x9/0xf0 [<ffffffff8167edfc>] ret_from_fork+0x7c/0xb0 [<ffffffffffffffff>] 0xffffffffffffffff Instead of doing it like the "xen/smp: Don't leak interrupt name when offlining" patch did (which has a per-cpu structure which contains both the IRQ number and char*) we use a per-cpu pointers to a *char. The reason is that the "__this_cpu_read(lock_kicker_irq);" macro blows up with "__bad_size_call_parameter()" as the size of the returned structure is not within the parameters of what it expects and optimizes for. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10xen/smp: Don't leak interrupt name when offlining.Konrad Rzeszutek Wilk
When the user does: echo 0 > /sys/devices/system/cpu/cpu1/online echo 1 > /sys/devices/system/cpu/cpu1/online kmemleak reports: kmemleak: 7 new suspected memory leaks (see /sys/kernel/debug/kmemleak) unreferenced object 0xffff88003fa51240 (size 32): comm "swapper/0", pid 1, jiffies 4294667339 (age 1027.789s) hex dump (first 32 bytes): 72 65 73 63 68 65 64 31 00 00 00 00 00 00 00 00 resched1........ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff81660721>] kmemleak_alloc+0x21/0x50 [<ffffffff81190aac>] __kmalloc_track_caller+0xec/0x2a0 [<ffffffff812fe1bb>] kvasprintf+0x5b/0x90 [<ffffffff812fe228>] kasprintf+0x38/0x40 [<ffffffff81047ed1>] xen_smp_intr_init+0x41/0x2c0 [<ffffffff816636d3>] xen_cpu_up+0x393/0x3e8 [<ffffffff8166bbf5>] _cpu_up+0xd1/0x14b [<ffffffff8166bd48>] cpu_up+0xd9/0xec [<ffffffff81ae6e4a>] smp_init+0x4b/0xa3 [<ffffffff81ac4981>] kernel_init_freeable+0xdb/0x1e6 [<ffffffff8165ce39>] kernel_init+0x9/0xf0 [<ffffffff8167edfc>] ret_from_fork+0x7c/0xb0 [<ffffffffffffffff>] 0xffffffffffffffff This patch fixes some of it by using the 'struct xen_common_irq->name' field to stash away the char so that it can be freed when the interrupt line is destroyed. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10xen/smp: Set the per-cpu IRQ number to a valid default.Konrad Rzeszutek Wilk
When we free it we want to make sure to set it to a default value of -1 so that we don't double-free it (in case somebody calls us twice). Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10xen/smp: Introduce a common structure to contain the IRQ name and interrupt ↵Konrad Rzeszutek Wilk
line. This patch adds a new structure to contain the common two things that each of the per-cpu interrupts need: - an interrupt number, - and the name of the interrupt (to be added in 'xen/smp: Don't leak interrupt name when offlining'). This allows us to carry the tuple of the per-cpu interrupt data structure and expand it as we need in the future. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10xen/smp: Coalesce the free_irq calls in one function.Konrad Rzeszutek Wilk
There are two functions that do a bunch of 'free_irq' on the per_cpu IRQ. Instead of having duplicate code just move it to one function. This is just code movement. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-06x86: Get rid of ->hard_math and all the FPU asm fuH. Peter Anvin
Reimplement FPU detection code in C and drop old, not-so-recommended detection method in asm. Move all the relevant stuff into i387.c where it conceptually belongs. Finally drop cpuinfo_x86.hard_math. [ hpa: huge thanks to Borislav for taking my original concept patch and productizing it ] [ Boris, note to self: do not use static_cpu_has before alternatives! ] Signed-off-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1367244262-29511-2-git-send-email-bp@alien8.de Link: http://lkml.kernel.org/r/1365436666-9837-2-git-send-email-bp@alien8.de Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-06-04xen/smp: Fixup NOHZ per cpu data when onlining an offline CPU.Konrad Rzeszutek Wilk
The xen_play_dead is an undead function. When the vCPU is told to offline it ends up calling xen_play_dead wherin it calls the VCPUOP_down hypercall which offlines the vCPU. However, when the vCPU is onlined back, it resumes execution right after VCPUOP_down hypercall. That was OK (albeit the API for play_dead assumes that the CPU stays dead and never returns) but with commit 4b0c0f294 (tick: Cleanup NOHZ per cpu data on cpu down) that is no longer safe as said commit resets the ts->inidle which at the start of the cpu_idle loop was set. The net effect is that we get this warn: Broke affinity for irq 16 installing Xen timer for CPU 1 cpu 1 spinlock event irq 48 ------------[ cut here ]------------ WARNING: at /home/konrad/linux-linus/kernel/time/tick-sched.c:935 tick_nohz_idle_exit+0x195/0x1b0() Modules linked in: dm_multipath dm_mod xen_evtchn iscsi_boot_sysfs CPU: 1 PID: 0 Comm: swapper/1 Not tainted 3.10.0-rc3upstream-00068-gdcdbe33 #1 Hardware name: BIOSTAR Group N61PB-M2S/N61PB-M2S, BIOS 6.00 PG 09/03/2009 ffffffff8193b448 ffff880039da5e60 ffffffff816707c8 ffff880039da5ea0 ffffffff8108ce8b ffff880039da4010 ffff88003fa8e500 ffff880039da4010 0000000000000001 ffff880039da4000 ffff880039da4010 ffff880039da5eb0 Call Trace: [<ffffffff816707c8>] dump_stack+0x19/0x1b [<ffffffff8108ce8b>] warn_slowpath_common+0x6b/0xa0 [<ffffffff8108ced5>] warn_slowpath_null+0x15/0x20 [<ffffffff810e4745>] tick_nohz_idle_exit+0x195/0x1b0 [<ffffffff810da755>] cpu_startup_entry+0x205/0x250 [<ffffffff81661070>] cpu_bringup_and_idle+0x13/0x15 ---[ end trace 915c8c486004dda1 ]--- b/c ts_inidle is set to zero. Thomas suggested that we just add a workaround to call tick_nohz_idle_enter before returning from xen_play_dead() - and that is what this patch does and fixes the issue. We also add the stable part b/c git commit 4b0c0f294 is on the stable tree. CC: stable@vger.kernel.org Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-29xen: Clean up apic ipi interfaceStefan Bader
Commit f447d56d36af18c5104ff29dcb1327c0c0ac3634 introduced the implementation of the PV apic ipi interface. But there were some odd things (it seems none of which cause really any issue but maybe they should be cleaned up anyway): - xen_send_IPI_mask_allbutself (and by that xen_send_IPI_allbutself) ignore the passed in vector and only use the CALL_FUNCTION_SINGLE vector. While xen_send_IPI_all and xen_send_IPI_mask use the vector. - physflat_send_IPI_allbutself is declared unnecessarily. It is never used. This patch tries to clean up those things. Signed-off-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-28x86: Increase precision of x86_platform.get/set_wallclock()David Vrabel
All the virtualized platforms (KVM, lguest and Xen) have persistent wallclocks that have more than one second of precision. read_persistent_wallclock() and update_persistent_wallclock() allow for nanosecond precision but their implementation on x86 with x86_platform.get/set_wallclock() only allows for one second precision. This means guests may see a wallclock time that is off by up to 1 second. Make set_wallclock() and get_wallclock() take a struct timespec parameter (which allows for nanosecond precision) so KVM and Xen guests may start with a more accurate wallclock time and a Xen dom0 can maintain a more accurate wallclock for guests. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-05-11Merge tag 'stable/for-linus-3.10-rc0-tag-two' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen bug-fixes from Konrad Rzeszutek Wilk: - More fixes in the vCPU PVHVM hotplug path. - Add more documentation. - Fix various ARM related issues in the Xen generic drivers. - Updates in the xen-pciback driver per Bjorn's updates. - Mask the x2APIC feature for PV guests. * tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/pci: Used cached MSI-X capability offset xen/pci: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASK xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST xen: mask x2APIC feature in PV xen: SWIOTLB is only used on x86 xen/spinlock: Fix check from greater than to be also be greater or equal to. xen/smp/pvhvm: Don't point per_cpu(xen_vpcu, 33 and larger) to shared_info xen/vcpu: Document the xen_vcpu_info and xen_vcpu xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.
2013-05-08xen: mask x2APIC feature in PVZhenzhong Duan
On x2apic enabled pvm, doing sysrq+l, got NULL pointer dereference as below. SysRq : Show backtrace of all active CPUs BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8125e3cb>] memcpy+0xb/0x120 Call Trace: [<ffffffff81039633>] ? __x2apic_send_IPI_mask+0x73/0x160 [<ffffffff8103973e>] x2apic_send_IPI_all+0x1e/0x20 [<ffffffff8103498c>] arch_trigger_all_cpu_backtrace+0x6c/0xb0 [<ffffffff81501be4>] ? _raw_spin_lock_irqsave+0x34/0x50 [<ffffffff8131654e>] sysrq_handle_showallcpus+0xe/0x10 [<ffffffff8131616d>] __handle_sysrq+0x7d/0x140 [<ffffffff81316230>] ? __handle_sysrq+0x140/0x140 [<ffffffff81316287>] write_sysrq_trigger+0x57/0x60 [<ffffffff811ca996>] proc_reg_write+0x86/0xc0 [<ffffffff8116dd8e>] vfs_write+0xce/0x190 [<ffffffff8116e3e5>] sys_write+0x55/0x90 [<ffffffff8150a242>] system_call_fastpath+0x16/0x1b That's because apic points to apic_x2apic_cluster or apic_x2apic_phys but the basic element like cpumask isn't initialized. Mask x2APIC feature in pvm to avoid overwrite of apic pointer, update commit message per Konrad's suggestion. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Tested-by: Tamon Shiose <tamon.shiose@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-08xen/spinlock: Fix check from greater than to be also be greater or equal to.Konrad Rzeszutek Wilk
During review of git commit cb9c6f15f318aa3aeb62fe525aa5c6dcf6eee159 ("xen/spinlock: Check against default value of -1 for IRQ line.") Stefano pointed out a bug in the patch. Unfortunatly due to vacation timing the fix was not applied and this patch fixes it up. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-08xen/smp/pvhvm: Don't point per_cpu(xen_vpcu, 33 and larger) to shared_infoKonrad Rzeszutek Wilk
As it will point to some data, but not event channel data (the shared_info has an array limited to 32). This means that for PVHVM guests with more than 32 VCPUs without the usage of VCPUOP_register_info any interrupts to VCPUs larger than 32 would have gone unnoticed during early bootup. That is OK, as during early bootup, in smp_init we end up calling the hotplug mechanism (xen_hvm_cpu_notify) which makes the VCPUOP_register_vcpu_info call for all VCPUs and we can receive interrupts on VCPUs 33 and further. This is just a cleanup. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-07xen/vcpu: Document the xen_vcpu_info and xen_vcpuKonrad Rzeszutek Wilk
They are important structures and it is not clear at first look what they are for. The xen_vcpu is a pointer. By default it points to the shared_info structure (at the CPU offset location). However if the VCPUOP_register_vcpu_info hypercall is implemented we can make the xen_vcpu pointer point to a per-CPU location. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> [v1: Added comments from Ian Campbell] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-06xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.Konrad Rzeszutek Wilk
If a user did: echo 0 > /sys/devices/system/cpu/cpu1/online echo 1 > /sys/devices/system/cpu/cpu1/online we would (this a build with DEBUG enabled) get to: smpboot: ++++++++++++++++++++=_---CPU UP 1 .. snip.. smpboot: Stack at about ffff880074c0ff44 smpboot: CPU1: has booted. and hang. The RCU mechanism would kick in an try to IPI the CPU1 but the IPIs (and all other interrupts) would never arrive at the CPU1. At first glance at least. A bit digging in the hypervisor trace shows that (using xenanalyze): [vla] d4v1 vec 243 injecting 0.043163027 --|x d4v1 intr_window vec 243 src 5(vector) intr f3 ] 0.043163639 --|x d4v1 vmentry cycles 1468 ] 0.043164913 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254 0.043164913 --|x d4v1 inj_virq vec 243 real [vla] d4v1 vec 243 injecting 0.043164913 --|x d4v1 intr_window vec 243 src 5(vector) intr f3 ] 0.043165526 --|x d4v1 vmentry cycles 1472 ] 0.043166800 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254 0.043166800 --|x d4v1 inj_virq vec 243 real [vla] d4v1 vec 243 injecting there is a pending event (subsequent debugging shows it is the IPI from the VCPU0 when smpboot.c on VCPU1 has done "set_cpu_online(smp_processor_id(), true)") and the guest VCPU1 is interrupted with the callback IPI (0xf3 aka 243) which ends up calling __xen_evtchn_do_upcall. The __xen_evtchn_do_upcall seems to do *something* but not acknowledge the pending events. And the moment the guest does a 'cli' (that is the ffffffff81673254 in the log above) the hypervisor is invoked again to inject the IPI (0xf3) to tell the guest it has pending interrupts. This repeats itself forever. The culprit was the per_cpu(xen_vcpu, cpu) pointer. At the bootup we set each per_cpu(xen_vcpu, cpu) to point to the shared_info->vcpu_info[vcpu] but later on use the VCPUOP_register_vcpu_info to register per-CPU structures (xen_vcpu_setup). This is used to allow events for more than 32 VCPUs and for performance optimizations reasons. When the user performs the VCPU hotplug we end up calling the the xen_vcpu_setup once more. We make the hypercall which returns -EINVAL as it does not allow multiple registration calls (and already has re-assigned where the events are being set). We pick the fallback case and set per_cpu(xen_vcpu, cpu) to point to the shared_info->vcpu_info[vcpu] (which is a good fallback during bootup). However the hypervisor is still setting events in the register per-cpu structure (per_cpu(xen_vcpu_info, cpu)). As such when the events are set by the hypervisor (such as timer one), and when we iterate in __xen_evtchn_do_upcall we end up reading stale events from the shared_info->vcpu_info[vcpu] instead of the per_cpu(xen_vcpu_info, cpu) structures. Hence we never acknowledge the events that the hypervisor has set and the hypervisor keeps on reminding us to ack the events which we never do. The fix is simple. Don't on the second time when xen_vcpu_setup is called over-write the per_cpu(xen_vcpu, cpu) if it points to per_cpu(xen_vcpu_info). Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> CC: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-30Merge branch 'x86-paravirt-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 paravirt update from Ingo Molnar: "Various paravirtualization related changes - the biggest one makes guest support optional via CONFIG_HYPERVISOR_GUEST" * 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, wakeup, sleep: Use pvops functions for changing GDT entries x86, xen, gdt: Remove the pvops variant of store_gdt. x86-32, gdt: Store/load GDT for ACPI S3 or hibernation/resume path is not needed x86-64, gdt: Store/load GDT for ACPI S3 or hibernate/resume path is not needed. x86: Make Linux guest support optional x86, Kconfig: Move PARAVIRT_DEBUG into the paravirt menu
2013-04-30Merge branch 'x86-kaslr-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perparatory x86 kasrl changes from Ingo Molnar: "This contains changes from the ongoing KASLR work, by Kees Cook. The main changes are the use of a read-only IDT on x86 (which decouples the userspace visible virtual IDT address from the physical address), and a rework of ELF relocation support, in preparation of random, boot-time kernel image relocation." * 'x86-kaslr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, relocs: Refactor the relocs tool to merge 32- and 64-bit ELF x86, relocs: Build separate 32/64-bit tools x86, relocs: Add 64-bit ELF support to relocs tool x86, relocs: Consolidate processing logic x86, relocs: Generalize ELF structure names x86: Use a read-only IDT alias on all CPUs
2013-04-30Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull SMP/hotplug changes from Ingo Molnar: "This is a pretty large, multi-arch series unifying and generalizing the various disjunct pieces of idle routines that architectures have historically copied from each other and have grown in random, wildly inconsistent and sometimes buggy directions: 101 files changed, 455 insertions(+), 1328 deletions(-) this went through a number of review and test iterations before it was committed, it was tested on various architectures, was exposed to linux-next for quite some time - nevertheless it might cause problems on architectures that don't read the mailing lists and don't regularly test linux-next. This cat herding excercise was motivated by the -rt kernel, and was brought to you by Thomas "the Whip" Gleixner." * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) idle: Remove GENERIC_IDLE_LOOP config switch um: Use generic idle loop ia64: Make sure interrupts enabled when we "safe_halt()" sparc: Use generic idle loop idle: Remove unused ARCH_HAS_DEFAULT_IDLE bfin: Fix typo in arch_cpu_idle() xtensa: Use generic idle loop x86: Use generic idle loop unicore: Use generic idle loop tile: Use generic idle loop tile: Enter idle with preemption disabled sh: Use generic idle loop score: Use generic idle loop s390: Use generic idle loop powerpc: Use generic idle loop parisc: Use generic idle loop openrisc: Use generic idle loop mn10300: Use generic idle loop mips: Use generic idle loop microblaze: Use generic idle loop ...
2013-04-29Merge tag 'stable/for-linus-3.10-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen updates from Konrad Rzeszutek Wilk: "Features: - Populate the boot_params with EDD data. - Cleanups in the IRQ code. Bug-fixes: - CPU hotplug offline/online in PVHVM mode. - Re-upload processor PM data after ACPI S3 suspend/resume cycle." And Konrad gets a gold star for sending the pull request early when he thought he'd be away for the first week of the merge window (but because of 3.9 dragging out to -rc8 he then re-sent the reminder on the first day of the merge window anyway) * tag 'stable/for-linus-3.10-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: resolve section mismatch warnings in xen-acpi-processor xen: Re-upload processor PM data to hypervisor after S3 resume (v2) xen/smp: Unifiy some of the PVs and PVHVM offline CPU path xen/smp/pvhvm: Don't initialize IRQ_WORKER as we are using the native one. xen/spinlock: Disable IRQ spinlock (PV) allocation on PVHVM xen/spinlock: Check against default value of -1 for IRQ line. xen/time: Add default value of -1 for IRQ and check for that. xen/events: Check that IRQ value passed in is valid. xen/time: Fix kasprintf splat when allocating timer%d IRQ line. xen/smp/spinlock: Fix leakage of the spinlock interrupt line for every CPU online/offline xen/smp: Fix leakage of timer interrupt line for every CPU online/offline. xen kconfig: fix select INPUT_XEN_KBDDEV_FRONTEND xen: drop tracking of IRQ vector x86/xen: populate boot_params with EDD data
2013-04-16xen/smp: Unifiy some of the PVs and PVHVM offline CPU pathKonrad Rzeszutek Wilk
The "xen_cpu_die" and "xen_hvm_cpu_die" are very similar. Lets coalesce them. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-16xen/smp/pvhvm: Don't initialize IRQ_WORKER as we are using the native one.Konrad Rzeszutek Wilk
There is no need to use the PV version of the IRQ_WORKER mechanism as under PVHVM we are using the native version. The native version is using the SMP API. They just sit around unused: 69: 0 0 xen-percpu-ipi irqwork0 83: 0 0 xen-percpu-ipi irqwork1 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-16xen/spinlock: Disable IRQ spinlock (PV) allocation on PVHVMKonrad Rzeszutek Wilk
See git commit f10cd522c5fbfec9ae3cc01967868c9c2401ed23 (xen: disable PV spinlocks on HVM) for details. But we did not disable it everywhere - which means that when we boot as PVHVM we end up allocating per-CPU irq line for spinlock. This fixes that. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-16xen/spinlock: Check against default value of -1 for IRQ line.Konrad Rzeszutek Wilk
The default (uninitialized) value of the IRQ line is -1. Check if we already have allocated an spinlock interrupt line and if somebody is trying to do it again. Also set it to -1 when we offline the CPU. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-16xen/time: Add default value of -1 for IRQ and check for that.Konrad Rzeszutek Wilk
If the timer interrupt has been de-init or is just now being initialized, the default value of -1 should be preset as interrupt line. Check for that and if something is odd WARN us. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-16xen/time: Fix kasprintf splat when allocating timer%d IRQ line.Konrad Rzeszutek Wilk
When we online the CPU, we get this splat: smpboot: Booting Node 0 Processor 1 APIC 0x2 installing Xen timer for CPU 1 BUG: sleeping function called from invalid context at /home/konrad/ssd/konrad/linux/mm/slab.c:3179 in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper/1 Pid: 0, comm: swapper/1 Not tainted 3.9.0-rc6upstream-00001-g3884fad #1 Call Trace: [<ffffffff810c1fea>] __might_sleep+0xda/0x100 [<ffffffff81194617>] __kmalloc_track_caller+0x1e7/0x2c0 [<ffffffff81303758>] ? kasprintf+0x38/0x40 [<ffffffff813036eb>] kvasprintf+0x5b/0x90 [<ffffffff81303758>] kasprintf+0x38/0x40 [<ffffffff81044510>] xen_setup_timer+0x30/0xb0 [<ffffffff810445af>] xen_hvm_setup_cpu_clockevents+0x1f/0x30 [<ffffffff81666d0a>] start_secondary+0x19c/0x1a8 The solution to that is use kasprintf in the CPU hotplug path that 'online's the CPU. That is, do it in in xen_hvm_cpu_notify, and remove the call to in xen_hvm_setup_cpu_clockevents. Unfortunatly the later is not a good idea as the bootup path does not use xen_hvm_cpu_notify so we would end up never allocating timer%d interrupt lines when booting. As such add the check for atomic() to continue. CC: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-16xen/smp/spinlock: Fix leakage of the spinlock interrupt line for every CPU ↵Konrad Rzeszutek Wilk
online/offline While we don't use the spinlock interrupt line (see for details commit f10cd522c5fbfec9ae3cc01967868c9c2401ed23 - xen: disable PV spinlocks on HVM) - we should still do the proper init / deinit sequence. We did not do that correctly and for the CPU init for PVHVM guest we would allocate an interrupt line - but failed to deallocate the old interrupt line. This resulted in leakage of an irq_desc but more importantly this splat as we online an offlined CPU: genirq: Flags mismatch irq 71. 0002cc20 (spinlock1) vs. 0002cc20 (spinlock1) Pid: 2542, comm: init.late Not tainted 3.9.0-rc6upstream #1 Call Trace: [<ffffffff811156de>] __setup_irq+0x23e/0x4a0 [<ffffffff81194191>] ? kmem_cache_alloc_trace+0x221/0x250 [<ffffffff811161bb>] request_threaded_irq+0xfb/0x160 [<ffffffff8104c6f0>] ? xen_spin_trylock+0x20/0x20 [<ffffffff813a8423>] bind_ipi_to_irqhandler+0xa3/0x160 [<ffffffff81303758>] ? kasprintf+0x38/0x40 [<ffffffff8104c6f0>] ? xen_spin_trylock+0x20/0x20 [<ffffffff810cad35>] ? update_max_interval+0x15/0x40 [<ffffffff816605db>] xen_init_lock_cpu+0x3c/0x78 [<ffffffff81660029>] xen_hvm_cpu_notify+0x29/0x33 [<ffffffff81676bdd>] notifier_call_chain+0x4d/0x70 [<ffffffff810bb2a9>] __raw_notifier_call_chain+0x9/0x10 [<ffffffff8109402b>] __cpu_notify+0x1b/0x30 [<ffffffff8166834a>] _cpu_up+0xa0/0x14b [<ffffffff816684ce>] cpu_up+0xd9/0xec [<ffffffff8165f754>] store_online+0x94/0xd0 [<ffffffff8141d15b>] dev_attr_store+0x1b/0x20 [<ffffffff81218f44>] sysfs_write_file+0xf4/0x170 [<ffffffff811a2864>] vfs_write+0xb4/0x130 [<ffffffff811a302a>] sys_write+0x5a/0xa0 [<ffffffff8167ada9>] system_call_fastpath+0x16/0x1b cpu 1 spinlock event irq -16 smpboot: Booting Node 0 Processor 1 APIC 0x2 And if one looks at the /proc/interrupts right after offlining (CPU1): 70: 0 0 xen-percpu-ipi spinlock0 71: 0 0 xen-percpu-ipi spinlock1 77: 0 0 xen-percpu-ipi spinlock2 There is the oddity of the 'spinlock1' still being present. CC: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-16xen/smp: Fix leakage of timer interrupt line for every CPU online/offline.Konrad Rzeszutek Wilk
In the PVHVM path when we do CPU online/offline path we would leak the timer%d IRQ line everytime we do a offline event. The online path (xen_hvm_setup_cpu_clockevents via x86_cpuinit.setup_percpu_clockev) would allocate a new interrupt line for the timer%d. But we would still use the old interrupt line leading to: kernel BUG at /home/konrad/ssd/konrad/linux/kernel/hrtimer.c:1261! invalid opcode: 0000 [#1] SMP RIP: 0010:[<ffffffff810b9e21>] [<ffffffff810b9e21>] hrtimer_interrupt+0x261/0x270 .. snip.. <IRQ> [<ffffffff810445ef>] xen_timer_interrupt+0x2f/0x1b0 [<ffffffff81104825>] ? stop_machine_cpu_stop+0xb5/0xf0 [<ffffffff8111434c>] handle_irq_event_percpu+0x7c/0x240 [<ffffffff811175b9>] handle_percpu_irq+0x49/0x70 [<ffffffff813a74a3>] __xen_evtchn_do_upcall+0x1c3/0x2f0 [<ffffffff813a760a>] xen_evtchn_do_upcall+0x2a/0x40 [<ffffffff8167c26d>] xen_hvm_callback_vector+0x6d/0x80 <EOI> [<ffffffff81666d01>] ? start_secondary+0x193/0x1a8 [<ffffffff81666cfd>] ? start_secondary+0x18f/0x1a8 There is also the oddity (timer1) in the /proc/interrupts after offlining CPU1: 64: 1121 0 xen-percpu-virq timer0 78: 0 0 xen-percpu-virq timer1 84: 0 2483 xen-percpu-virq timer2 This patch fixes it. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: stable@vger.kernel.org
2013-04-16x86/xen: populate boot_params with EDD dataDavid Vrabel
During early setup of a dom0 kernel, populate boot_params with the Enhanced Disk Drive (EDD) and MBR signature data. This makes information on the BIOS boot device available in /sys/firmware/edd/. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-14Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Flush lazy MMU when DEBUG_PAGEALLOC is set x86/mm/cpa/selftest: Fix false positive in CPA self test x86/mm/cpa: Convert noop to functional fix x86, mm: Patch out arch_flush_lazy_mmu_mode() when running on bare metal x86, mm, paravirt: Fix vmalloc_fault oops during lazy MMU updates
2013-04-11x86, xen, gdt: Remove the pvops variant of store_gdt.Konrad Rzeszutek Wilk
The two use-cases where we needed to store the GDT were during ACPI S3 suspend and resume. As the patches: x86/gdt/i386: store/load GDT for ACPI S3 or hibernation/resume path is not needed x86/gdt/64-bit: store/load GDT for ACPI S3 or hibernate/resume path is not needed. have demonstrated - there are other mechanism by which the GDT is saved and reloaded during early resume path. Hence we do not need to worry about the pvops call-chain for saving the GDT and can and can eliminate it. The other areas where the store_gdt is used are never going to be hit when running under the pvops platforms. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Link: http://lkml.kernel.org/r/1365194544-14648-4-git-send-email-konrad.wilk@oracle.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-11x86: Use a read-only IDT alias on all CPUsKees Cook
Make a copy of the IDT (as seen via the "sidt" instruction) read-only. This primarily removes the IDT from being a target for arbitrary memory write attacks, and has the added benefit of also not leaking the kernel base offset, if it has been relocated. We already did this on vendor == Intel and family == 5 because of the F0 0F bug -- regardless of if a particular CPU had the F0 0F bug or not. Since the workaround was so cheap, there simply was no reason to be very specific. This patch extends the readonly alias to all CPUs, but does not activate the #PF to #UD conversion code needed to deliver the proper exception in the F0 0F case except on Intel family 5 processors. Signed-off-by: Kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/20130410192422.GA17344@www.outflux.net Cc: Eric Northup <digitaleric@google.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-10x86, mm: Patch out arch_flush_lazy_mmu_mode() when running on bare metalBoris Ostrovsky
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> Cc: <stable@vger.kernel.org> SEE NOTE ABOVE
2013-04-08x86: Use generic idle loopThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Magnus Damm <magnus.damm@gmail.com> Link: http://lkml.kernel.org/r/20130321215235.486594473@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org
2013-04-02xen/mmu: On early bootup, flush the TLB when changing RO->RW bits Xen ↵Konrad Rzeszutek Wilk
provided pagetables. Occassionaly on a DL380 G4 the guest would crash quite early with this: (XEN) d244:v0: unhandled page fault (ec=0003) (XEN) Pagetable walk from ffffffff84dc7000: (XEN) L4[0x1ff] = 00000000c3f18067 0000000000001789 (XEN) L3[0x1fe] = 00000000c3f14067 000000000000178d (XEN) L2[0x026] = 00000000dc8b2067 0000000000004def (XEN) L1[0x1c7] = 00100000dc8da067 0000000000004dc7 (XEN) domain_crash_sync called from entry.S (XEN) Domain 244 (vcpu#0) crashed on cpu#3: (XEN) ----[ Xen-4.1.3OVM x86_64 debug=n Not tainted ]---- (XEN) CPU: 3 (XEN) RIP: e033:[<ffffffff81263f22>] (XEN) RFLAGS: 0000000000000216 EM: 1 CONTEXT: pv guest (XEN) rax: 0000000000000000 rbx: ffffffff81785f88 rcx: 000000000000003f (XEN) rdx: 0000000000000000 rsi: 00000000dc8da063 rdi: ffffffff84dc7000 The offending code shows it to be a loop writting the value zero (%rax) in the %rdi (the L4 provided by Xen) register: 0: 44 00 00 add %r8b,(%rax) 3: 31 c0 xor %eax,%eax 5: b9 40 00 00 00 mov $0x40,%ecx a: 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1) 11: 00 00 13: ff c9 dec %ecx 15:* 48 89 07 mov %rax,(%rdi) <-- trapping instruction 18: 48 89 47 08 mov %rax,0x8(%rdi) 1c: 48 89 47 10 mov %rax,0x10(%rdi) which fails. xen_setup_kernel_pagetable recycles some of the Xen's page-table entries when it has switched over to its Linux page-tables. Right before try to clear the page, we make a hypercall to change it from _RO to _RW and that works (otherwise we would hit an BUG()). And the _RW flag is set for that page: (XEN) L1[0x1c7] = 001000004885f067 0000000000004dc7 The error code is 3, so PFEC_page_present and PFEC_write_access, so page is present (correct), and we tried to write to the page, but a violation occurred. The one theory is that the the page entries in hardware (which are cached) are not up to date with what we just set. Especially as we have just done an CR3 write and flushed the multicalls. This patch does solve the problem by flusing out the TLB page entry after changing it from _RO to _RW and we don't hit this issue anymore. Fixed-Oracle-Bug: 16243091 [ON OCCASIONS VM START GOES INTO 'CRASH' STATE: CLEAR_PAGE+0X12 ON HP DL380 G4] Reported-and-Tested-by: Saar Maoz <Saar.Maoz@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-27xen/mmu: Move the setting of pvops.write_cr3 to later phase in bootup.Konrad Rzeszutek Wilk
We move the setting of write_cr3 from the early bootup variant (see git commit 0cc9129d75ef8993702d97ab0e49542c15ac6ab9 "x86-64, xen, mmu: Provide an early version of write_cr3.") to a more appropiate location. This new location sets all of the other non-early variants of pvops calls - and most importantly is before the alternative_asm mechanism kicks in. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-04x86: Make Linux guest support optionalBorislav Petkov
Put all config options needed to run Linux as a guest behind a CONFIG_HYPERVISOR_GUEST menu so that they don't get built-in by default but be selectable by the user. Also, make all units which depend on x86_hyper, depend on this new symbol so that compilation doesn't fail when CONFIG_HYPERVISOR_GUEST is disabled but those units assume its presence. Sort options in the new HYPERVISOR_GUEST menu, adapt config text and drop redundant select. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1362428421-9244-3-git-send-email-bp@alien8.de Cc: Dmitry Torokhov <dtor@vmware.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-02-28xen/pat: Disable PAT using pat_enabled value.Konrad Rzeszutek Wilk
The git commit 8eaffa67b43e99ae581622c5133e20b0f48bcef1 (xen/pat: Disable PAT support for now) explains in details why we want to disable PAT for right now. However that change was not enough and we should have also disabled the pat_enabled value. Otherwise we end up with: mmap-example:3481 map pfn expected mapping type write-back for [mem 0x00010000-0x00010fff], got uncached-minus ------------[ cut here ]------------ WARNING: at /build/buildd/linux-3.8.0/arch/x86/mm/pat.c:774 untrack_pfn+0xb8/0xd0() mem 0x00010000-0x00010fff], got uncached-minus ------------[ cut here ]------------ WARNING: at /build/buildd/linux-3.8.0/arch/x86/mm/pat.c:774 untrack_pfn+0xb8/0xd0() ... Pid: 3481, comm: mmap-example Tainted: GF 3.8.0-6-generic #13-Ubuntu Call Trace: [<ffffffff8105879f>] warn_slowpath_common+0x7f/0xc0 [<ffffffff810587fa>] warn_slowpath_null+0x1a/0x20 [<ffffffff8104bcc8>] untrack_pfn+0xb8/0xd0 [<ffffffff81156c1c>] unmap_single_vma+0xac/0x100 [<ffffffff81157459>] unmap_vmas+0x49/0x90 [<ffffffff8115f808>] exit_mmap+0x98/0x170 [<ffffffff810559a4>] mmput+0x64/0x100 [<ffffffff810560f5>] dup_mm+0x445/0x660 [<ffffffff81056d9f>] copy_process.part.22+0xa5f/0x1510 [<ffffffff81057931>] do_fork+0x91/0x350 [<ffffffff81057c76>] sys_clone+0x16/0x20 [<ffffffff816ccbf9>] stub_clone+0x69/0x90 [<ffffffff816cc89d>] ? system_call_fastpath+0x1a/0x1f ---[ end trace 4918cdd0a4c9fea4 ]--- (a similar message shows up if you end up launching 'mcelog') The call chain is (as analyzed by Liu, Jinsong): do_fork --> copy_process --> dup_mm --> dup_mmap --> copy_page_range --> track_pfn_copy --> reserve_pfn_range --> line 624: flags != want_flags It comes from different memory types of page table (_PAGE_CACHE_WB) and MTRR (_PAGE_CACHE_UC_MINUS). Stefan Bader dug in this deep and found out that: "That makes it clearer as this will do reserve_memtype(...) --> pat_x_mtrr_type --> mtrr_type_lookup --> __mtrr_type_lookup And that can return -1/0xff in case of MTRR not being enabled/initialized. Which is not the case (given there are no messages for it in dmesg). This is not equal to MTRR_TYPE_WRBACK and thus becomes _PAGE_CACHE_UC_MINUS. It looks like the problem starts early in reserve_memtype: if (!pat_enabled) { /* This is identical to page table setting without PAT */ if (new_type) { if (req_type == _PAGE_CACHE_WC) *new_type = _PAGE_CACHE_UC_MINUS; else *new_type = req_type & _PAGE_CACHE_MASK; } return 0; } This would be what we want, that is clearing the PWT and PCD flags from the supported flags - if pat_enabled is disabled." This patch does that - disabling PAT. CC: stable@vger.kernel.org # 3.3 and further Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Reported-and-Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reported-and-Tested-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-02-25Merge tag 'stable/for-linus-3.9-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen update from Konrad Rzeszutek Wilk: "This has two new ACPI drivers for Xen - a physical CPU offline/online and a memory hotplug. The way this works is that ACPI kicks the drivers and they make the appropiate hypercall to the hypervisor to tell it that there is a new CPU or memory. There also some changes to the Xen ARM ABIs and couple of fixes. One particularly nasty bug in the Xen PV spinlock code was fixed by Stefan Bader - and has been there since the 2.6.32! Features: - Xen ACPI memory and CPU hotplug drivers - allowing Xen hypervisor to be aware of new CPU and new DIMMs - Cleanups Bug-fixes: - Fixes a long-standing bug in the PV spinlock wherein we did not kick VCPUs that were in a tight loop. - Fixes in the error paths for the event channel machinery" Fix up a few semantic conflicts with the ACPI interface changes in drivers/xen/xen-acpi-{cpu,mem}hotplug.c. * tag 'stable/for-linus-3.9-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: event channel arrays are xen_ulong_t and not unsigned long xen: Send spinlock IPI to all waiters xen: introduce xen_remap, use it instead of ioremap xen: close evtchn port if binding to irq fails xen-evtchn: correct comment and error output xen/tmem: Add missing %s in the printk statement. xen/acpi: move xen_acpi_get_pxm under CONFIG_XEN_DOM0 xen/acpi: ACPI cpu hotplug xen/acpi: Move xen_acpi_get_pxm to Xen's acpi.h xen/stub: driver for CPU hotplug xen/acpi: ACPI memory hotplug xen/stub: driver for memory hotplug xen: implement updated XENMEM_add_to_physmap_range ABI xen/smp: Move the common CPU init code a bit to prep for PVH patch.