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2017-03-17Merge tag 'v4.1.39' into 4.1-2.0.x-imxOtavio Salvador
Linux 4.1.39 * tag 'v4.1.39': (138 commits) Linux 4.1.39 KVM: x86: remove data variable from kvm_get_msr_common KVM: VMX: Fix host initiated access to guest MSR_TSC_AUX KVM: x86: pass host_initiated to functions that read MSRs perf/core: Fix the perf_cpu_time_max_percent check perf/core: Make sysctl_perf_cpu_time_max_percent conform to documentation perf/core: Fix implicitly enable dynamic interrupt throttle perf/core: Fix dynamic interrupt throttle Fix missing sanity check in /dev/sg printk: use rcuidle console tracepoint vfs: fix uninitialized flags in splice_to_pipe() drm/radeon: Use mode h/vdisplay fields to hide out of bounds HW cursor ARM: 8658/1: uaccess: fix zeroing of 64-bit get_user() drm/dp/mst: fix kernel oops when turning off secondary monitor [media] siano: make it work again with CONFIG_VMAP_STACK mmc: core: fix multi-bit bus width without high-speed mode futex: Move futex_init() to core_initcall xen-netfront: Delete rx_refill_timer in xennet_disconnect_backend() scsi: aacraid: Fix INTx/MSI-x issue with older controllers cpumask: use nr_cpumask_bits for parsing functions ... Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
2017-03-06KVM: x86: remove data variable from kvm_get_msr_commonNicolas Iooss
[ Upstream commit b0996ae48285364710bce812e70ce67771ea6ef7 ] Commit 609e36d372ad ("KVM: x86: pass host_initiated to functions that read MSRs") modified kvm_get_msr_common function to use msr_info->data instead of data but missed one occurrence. Replace it and remove the unused local variable. Fixes: 609e36d372ad ("KVM: x86: pass host_initiated to functions that read MSRs") Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2017-03-06KVM: VMX: Fix host initiated access to guest MSR_TSC_AUXHaozhong Zhang
[ Upstream commit 81b1b9ca6d5ca5f3ce91c0095402def657cf5db3 ] The current handling of accesses to guest MSR_TSC_AUX returns error if vcpu does not support rdtscp, though those accesses are initiated by host. This can result in the reboot failure of some versions of QEMU. This patch fixes this issue by passing those host initiated accesses for further handling instead. Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2017-03-06KVM: x86: pass host_initiated to functions that read MSRsPaolo Bonzini
[ Upstream commit 609e36d372ad9329269e4a1467bd35311893d1d6 ] SMBASE is only readable from SMM for the VCPU, but it must be always accessible if userspace is accessing it. Thus, all functions that read MSRs are changed to accept a struct msr_data; the host_initiated and index fields are pre-initialized, while the data field is filled on return. Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2017-03-06KVM: x86: flush pending lapic jump label updates on module unloadDavid Matlack
[ Upstream commit cef84c302fe051744b983a92764d3fcca933415d ] KVM's lapic emulation uses static_key_deferred (apic_{hw,sw}_disabled). These are implemented with delayed_work structs which can still be pending when the KVM module is unloaded. We've seen this cause kernel panics when the kvm_intel module is quickly reloaded. Use the new static_key_deferred_flush() API to flush pending updates on module unload. Signed-off-by: David Matlack <dmatlack@google.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2017-03-06x86/PCI: Ignore _CRS on Supermicro X8DTH-i/6/iF/6FBjorn Helgaas
[ Upstream commit 89e9f7bcd8744ea25fcf0ac671b8d72c10d7d790 ] Martin reported that the Supermicro X8DTH-i/6/iF/6F advertises incorrect host bridge windows via _CRS: pci_root PNP0A08:00: host bridge window [io 0xf000-0xffff] pci_root PNP0A08:01: host bridge window [io 0xf000-0xffff] Both bridges advertise the 0xf000-0xffff window, which cannot be correct. Work around this by ignoring _CRS on this system. The downside is that we may not assign resources correctly to hot-added PCI devices (if they are possible on this system). Link: https://bugzilla.kernel.org/show_bug.cgi?id=42606 Reported-by: Martin Burnicki <martin.burnicki@meinberg.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: stable@vger.kernel.org Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2017-01-23Merge tag 'v4.1.38' into 4.1-2.0.x-imxOtavio Salvador
Linux 4.1.38 * tag 'v4.1.38': (109 commits) Linux 4.1.38 gro: Allow tunnel stacking in the case of FOU/GUE tunnels: Don't apply GRO to multiple layers of encapsulation. net: ipv4: Convert IP network timestamps to be y2038 safe ipip: Properly mark ipip GRO packets as encapsulated. sg_write()/bsg_write() is not fit to be called under KERNEL_DS fs: exec: apply CLOEXEC before changing dumpable task flags IB/cma: Fix a race condition in iboe_addr_get_sgid() Revert "ALSA: usb-audio: Fix race at stopping the stream" kvm: nVMX: Allow L1 to intercept software exceptions (#BP and #OF) drivers/gpu/drm/ast: Fix infinite loop if read fails target/user: Fix use-after-free of tcmu_cmds if they are expired kernel/debug/debug_core.c: more properly delay for secondary CPUs scsi: avoid a permanent stop of the scsi device's request queue IB/multicast: Check ib_find_pkey() return value IPoIB: Avoid reading an uninitialized member variable block_dev: don't test bdev->bd_contains when it is not stable btrfs: limit async_work allocation and worker func duration mm/vmscan.c: set correct defer count for shrinker Input: drv260x - fix input device's parent assignment ...
2017-01-12kvm: nVMX: Allow L1 to intercept software exceptions (#BP and #OF)Jim Mattson
[ Upstream commit ef85b67385436ddc1998f45f1d6a210f935b3388 ] When L2 exits to L0 due to "exception or NMI", software exceptions (#BP and #OF) for which L1 has requested an intercept should be handled by L1 rather than L0. Previously, only hardware exceptions were forwarded to L1. Signed-off-by: Jim Mattson <jmattson@google.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-12-22x86/kexec: add -fno-PIESebastian Andrzej Siewior
[ Upstream commit 90944e40ba1838de4b2a9290cf273f9d76bd3bdd ] If the gcc is configured to do -fPIE by default then the build aborts later with: | Unsupported relocation type: unknown type rel type name (29) Tagging it stable so it is possible to compile recent stable kernels as well. Cc: stable@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Michal Marek <mmarek@suse.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-12-21x86/init: Fix cr4_init_shadow() on CR4-less machinesAndy Lutomirski
[ Upstream commit e1bfc11c5a6f40222a698a818dc269113245820e ] cr4_init_shadow() will panic on 486-like machines without CR4. Fix it using __read_cr4_safe(). Reported-by: david@saggiorato.net Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Fixes: 1e02ce4cccdc ("x86: Store a per-cpu shadow copy of CR4") Link: http://lkml.kernel.org/r/43a20f81fb504013bf613913dc25574b45336a61.1475091074.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-12-17Merge tag 'v4.1.36' into 4.1-2.0.x-imxOtavio Salvador
Linux 4.1.36 * tag 'v4.1.36': (72 commits) Linux 4.1.36 kbuild: add -fno-PIE firewire: net: fix fragmented datagram_size off-by-one firewire: net: guard against rx buffer overflows parisc: Ensure consistent state when switching to kernel stack at syscall entry ovl: fsync after copy-up virtio: console: Unlock vqs while freeing buffers md: be careful not lot leak internal curr_resync value into metadata. -- (all) md: sync sync_completed has correct value as recovery finishes. scsi: arcmsr: Send SYNCHRONIZE_CACHE command to firmware scsi: scsi_debug: Fix memory leak if LBP enabled and module is unloaded drm/radeon/si_dpm: workaround for SI kickers drm/dp/mst: Check peer device type before attempting EDID read drm/dp/mst: add some defines for logical/physical ports drm/dp/mst: Clear port->pdt when tearing down the i2c adapter KVM: MIPS: Precalculate MMIO load resume PC KVM: MIPS: Make ERET handle ERL before EXL drm/radeon: drop register readback in cayman_cp_int_cntl_setup scsi: megaraid_sas: Fix data integrity failure for JBOD (passthrough) devices Revert "drm/radeon: fix DP link training issue with second 4K monitor" ...
2016-11-23kvm: x86: memset whole irq_eoiJiri Slaby
[ Upstream commit 8678654e3c7ad7b0f4beb03fa89691279cba71f9 ] gcc 7 warns: arch/x86/kvm/ioapic.c: In function 'kvm_ioapic_reset': arch/x86/kvm/ioapic.c:597:2: warning: 'memset' used with length equal to number of elements without multiplication by element size [-Wmemset-elt-size] And it is right. Memset whole array using sizeof operator. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: x86@kernel.org Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> [Added x86 subject tag] Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-10-30x86/mm: Expand the exception table logic to allow new handling optionsTony Luck
[ Upstream commit 548acf19234dbda5a52d5a8e7e205af46e9da840 ] Huge amounts of help from Andy Lutomirski and Borislav Petkov to produce this. Andy provided the inspiration to add classes to the exception table with a clever bit-squeezing trick, Boris pointed out how much cleaner it would all be if we just had a new field. Linus Torvalds blessed the expansion with: ' I'd rather not be clever in order to save just a tiny amount of space in the exception table, which isn't really criticial for anybody. ' The third field is another relative function pointer, this one to a handler that executes the actions. We start out with three handlers: 1: Legacy - just jumps the to fixup IP 2: Fault - provide the trap number in %ax to the fixup code 3: Cleaned up legacy for the uaccess error hack Signed-off-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/f6af78fcbd348cf4939875cfda9c19689b5e50b8.1455732970.git.tony.luck@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-10-26Merge tag 'v4.1.35' into 4.1-2.0.x-imxOtavio Salvador
Linux 4.1.35 * tag 'v4.1.35': (98 commits) Linux 4.1.35 xhci: fix usb2 resume timing and races. mm: remove gup_flags FOLL_WRITE games from __get_user_pages() timekeeping: Fix __ktime_get_fast_ns() regression time: Add cycles to nanoseconds translation Linux 4.1.34 openrisc: fix the fix of copy_from_user() avr32: fix 'undefined reference to `___copy_from_user' fix memory leaks in tracing_buffers_splice_read() tracing: Move mutex to protect against resetting of seq data MIPS: SMP: Fix possibility of deadlock when bringing CPUs online MIPS: Fix pre-r6 emulation FPU initialisation btrfs: ensure that file descriptor used with subvol ioctls is a dir fix fault_in_multipages_...() on architectures with no-op access_ok() ocfs2: fix start offset to ocfs2_zero_range_for_truncate() fanotify: fix list corruption in fanotify_get_response() fsnotify: add a way to stop queueing events on group shutdown autofs: use dentry flags to block walks during expire autofs races ocfs2/dlm: fix race between convert and migration ... Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
2016-10-05Merge tag 'v4.1.33' into 4.1-2.0.x-imxOtavio Salvador
Linux 4.1.33 * tag 'v4.1.33': (1760 commits) Linux 4.1.33 Revert "ARC: mm: don't loose PTE_SPECIAL in pte_modify()" x86/AMD: Apply erratum 665 on machines without a BIOS fix x86/paravirt: Do not trace _paravirt_ident_*() functions ovl: listxattr: use strnlen() ovl: remove posix_acl_default from workdir serial: 8250: added acces i/o products quad and octal serial cards sysfs: correctly handle read offset on PREALLOC attrs sysfs: correctly handle short reads on PREALLOC attrs. kernfs: don't depend on d_find_any_alias() when generating notifications dm crypt: fix free of bad values after tfm allocation failure dm crypt: fix error with too large bios dm log writes: fix check of kthread_run() return value dm log writes: fix bug with too large bios dm log writes: move IO accounting earlier to fix error path NFSv4.x: Fix a refcount leak in nfs_callback_up_net xfs: prevent dropping ioend completions during buftarg wait xfs: fix superblock inprogress check USB: serial: option: add WeTelecom 0x6802 and 0x6803 products USB: avoid left shift by -1 ... Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
2016-10-02fix minor infoleak in get_user_ex()Al Viro
[ Upstream commit 1c109fabbd51863475cd12ac206bdd249aee35af ] get_user_ex(x, ptr) should zero x on failure. It's not a lot of a leak (at most we are leaking uninitialized 64bit value off the kernel stack, and in a fairly constrained situation, at that), but the fix is trivial, so... Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> [ This sat in different branch from the uaccess fixes since mid-August ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-09-15x86/AMD: Apply erratum 665 on machines without a BIOS fixEmanuel Czirai
[ Upstream commit d1992996753132e2dafe955cccb2fb0714d3cfc4 ] AMD F12h machines have an erratum which can cause DIV/IDIV to behave unpredictably. The workaround is to set MSRC001_1029[31] but sometimes there is no BIOS update containing that workaround so let's do it ourselves unconditionally. It is simple enough. [ Borislav: Wrote commit message. ] Signed-off-by: Emanuel Czirai <icanrealizeum@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Yaowu Xu <yaowu@google.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20160902053550.18097-1-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-09-15x86/paravirt: Do not trace _paravirt_ident_*() functionsSteven Rostedt
[ Upstream commit 15301a570754c7af60335d094dd2d1808b0641a5 ] Łukasz Daniluk reported that on a RHEL kernel that his machine would lock up after enabling function tracer. I asked him to bisect the functions within available_filter_functions, which he did and it came down to three: _paravirt_nop(), _paravirt_ident_32() and _paravirt_ident_64() It was found that this is only an issue when noreplace-paravirt is added to the kernel command line. This means that those functions are most likely called within critical sections of the funtion tracer, and must not be traced. In newer kenels _paravirt_nop() is defined within gcc asm(), and is no longer an issue. But both _paravirt_ident_{32,64}() causes the following splat when they are traced: mm/pgtable-generic.c:33: bad pmd ffff8800d2435150(0000000001d00054) mm/pgtable-generic.c:33: bad pmd ffff8800d3624190(0000000001d00070) mm/pgtable-generic.c:33: bad pmd ffff8800d36a5110(0000000001d00054) mm/pgtable-generic.c:33: bad pmd ffff880118eb1450(0000000001d00054) NMI watchdog: BUG: soft lockup - CPU#2 stuck for 22s! [systemd-journal:469] Modules linked in: e1000e CPU: 2 PID: 469 Comm: systemd-journal Not tainted 4.6.0-rc4-test+ #513 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012 task: ffff880118f740c0 ti: ffff8800d4aec000 task.ti: ffff8800d4aec000 RIP: 0010:[<ffffffff81134148>] [<ffffffff81134148>] queued_spin_lock_slowpath+0x118/0x1a0 RSP: 0018:ffff8800d4aefb90 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88011eb16d40 RDX: ffffffff82485760 RSI: 000000001f288820 RDI: ffffea0000008030 RBP: ffff8800d4aefb90 R08: 00000000000c0000 R09: 0000000000000000 R10: ffffffff821c8e0e R11: 0000000000000000 R12: ffff880000200fb8 R13: 00007f7a4e3f7000 R14: ffffea000303f600 R15: ffff8800d4b562e0 FS: 00007f7a4e3d7840(0000) GS:ffff88011eb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7a4e3f7000 CR3: 00000000d3e71000 CR4: 00000000001406e0 Call Trace: _raw_spin_lock+0x27/0x30 handle_pte_fault+0x13db/0x16b0 handle_mm_fault+0x312/0x670 __do_page_fault+0x1b1/0x4e0 do_page_fault+0x22/0x30 page_fault+0x28/0x30 __vfs_read+0x28/0xe0 vfs_read+0x86/0x130 SyS_read+0x46/0xa0 entry_SYSCALL_64_fastpath+0x1e/0xa8 Code: 12 48 c1 ea 0c 83 e8 01 83 e2 30 48 98 48 81 c2 40 6d 01 00 48 03 14 c5 80 6a 5d 82 48 89 0a 8b 41 08 85 c0 75 09 f3 90 8b 41 08 <85> c0 74 f7 4c 8b 09 4d 85 c9 74 08 41 0f 18 09 eb 02 f3 90 8b Reported-by: Łukasz Daniluk <lukasz.daniluk@intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-08-31x86/apic: Do not init irq remapping if ioapic is disabledWanpeng Li
[ Upstream commit 2e63ad4bd5dd583871e6602f9d398b9322d358d9 ] native_smp_prepare_cpus -> default_setup_apic_routing -> enable_IR_x2apic -> irq_remapping_prepare -> intel_prepare_irq_remapping -> intel_setup_irq_remapping So IR table is setup even if "noapic" boot parameter is added. As a result we crash later when the interrupt affinity is set due to a half initialized remapping infrastructure. Prevent remap initialization when IOAPIC is disabled. Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Joerg Roedel <joro@8bytes.org> Link: http://lkml.kernel.org/r/1471954039-3942-1-git-send-email-wanpeng.li@hotmail.com Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-08-19perf/x86: Fix undefined shift on 32-bit kernelsAndrey Ryabinin
[ Upstream commit 6d6f2833bfbf296101f9f085e10488aef2601ba5 ] Jim reported: UBSAN: Undefined behaviour in arch/x86/events/intel/core.c:3708:12 shift exponent 35 is too large for 32-bit type 'long unsigned int' The use of 'unsigned long' type obviously is not correct here, make it 'unsigned long long' instead. Reported-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Imre Palik <imrep@amazon.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 2c33645d366d ("perf/x86: Honor the architectural performance monitoring version") Link: http://lkml.kernel.org/r/1462974711-10037-1-git-send-email-aryabinin@virtuozzo.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-08-19x86/syscalls/64: Add compat_sys_keyctl for 32-bit userspaceSasha Levin
[ Upstream commit f7d665627e103e82d34306c7d3f6f46f387c0d8b ] x86_64 needs to use compat_sys_keyctl for 32-bit userspace rather than calling sys_keyctl(). The latter will work in a lot of cases, thereby hiding the issue. Reported-by: Stephan Mueller <smueller@chronox.de> Tested-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: David Howells <dhowells@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keyrings@vger.kernel.org Cc: linux-security-module@vger.kernel.org Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/146961615805.14395.5581949237156769439.stgit@warthog.procyon.org.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-08-19KVM: VMX: handle PML full VMEXIT that occurs during event deliveryCao, Lei
[ Upstream commit b244c9fc251e14a083a1cbf04bef10bd99303a76 ] With PML enabled, guest will shut down if a PML full VMEXIT occurs during event delivery. According to Intel SDM 27.2.3, PML full VMEXIT can occur when event is being delivered through IDT, so KVM should not exit to user space with error. Instead, it should let EXIT_REASON_PML_FULL go through and the event will be re-injected on the next VMENTRY. Signed-off-by: Lei Cao <lei.cao@stratus.com> Cc: stable@vger.kernel.org Fixes: 843e4330573c ("KVM: VMX: Add PML support in VMX") [Shortened the summary and Cc'd stable.] Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-08-19KVM: nVMX: Fix memory corruption when using VMCS shadowingJim Mattson
[ Upstream commit 2f1fe81123f59271bddda673b60116bde9660385 ] When freeing the nested resources of a vcpu, there is an assumption that the vcpu's vmcs01 is the current VMCS on the CPU that executes nested_release_vmcs12(). If this assumption is violated, the vcpu's vmcs01 may be made active on multiple CPUs at the same time, in violation of Intel's specification. Moreover, since the vcpu's vmcs01 is not VMCLEARed on every CPU on which it is active, it can linger in a CPU's VMCS cache after it has been freed and potentially repurposed. Subsequent eviction from the CPU's VMCS cache on a capacity miss can result in memory corruption. It is not sufficient for vmx_free_vcpu() to call vmx_load_vmcs01(). If the vcpu in question was last loaded on a different CPU, it must be migrated to the current CPU before calling vmx_load_vmcs01(). Signed-off-by: Jim Mattson <jmattson@google.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-08-08x86/quirks: Reintroduce scanning of secondary busesLukas Wunner
[ Upstream commit 850c321027c2e31d0afc71588974719a4b565550 ] We used to scan secondary buses until the following commit that was applied in 2009: 8659c406ade3 ("x86: only scan the root bus in early PCI quirks") which commit constrained early quirks to the root bus only. Its motivation was to prevent application of the nvidia_bugs quirk on secondary buses. We're about to add a quirk to reset the Broadcom 4331 wireless card on 2011/2012 Macs, which is located on a secondary bus behind a PCIe root port. To facilitate that, reintroduce scanning of secondary buses. The commit message of 8659c406ade3 notes that scanning only the root bus "saves quite some unnecessary scanning work". The algorithm used prior to 8659c406ade3 was particularly time consuming because it scanned buses 0 to 31 brute force. To avoid lengthening boot time, employ a recursive strategy which only scans buses that are actually reachable from the root bus. Yinghai Lu pointed out that the secondary bus number read from a bridge's config space may be invalid, in particular a value of 0 would cause an infinite loop. The PCI core goes beyond that and recurses to a child bus only if its bus number is greater than the parent bus number (see pci_scan_bridge()). Since the root bus is numbered 0, this implies that secondary buses may not be 0. Do the same on early scanning. If this algorithm is found to significantly impact boot time or cause infinite loops on broken hardware, it would be possible to limit its recursion depth: The Broadcom 4331 quirk applies at depth 1, all others at depth 0, so the bus need not be scanned deeper than that for now. An alternative approach would be to revert to scanning only the root bus, and apply the Broadcom 4331 quirk to the root ports 8086:1c12, 8086:1e12 and 8086:1e16. Apple always positioned the card behind either of these three ports. The quirk would then check presence of the card in slot 0 below the root port and do its deed. Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linux-pci@vger.kernel.org Link: http://lkml.kernel.org/r/f0daa70dac1a9b2483abdb31887173eb6ab77bdf.1465690253.git.lukas@wunner.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-08-08x86/quirks: Apply nvidia_bugs quirk only on root busLukas Wunner
[ Upstream commit 447d29d1d3aed839e74c2401ef63387780ac51ed ] Since the following commit: 8659c406ade3 ("x86: only scan the root bus in early PCI quirks") ... early quirks are only applied to devices on the root bus. The motivation was to prevent application of the nvidia_bugs quirk on secondary buses. We're about to reintroduce scanning of secondary buses for a quirk to reset the Broadcom 4331 wireless card on 2011/2012 Macs. To prevent regressions, open code the requirement to apply nvidia_bugs only on the root bus. Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/4d5477c1d76b2f0387a780f2142bbcdd9fee869b.1465690253.git.lukas@wunner.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-08-06x86/quirks: Add early quirk to reset Apple AirPort cardLukas Wunner
[ Upstream commit abb2bafd295fe962bbadc329dbfb2146457283ac ] The EFI firmware on Macs contains a full-fledged network stack for downloading OS X images from osrecovery.apple.com. Unfortunately on Macs introduced 2011 and 2012, EFI brings up the Broadcom 4331 wireless card on every boot and leaves it enabled even after ExitBootServices has been called. The card continues to assert its IRQ line, causing spurious interrupts if the IRQ is shared. It also corrupts memory by DMAing received packets, allowing for remote code execution over the air. This only stops when a driver is loaded for the wireless card, which may be never if the driver is not installed or blacklisted. The issue seems to be constrained to the Broadcom 4331. Chris Milsted has verified that the newer Broadcom 4360 built into the MacBookPro11,3 (2013/2014) does not exhibit this behaviour. The chances that Apple will ever supply a firmware fix for the older machines appear to be zero. The solution is to reset the card on boot by writing to a reset bit in its mmio space. This must be done as an early quirk and not as a plain vanilla PCI quirk to successfully combat memory corruption by DMAed packets: Matthew Garrett found out in 2012 that the packets are written to EfiBootServicesData memory (http://mjg59.dreamwidth.org/11235.html). This type of memory is made available to the page allocator by efi_free_boot_services(). Plain vanilla PCI quirks run much later, in subsys initcall level. In-between a time window would be open for memory corruption. Random crashes occurring in this time window and attributed to DMAed packets have indeed been observed in the wild by Chris Bainbridge. When Matthew Garrett analyzed the memory corruption issue in 2012, he sought to fix it with a grub quirk which transitions the card to D3hot: http://git.savannah.gnu.org/cgit/grub.git/commit/?id=9d34bb85da56 This approach does not help users with other bootloaders and while it may prevent DMAed packets, it does not cure the spurious interrupts emanating from the card. Unfortunately the card's mmio space is inaccessible in D3hot, so to reset it, we have to undo the effect of Matthew's grub patch and transition the card back to D0. Note that the quirk takes a few shortcuts to reduce the amount of code: The size of BAR 0 and the location of the PM capability is identical on all affected machines and therefore hardcoded. Only the address of BAR 0 differs between models. Also, it is assumed that the BCMA core currently mapped is the 802.11 core. The EFI driver seems to always take care of this. Michael Büsch, Bjorn Helgaas and Matt Fleming contributed feedback towards finding the best solution to this problem. The following should be a comprehensive list of affected models: iMac13,1 2012 21.5" [Root Port 00:1c.3 = 8086:1e16] iMac13,2 2012 27" [Root Port 00:1c.3 = 8086:1e16] Macmini5,1 2011 i5 2.3 GHz [Root Port 00:1c.1 = 8086:1c12] Macmini5,2 2011 i5 2.5 GHz [Root Port 00:1c.1 = 8086:1c12] Macmini5,3 2011 i7 2.0 GHz [Root Port 00:1c.1 = 8086:1c12] Macmini6,1 2012 i5 2.5 GHz [Root Port 00:1c.1 = 8086:1e12] Macmini6,2 2012 i7 2.3 GHz [Root Port 00:1c.1 = 8086:1e12] MacBookPro8,1 2011 13" [Root Port 00:1c.1 = 8086:1c12] MacBookPro8,2 2011 15" [Root Port 00:1c.1 = 8086:1c12] MacBookPro8,3 2011 17" [Root Port 00:1c.1 = 8086:1c12] MacBookPro9,1 2012 15" [Root Port 00:1c.1 = 8086:1e12] MacBookPro9,2 2012 13" [Root Port 00:1c.1 = 8086:1e12] MacBookPro10,1 2012 15" [Root Port 00:1c.1 = 8086:1e12] MacBookPro10,2 2012 13" [Root Port 00:1c.1 = 8086:1e12] For posterity, spurious interrupts caused by the Broadcom 4331 wireless card resulted in splats like this (stacktrace omitted): irq 17: nobody cared (try booting with the "irqpoll" option) handlers: [<ffffffff81374370>] pcie_isr [<ffffffffc0704550>] sdhci_irq [sdhci] threaded [<ffffffffc07013c0>] sdhci_thread_irq [sdhci] [<ffffffffc0a0b960>] azx_interrupt [snd_hda_codec] Disabling IRQ #17 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=79301 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=111781 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=728916 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=895951#c16 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1009819 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1098621 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1149632#c5 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1279130 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1332732 Tested-by: Konstantin Simanov <k.simanov@stlk.ru> # [MacBookPro8,1] Tested-by: Lukas Wunner <lukas@wunner.de> # [MacBookPro9,1] Tested-by: Bryan Paradis <bryan.paradis@gmail.com> # [MacBookPro9,2] Tested-by: Andrew Worsley <amworsley@gmail.com> # [MacBookPro10,1] Tested-by: Chris Bainbridge <chris.bainbridge@gmail.com> # [MacBookPro10,2] Signed-off-by: Lukas Wunner <lukas@wunner.de> Acked-by: Rafał Miłecki <zajec5@gmail.com> Acked-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chris Milsted <cmilsted@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Michael Buesch <m@bues.ch> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: b43-dev@lists.infradead.org Cc: linux-pci@vger.kernel.org Cc: linux-wireless@vger.kernel.org Cc: stable@vger.kernel.org Cc: stable@vger.kernel.org # 123456789abc: x86/quirks: Apply nvidia_bugs quirk only on root bus Cc: stable@vger.kernel.org # 123456789abc: x86/quirks: Reintroduce scanning of secondary buses Link: http://lkml.kernel.org/r/48d0972ac82a53d460e5fce77a07b2560db95203.1465690253.git.lukas@wunner.de [ Did minor readability edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-07-19x86/amd_nb: Fix boot crash on non-AMD systemsBorislav Petkov
[ Upstream commit 1ead852dd88779eda12cb09cc894a03d9abfe1ec ] Fix boot crash that triggers if this driver is built into a kernel and run on non-AMD systems. AMD northbridges users call amd_cache_northbridges() and it returns a negative value to signal that we weren't able to cache/detect any northbridges on the system. At least, it should do so as all its callers expect it to do so. But it does return a negative value only when kmalloc() fails. Fix it to return -ENODEV if there are no NBs cached as otherwise, amd_nb users like amd64_edac, for example, which relies on it to know whether it should load or not, gets loaded on systems like Intel Xeons where it shouldn't. Reported-and-tested-by: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1466097230-5333-2-git-send-email-bp@alien8.de Link: https://lkml.kernel.org/r/5761BEB0.9000807@cybernetics.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
2016-07-10KVM: x86: mask CPUID(0xD,0x1).EAX against host valuePaolo Bonzini
[ Upstream commit 316314cae15fb0e3869b76b468f59a0c83ac3d4e ] This ensures that the guest doesn't see XSAVE extensions (e.g. xgetbv1 or xsavec) that the host lacks. Cc: stable@vger.kernel.org Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10ACPI / processor: Request native thermal interrupt handling via _OSCSrinivas Pandruvada
[ Upstream commit a21211672c9a1d730a39aa65d4a5b3414700adfb ] There are several reports of freeze on enabling HWP (Hardware PStates) feature on Skylake-based systems by the Intel P-states driver. The root cause is identified as the HWP interrupts causing BIOS code to freeze. HWP interrupts use the thermal LVT which can be handled by Linux natively, but on the affected Skylake-based systems SMM will respond to it by default. This is a problem for several reasons: - On the affected systems the SMM thermal LVT handler is broken (it will crash when invoked) and a BIOS update is necessary to fix it. - With thermal interrupt handled in SMM we lose all of the reporting features of the arch/x86/kernel/cpu/mcheck/therm_throt driver. - Some thermal drivers like x86-package-temp depend on the thermal threshold interrupts signaled via the thermal LVT. - The HWP interrupts are useful for debugging and tuning performance (if the kernel can handle them). The native handling of thermal interrupts needs to be enabled because of that. This requires some way to tell SMM that the OS can handle thermal interrupts. That can be done by using _OSC/_PDC in processor scope very early during ACPI initialization. The meaning of _OSC/_PDC bit 12 in processor scope is whether or not the OS supports native handling of interrupts for Collaborative Processor Performance Control (CPPC) notifications. Since on HWP-capable systems CPPC is a firmware interface to HWP, setting this bit effectively tells the firmware that the OS will handle thermal interrupts natively going forward. For details on _OSC/_PDC refer to: http://www.intel.com/content/www/us/en/standards/processor-vendor-specific-acpi-specification.html To implement the _OSC/_PDC handshake as described, introduce a new function, acpi_early_processor_osc(), that walks the ACPI namespace looking for ACPI processor objects and invokes _OSC for them with bit 12 in the capabilities buffer set and terminates the namespace walk on the first success. Also modify intel_thermal_interrupt() to clear HWP status bits in the HWP_STATUS MSR to acknowledge HWP interrupts (which prevents them from firing continuously). Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> [ rjw: Subject & changelog, function rename ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10x86/mm/kmmio: Fix mmiotrace for hugepagesKarol Herbst
[ Upstream commit cfa52c0cfa4d727aa3e457bf29aeff296c528a08 ] Because Linux might use bigger pages than the 4K pages to handle those mmio ioremaps, the kmmio code shouldn't rely on the pade id as it currently does. Using the memory address instead of the page id lets us look up how big the page is and what its base address is, so that we won't get a page fault within the same page twice anymore. Tested-by: Pierre Moreau <pierre.morrow@free.fr> Signed-off-by: Karol Herbst <nouveau@karolherbst.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-mm@kvack.org Cc: linux-x86_64@vger.kernel.org Cc: nouveau@lists.freedesktop.org Cc: pq@iki.fi Cc: rostedt@goodmis.org Link: http://lkml.kernel.org/r/1456966991-6861-1-git-send-email-nouveau@karolherbst.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10kprobes/x86: Clear TF bit in fault on single-steppingMasami Hiramatsu
[ Upstream commit dcfc47248d3f7d28df6f531e6426b933de94370d ] Fix kprobe_fault_handler() to clear the TF (trap flag) bit of the flags register in the case of a fault fixup on single-stepping. If we put a kprobe on the instruction which caused a page fault (e.g. actual mov instructions in copy_user_*), that fault happens on the single-stepping buffer. In this case, kprobes resets running instance so that the CPU can retry execution on the original ip address. However, current code forgets to reset the TF bit. Since this fault happens with TF bit set for enabling single-stepping, when it retries, it causes a debug exception and kprobes can not handle it because it already reset itself. On the most of x86-64 platform, it can be easily reproduced by using kprobe tracer. E.g. # cd /sys/kernel/debug/tracing # echo p copy_user_enhanced_fast_string+5 > kprobe_events # echo 1 > events/kprobes/enable And you'll see a kernel panic on do_debug(), since the debug trap is not handled by kprobes. To fix this problem, we just need to clear the TF bit when resetting running kprobe. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: systemtap@sourceware.org Cc: stable@vger.kernel.org # All the way back to ancient kernels Link: http://lkml.kernel.org/r/20160611140648.25885.37482.stgit@devbox [ Updated the comments. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-06-18x86, build: copy ldlinux.c32 to image.isoH. Peter Anvin
[ Upstream commit 9c77679cadb118c0aa99e6f88533d91765a131ba ] For newer versions of Syslinux, we need ldlinux.c32 in addition to isolinux.bin to reside on the boot disk, so if the latter is found, copy it, too, to the isoimage tree. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Linux Stable Tree <stable@vger.kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-06-17KVM: x86: fix OOPS after invalid KVM_SET_DEBUGREGSPaolo Bonzini
[ Upstream commit d14bdb553f9196169f003058ae1cdabe514470e6 ] MOV to DR6 or DR7 causes a #GP if an attempt is made to write a 1 to any of bits 63:32. However, this is not detected at KVM_SET_DEBUGREGS time, and the next KVM_RUN oopses: general protection fault: 0000 [#1] SMP CPU: 2 PID: 14987 Comm: a.out Not tainted 4.4.9-300.fc23.x86_64 #1 Hardware name: LENOVO 2325F51/2325F51, BIOS G2ET32WW (1.12 ) 05/30/2012 [...] Call Trace: [<ffffffffa072c93d>] kvm_arch_vcpu_ioctl_run+0x141d/0x14e0 [kvm] [<ffffffffa071405d>] kvm_vcpu_ioctl+0x33d/0x620 [kvm] [<ffffffff81241648>] do_vfs_ioctl+0x298/0x480 [<ffffffff812418a9>] SyS_ioctl+0x79/0x90 [<ffffffff817a0f2e>] entry_SYSCALL_64_fastpath+0x12/0x71 Code: 55 83 ff 07 48 89 e5 77 27 89 ff ff 24 fd 90 87 80 81 0f 23 fe 5d c3 0f 23 c6 5d c3 0f 23 ce 5d c3 0f 23 d6 5d c3 0f 23 de 5d c3 <0f> 23 f6 5d c3 0f 0b 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 RIP [<ffffffff810639eb>] native_set_debugreg+0x2b/0x40 RSP <ffff88005836bd50> Testcase (beautified/reduced from syzkaller output): #include <unistd.h> #include <sys/syscall.h> #include <string.h> #include <stdint.h> #include <linux/kvm.h> #include <fcntl.h> #include <sys/ioctl.h> long r[8]; int main() { struct kvm_debugregs dr = { 0 }; r[2] = open("/dev/kvm", O_RDONLY); r[3] = ioctl(r[2], KVM_CREATE_VM, 0); r[4] = ioctl(r[3], KVM_CREATE_VCPU, 7); memcpy(&dr, "\x5d\x6a\x6b\xe8\x57\x3b\x4b\x7e\xcf\x0d\xa1\x72" "\xa3\x4a\x29\x0c\xfc\x6d\x44\x00\xa7\x52\xc7\xd8" "\x00\xdb\x89\x9d\x78\xb5\x54\x6b\x6b\x13\x1c\xe9" "\x5e\xd3\x0e\x40\x6f\xb4\x66\xf7\x5b\xe3\x36\xcb", 48); r[7] = ioctl(r[4], KVM_SET_DEBUGREGS, &dr); r[6] = ioctl(r[4], KVM_RUN, 0); } Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-06-06xen/x86: actually allocate legacy interrupts on PV guestsStefano Stabellini
[ Upstream commit 702f926067d2a4b28c10a3c41a1172dd62d9e735 ] b4ff8389ed14 is incomplete: relies on nr_legacy_irqs() to get the number of legacy interrupts when actually nr_legacy_irqs() returns 0 after probe_8259A(). Use NR_IRQS_LEGACY instead. Signed-off-by: Stefano Stabellini <sstabellini@kernel.org> CC: stable@vger.kernel.org Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-05-30perf/x86/intel/pt: Generate PMI in the STOP region as wellSasha Levin
[ Upstream commit ab92b232ae05c382c3df0e3d6a5c6d16b639ac8c ] Currently, the PT driver always sets the PMI bit one region (page) before the STOP region so that we can wake up the consumer before we run out of room in the buffer and have to disable the event. However, we also need an interrupt in the last output region, so that we actually get to disable the event (if no more room from new data is available at that point), otherwise hardware just quietly refuses to start, but the event is scheduled in and we end up losing trace data till the event gets removed. For a cpu-wide event it is even worse since there may not be any re-scheduling at all and no chance for the ring buffer code to notice that its buffer is filled up and the event needs to be disabled (so that the consumer can re-enable it when it finishes reading the data out). In other words, all the trace data will be lost after the buffer gets filled up. This patch makes PT also generate a PMI when the last output region is full. Reported-by: Markus Metzger <markus.t.metzger@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: vince@deater.net Link: http://lkml.kernel.org/r/1462886313-13660-2-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-05-17x86/tsc: Read all ratio bits from MSR_PLATFORM_INFOChen Yu
[ Upstream commit 886123fb3a8656699dff40afa0573df359abeb18 ] Currently we read the tsc radio: ratio = (MSR_PLATFORM_INFO >> 8) & 0x1f; Thus we get bit 8-12 of MSR_PLATFORM_INFO, however according to the SDM (35.5), the ratio bits are bit 8-15. Ignoring the upper bits can result in an incorrect tsc ratio, which causes the TSC calibration and the Local APIC timer frequency to be incorrect. Fix this problem by masking 0xff instead. [ tglx: Massaged changelog ] Fixes: 7da7c1561366 "x86, tsc: Add static (MSR) TSC calibration on Intel Atom SoCs" Signed-off-by: Chen Yu <yu.c.chen@intel.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: stable@vger.kernel.org Cc: Bin Gao <bin.gao@intel.com> Cc: Len Brown <lenb@kernel.org> Link: http://lkml.kernel.org/r/1462505619-5516-1-git-send-email-yu.c.chen@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-05-17x86/sysfb_efi: Fix valid BAR address range checkWang YanQing
[ Upstream commit c10fcb14c7afd6688c7b197a814358fecf244222 ] The code for checking whether a BAR address range is valid will break out of the loop when a start address of 0x0 is encountered. This behaviour is wrong since by breaking out of the loop we may miss the BAR that describes the EFI frame buffer in a later iteration. Because of this bug I can't use video=efifb: boot parameter to get efifb on my new ThinkPad E550 for my old linux system hard disk with 3.10 kernel. In 3.10, efifb is the only choice due to DRM/I915 not supporting the GPU. This patch also add a trivial optimization to break out after we find the frame buffer address range without testing later BARs. Signed-off-by: Wang YanQing <udknight@gmail.com> [ Rewrote changelog. ] Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Peter Jones <pjones@redhat.com> Cc: <stable@vger.kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1462454061-21561-2-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-05-10x86/mm/xen: Suppress hugetlbfs in PV guestsJan Beulich
[ Upstream commit 103f6112f253017d7062cd74d17f4a514ed4485c ] Huge pages are not normally available to PV guests. Not suppressing hugetlbfs use results in an endless loop of page faults when user mode code tries to access a hugetlbfs mapped area (since the hypervisor denies such PTEs to be created, but error indications can't be propagated out of xen_set_pte_at(), just like for various of its siblings), and - once killed in an oops like this: kernel BUG at .../fs/hugetlbfs/inode.c:428! invalid opcode: 0000 [#1] SMP ... RIP: e030:[<ffffffff811c333b>] [<ffffffff811c333b>] remove_inode_hugepages+0x25b/0x320 ... Call Trace: [<ffffffff811c3415>] hugetlbfs_evict_inode+0x15/0x40 [<ffffffff81167b3d>] evict+0xbd/0x1b0 [<ffffffff8116514a>] __dentry_kill+0x19a/0x1f0 [<ffffffff81165b0e>] dput+0x1fe/0x220 [<ffffffff81150535>] __fput+0x155/0x200 [<ffffffff81079fc0>] task_work_run+0x60/0xa0 [<ffffffff81063510>] do_exit+0x160/0x400 [<ffffffff810637eb>] do_group_exit+0x3b/0xa0 [<ffffffff8106e8bd>] get_signal+0x1ed/0x470 [<ffffffff8100f854>] do_signal+0x14/0x110 [<ffffffff810030e9>] prepare_exit_to_usermode+0xe9/0xf0 [<ffffffff814178a5>] retint_user+0x8/0x13 This is CVE-2016-3961 / XSA-174. Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Juergen Gross <JGross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: stable@vger.kernel.org Cc: xen-devel <xen-devel@lists.xenproject.org> Link: http://lkml.kernel.org/r/57188ED802000078000E431C@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-05-08crypto: sha1-mb - use corrcet pointer while completing jobsXiaodong Liu
[ Upstream commit 0851561d9c965df086ef8a53f981f5f95a57c2c8 ] In sha_complete_job, incorrect mcryptd_hash_request_ctx pointer is used when check and complete other jobs. If the memory of first completed req is freed, while still completing other jobs in the func, kernel will crash since NULL pointer is assigned to RIP. Cc: <stable@vger.kernel.org> Signed-off-by: Xiaodong Liu <xiaodong.liu@intel.com> Acked-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-04-20kvm: x86: do not leak guest xcr0 into host interrupt handlersDavid Matlack
[ Upstream commit fc5b7f3bf1e1414bd4e91db6918c85ace0c873a5 ] An interrupt handler that uses the fpu can kill a KVM VM, if it runs under the following conditions: - the guest's xcr0 register is loaded on the cpu - the guest's fpu context is not loaded - the host is using eagerfpu Note that the guest's xcr0 register and fpu context are not loaded as part of the atomic world switch into "guest mode". They are loaded by KVM while the cpu is still in "host mode". Usage of the fpu in interrupt context is gated by irq_fpu_usable(). The interrupt handler will look something like this: if (irq_fpu_usable()) { kernel_fpu_begin(); [... code that uses the fpu ...] kernel_fpu_end(); } As long as the guest's fpu is not loaded and the host is using eager fpu, irq_fpu_usable() returns true (interrupted_kernel_fpu_idle() returns true). The interrupt handler proceeds to use the fpu with the guest's xcr0 live. kernel_fpu_begin() saves the current fpu context. If this uses XSAVE[OPT], it may leave the xsave area in an undesirable state. According to the SDM, during XSAVE bit i of XSTATE_BV is not modified if bit i is 0 in xcr0. So it's possible that XSTATE_BV[i] == 1 and xcr0[i] == 0 following an XSAVE. kernel_fpu_end() restores the fpu context. Now if any bit i in XSTATE_BV == 1 while xcr0[i] == 0, XRSTOR generates a #GP. The fault is trapped and SIGSEGV is delivered to the current process. Only pre-4.2 kernels appear to be vulnerable to this sequence of events. Commit 653f52c ("kvm,x86: load guest FPU context more eagerly") from 4.2 forces the guest's fpu to always be loaded on eagerfpu hosts. This patch fixes the bug by keeping the host's xcr0 loaded outside of the interrupts-disabled region where KVM switches into guest mode. Cc: stable@vger.kernel.org Suggested-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: David Matlack <dmatlack@google.com> [Move load after goto cancel_injection. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-04-20KVM: x86: Inject pending interrupt even if pending nmi existYuki Shibuya
[ Upstream commit 321c5658c5e9192dea0d58ab67cf1791e45b2b26 ] Non maskable interrupts (NMI) are preferred to interrupts in current implementation. If a NMI is pending and NMI is blocked by the result of nmi_allowed(), pending interrupt is not injected and enable_irq_window() is not executed, even if interrupts injection is allowed. In old kernel (e.g. 2.6.32), schedule() is often called in NMI context. In this case, interrupts are needed to execute iret that intends end of NMI. The flag of blocking new NMI is not cleared until the guest execute the iret, and interrupts are blocked by pending NMI. Due to this, iret can't be invoked in the guest, and the guest is starved until block is cleared by some events (e.g. canceling injection). This patch injects pending interrupts, when it's allowed, even if NMI is blocked. And, If an interrupts is pending after executing inject_pending_event(), enable_irq_window() is executed regardless of NMI pending counter. Cc: stable@vger.kernel.org Signed-off-by: Yuki Shibuya <shibuya.yk@ncos.nec.co.jp> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-04-18KVM: VMX: avoid guest hang on invalid invept instructionPaolo Bonzini
[ Upstream commit 2849eb4f99d54925c543db12917127f88b3c38ff ] A guest executing an invalid invept instruction would hang because the instruction pointer was not updated. Cc: stable@vger.kernel.org Fixes: bfd0a56b90005f8c8a004baf407ad90045c2b11e Reviewed-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-04-18x86/apic: Fix suspicious RCU usage in smp_trace_call_function_interrupt()Dave Jones
[ Upstream commit 7834c10313fb823e538f2772be78edcdeed2e6e3 ] Since 4.4, I've been able to trigger this occasionally: =============================== [ INFO: suspicious RCU usage. ] 4.5.0-rc7-think+ #3 Not tainted Cc: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/20160315012054.GA17765@codemonkey.org.uk Signed-off-by: Thomas Gleixner <tglx@linutronix.de> ------------------------------- ./arch/x86/include/asm/msr-trace.h:47 suspicious rcu_dereference_check() usage! other info that might help us debug this: RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 1 RCU used illegally from extended quiescent state! no locks held by swapper/3/0. stack backtrace: CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.5.0-rc7-think+ #3 ffffffff92f821e0 1f3e5c340597d7fc ffff880468e07f10 ffffffff92560c2a ffff880462145280 0000000000000001 ffff880468e07f40 ffffffff921376a6 ffffffff93665ea0 0000cc7c876d28da 0000000000000005 ffffffff9383dd60 Call Trace: <IRQ> [<ffffffff92560c2a>] dump_stack+0x67/0x9d [<ffffffff921376a6>] lockdep_rcu_suspicious+0xe6/0x100 [<ffffffff925ae7a7>] do_trace_write_msr+0x127/0x1a0 [<ffffffff92061c83>] native_apic_msr_eoi_write+0x23/0x30 [<ffffffff92054408>] smp_trace_call_function_interrupt+0x38/0x360 [<ffffffff92d1ca60>] trace_call_function_interrupt+0x90/0xa0 <EOI> [<ffffffff92ac5124>] ? cpuidle_enter_state+0x1b4/0x520 Move the entering_irq() call before ack_APIC_irq(), because entering_irq() tells the RCU susbstems to end the extended quiescent state, so that the following trace call in ack_APIC_irq() works correctly. Suggested-by: Andi Kleen <ak@linux.intel.com> Fixes: 4787c368a9bc "x86/tracing: Add irq_enter/exit() in smp_trace_reschedule_interrupt()" Signed-off-by: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-04-18x86/iopl: Fix iopl capability check on Xen PVAndy Lutomirski
[ Upstream commit c29016cf41fe9fa994a5ecca607cf5f1cd98801e ] iopl(3) is supposed to work if iopl is already 3, even if unprivileged. This didn't work right on Xen PV. Fix it. Reviewewd-by: Jan Beulich <JBeulich@suse.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/8ce12013e6e4c0a44a97e316be4a6faff31bd5ea.1458162709.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-04-18x86/PCI: Mark Broadwell-EP Home Agent & PCU as having non-compliant BARsBjorn Helgaas
[ Upstream commit b894157145e4ac7598d7062bc93320898a5e059e ] The Home Agent and PCU PCI devices in Broadwell-EP have a non-BAR register where a BAR should be. We don't know what the side effects of sizing the "BAR" would be, and we don't know what address space the "BAR" might appear to describe. Mark these devices as having non-compliant BARs so the PCI core doesn't touch them. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: Andi Kleen <ak@linux.intel.com> CC: stable@vger.kernel.org Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-04-18perf/x86/intel: Add definition for PT PMI bitStephane Eranian
[ Upstream commit 5690ae28e472d25e330ad0c637a5cea3fc39fb32 ] This patch adds a definition for GLOBAL_OVFL_STATUS bit 55 which is used with the Processor Trace (PT) feature. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: adrian.hunter@intel.com Cc: kan.liang@intel.com Cc: namhyung@kernel.org Link: http://lkml.kernel.org/r/1457034642-21837-2-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-04-18x86: Add new MSRs and MSR bits used for Intel Skylake PMU supportAndi Kleen
[ Upstream commit b83ff1c8617aac03a1cf807aafa848fe0f0908f2 ] Add new MSRs (LBR_INFO) and some new MSR bits used by the Intel Skylake PMU driver. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: eranian@google.com Link: http://lkml.kernel.org/r/1431285767-27027-4-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-04-18KVM: i8254: change PIT discard tick policyRadim Krčmář
[ Upstream commit 7dd0fdff145c5be7146d0ac06732ae3613412ac1 ] Discard policy uses ack_notifiers to prevent injection of PIT interrupts before EOI from the last one. This patch changes the policy to always try to deliver the interrupt, which makes a difference when its vector is in ISR. Old implementation would drop the interrupt, but proposed one injects to IRR, like real hardware would. The old policy breaks legacy NMI watchdogs, where PIT is used through virtual wire (LVT0): PIT never sends an interrupt before receiving EOI, thus a guest deadlock with disabled interrupts will stop NMIs. Note that NMI doesn't do EOI, so PIT also had to send a normal interrupt through IOAPIC. (KVM's PIT is deeply rotten and luckily not used much in modern systems.) Even though there is a chance of regressions, I think we can fix the LVT0 NMI bug without introducing a new tick policy. Cc: <stable@vger.kernel.org> Reported-by: Yuki Shibuya <shibuya.yk@ncos.nec.co.jp> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-04-18x86/iopl/64: Properly context-switch IOPL on Xen PVAndy Lutomirski
commit b7a584598aea7ca73140cb87b40319944dd3393f upstream. On Xen PV, regs->flags doesn't reliably reflect IOPL and the exit-to-userspace code doesn't change IOPL. We need to context switch it manually. I'm doing this without going through paravirt because this is specific to Xen PV. After the dust settles, we can merge this with the 32-bit code, tidy up the iopl syscall implementation, and remove the set_iopl pvop entirely. Fixes XSA-171. Reviewewd-by: Jan Beulich <JBeulich@suse.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/693c3bd7aeb4d3c27c92c622b7d0f554a458173c.1458162709.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> [ kamal: backport to 4.2-stable: no X86_FEATURE_XENPV so just call xen_pv_domain() directly ] Acked-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-04-13KVM: x86: Reload pit counters for all channels when restoring stateAndrew Honig
[ Upstream commit 0185604c2d82c560dab2f2933a18f797e74ab5a8 ] Currently if userspace restores the pit counters with a count of 0 on channels 1 or 2 and the guest attempts to read the count on those channels, then KVM will perform a mod of 0 and crash. This will ensure that 0 values are converted to 65536 as per the spec. This is CVE-2015-7513. Signed-off-by: Andy Honig <ahonig@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>