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2021-04-04Merge branch 'master-upstream'Bruce Ashfield
2021-04-02Merge tag 'acpi-5.12-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI fixes from Rafael Wysocki: "These fix an ACPI tables management issue, an issue related to the ACPI enumeration of devices and CPU wakeup in the ACPI processor driver. Specifics: - Ensure that the memory occupied by ACPI tables on x86 will always be reserved to prevent it from being allocated for other purposes which was possible in some cases (Rafael Wysocki). - Fix the ACPI device enumeration code to prevent it from attempting to evaluate the _STA control method for devices with unmet dependencies which is likely to fail (Hans de Goede). - Fix the handling of CPU0 wakeup in the ACPI processor driver to prevent CPU0 online failures from occurring (Vitaly Kuznetsov)" * tag 'acpi-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI: processor: Fix CPU0 wakeup in acpi_idle_play_dead() ACPI: scan: Fix _STA getting called on devices with unmet dependencies ACPI: tables: x86: Reserve memory occupied by ACPI tables
2021-04-02Merge branches 'acpi-tables' and 'acpi-scan'Rafael J. Wysocki
* acpi-tables: ACPI: tables: x86: Reserve memory occupied by ACPI tables * acpi-scan: ACPI: scan: Fix _STA getting called on devices with unmet dependencies
2021-04-01ACPI: processor: Fix CPU0 wakeup in acpi_idle_play_dead()Vitaly Kuznetsov
Commit 496121c02127 ("ACPI: processor: idle: Allow probing on platforms with one ACPI C-state") broke CPU0 hotplug on certain systems, e.g. I'm observing the following on AWS Nitro (e.g r5b.xlarge but other instance types are affected as well): # echo 0 > /sys/devices/system/cpu/cpu0/online # echo 1 > /sys/devices/system/cpu/cpu0/online <10 seconds delay> -bash: echo: write error: Input/output error In fact, the above mentioned commit only revealed the problem and did not introduce it. On x86, to wakeup CPU an NMI is being used and hlt_play_dead()/mwait_play_dead() loops are prepared to handle it: /* * If NMI wants to wake up CPU0, start CPU0. */ if (wakeup_cpu0()) start_cpu0(); cpuidle_play_dead() -> acpi_idle_play_dead() (which is now being called on systems where it wasn't called before the above mentioned commit) serves the same purpose but it doesn't have a path for CPU0. What happens now on wakeup is: - NMI is sent to CPU0 - wakeup_cpu0_nmi() works as expected - we get back to while (1) loop in acpi_idle_play_dead() - safe_halt() puts CPU0 to sleep again. The straightforward/minimal fix is add the special handling for CPU0 on x86 and that's what the patch is doing. Fixes: 496121c02127 ("ACPI: processor: idle: Allow probing on platforms with one ACPI C-state") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: 5.10+ <stable@vger.kernel.org> # 5.10+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-04-01KVM: x86: Prevent 'hv_clock->system_time' from going negative in ↵Vitaly Kuznetsov
kvm_guest_time_update() When guest time is reset with KVM_SET_CLOCK(0), it is possible for 'hv_clock->system_time' to become a small negative number. This happens because in KVM_SET_CLOCK handling we set 'kvm->arch.kvmclock_offset' based on get_kvmclock_ns(kvm) but when KVM_REQ_CLOCK_UPDATE is handled, kvm_guest_time_update() does (masterclock in use case): hv_clock.system_time = ka->master_kernel_ns + v->kvm->arch.kvmclock_offset; And 'master_kernel_ns' represents the last time when masterclock got updated, it can precede KVM_SET_CLOCK() call. Normally, this is not a problem, the difference is very small, e.g. I'm observing hv_clock.system_time = -70 ns. The issue comes from the fact that 'hv_clock.system_time' is stored as unsigned and 'system_time / 100' in compute_tsc_page_parameters() becomes a very big number. Use 'master_kernel_ns' instead of get_kvmclock_ns() when masterclock is in use and get_kvmclock_base_ns() when it's not to prevent 'system_time' from going negative. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210331124130.337992-2-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-04-01KVM: x86: disable interrupts while pvclock_gtod_sync_lock is takenPaolo Bonzini
pvclock_gtod_sync_lock can be taken with interrupts disabled if the preempt notifier calls get_kvmclock_ns to update the Xen runstate information: spin_lock include/linux/spinlock.h:354 [inline] get_kvmclock_ns+0x25/0x390 arch/x86/kvm/x86.c:2587 kvm_xen_update_runstate+0x3d/0x2c0 arch/x86/kvm/xen.c:69 kvm_xen_update_runstate_guest+0x74/0x320 arch/x86/kvm/xen.c:100 kvm_xen_runstate_set_preempted arch/x86/kvm/xen.h:96 [inline] kvm_arch_vcpu_put+0x2d8/0x5a0 arch/x86/kvm/x86.c:4062 So change the users of the spinlock to spin_lock_irqsave and spin_unlock_irqrestore. Reported-by: syzbot+b282b65c2c68492df769@syzkaller.appspotmail.com Fixes: 30b5c851af79 ("KVM: x86/xen: Add support for vCPU runstate information") Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-04-01KVM: x86: reduce pvclock_gtod_sync_lock critical sectionsPaolo Bonzini
There is no need to include changes to vcpu->requests into the pvclock_gtod_sync_lock critical section. The changes to the shared data structures (in pvclock_update_vm_gtod_copy) already occur under the lock. Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-04-01Merge branch 'kvm-fix-svm-races' into kvm-masterPaolo Bonzini
2021-04-01KVM: SVM: ensure that EFER.SVME is set when running nested guest or on ↵Paolo Bonzini
nested vmexit Fixing nested_vmcb_check_save to avoid all TOC/TOU races is a bit harder in released kernels, so do the bare minimum by avoiding that EFER.SVME is cleared. This is problematic because svm_set_efer frees the data structures for nested virtualization if EFER.SVME is cleared. Also check that EFER.SVME remains set after a nested vmexit; clearing it could happen if the bit is zero in the save area that is passed to KVM_SET_NESTED_STATE (the save area of the nested state corresponds to the nested hypervisor's state and is restored on the next nested vmexit). Cc: stable@vger.kernel.org Fixes: 2fcf4876ada ("KVM: nSVM: implement on demand allocation of the nested state") Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-04-01KVM: SVM: load control fields from VMCB12 before checking themPaolo Bonzini
Avoid races between check and use of the nested VMCB controls. This for example ensures that the VMRUN intercept is always reflected to the nested hypervisor, instead of being processed by the host. Without this patch, it is possible to end up with svm->nested.hsave pointing to the MSR permission bitmap for nested guests. This bug is CVE-2021-29657. Reported-by: Felix Wilhelm <fwilhelm@google.com> Cc: stable@vger.kernel.org Fixes: 2fcf4876ada ("KVM: nSVM: implement on demand allocation of the nested state") Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-31Merge commit 'kvm-tdp-fix-flushes' into kvm-masterPaolo Bonzini
2021-03-30KVM: x86/mmu: Don't allow TDP MMU to yield when recovering NX pagesSean Christopherson
Prevent the TDP MMU from yielding when zapping a gfn range during NX page recovery. If a flush is pending from a previous invocation of the zapping helper, either in the TDP MMU or the legacy MMU, but the TDP MMU has not accumulated a flush for the current invocation, then yielding will release mmu_lock with stale TLB entries. That being said, this isn't technically a bug fix in the current code, as the TDP MMU will never yield in this case. tdp_mmu_iter_cond_resched() will yield if and only if it has made forward progress, as defined by the current gfn vs. the last yielded (or starting) gfn. Because zapping a single shadow page is guaranteed to (a) find that page and (b) step sideways at the level of the shadow page, the TDP iter will break its loop before getting a chance to yield. But that is all very, very subtle, and will break at the slightest sneeze, e.g. zapping while holding mmu_lock for read would break as the TDP MMU wouldn't be guaranteed to see the present shadow page, and thus could step sideways at a lower level. Cc: Ben Gardon <bgardon@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210325200119.1359384-4-seanjc@google.com> [Add lockdep assertion. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-30KVM: x86/mmu: Ensure TLBs are flushed for TDP MMU during NX zappingSean Christopherson
Honor the "flush needed" return from kvm_tdp_mmu_zap_gfn_range(), which does the flush itself if and only if it yields (which it will never do in this particular scenario), and otherwise expects the caller to do the flush. If pages are zapped from the TDP MMU but not the legacy MMU, then no flush will occur. Fixes: 29cf0f5007a2 ("kvm: x86/mmu: NX largepage recovery for TDP MMU") Cc: stable@vger.kernel.org Cc: Ben Gardon <bgardon@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210325200119.1359384-3-seanjc@google.com> Reviewed-by: Ben Gardon <bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-30KVM: x86/mmu: Ensure TLBs are flushed when yielding during GFN range zapSean Christopherson
When flushing a range of GFNs across multiple roots, ensure any pending flush from a previous root is honored before yielding while walking the tables of the current root. Note, kvm_tdp_mmu_zap_gfn_range() now intentionally overwrites its local "flush" with the result to avoid redundant flushes. zap_gfn_range() preserves and return the incoming "flush", unless of course the flush was performed prior to yielding and no new flush was triggered. Fixes: 1af4a96025b3 ("KVM: x86/mmu: Yield in TDU MMU iter even if no SPTES changed") Cc: stable@vger.kernel.org Reviewed-by: Ben Gardon <bgardon@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210325200119.1359384-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-30KVM: make: Fix out-of-source module buildsSiddharth Chandrasekaran
Building kvm module out-of-source with, make -C $SRC O=$BIN M=arch/x86/kvm fails to find "irq.h" as the include dir passed to cflags-y does not prefix the source dir. Fix this by prefixing $(srctree) to the include dir path. Signed-off-by: Siddharth Chandrasekaran <sidcha@amazon.de> Message-Id: <20210324124347.18336-1-sidcha@amazon.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-30KVM: x86/vPMU: Forbid writing to MSR_F15H_PERF MSRs when guest doesn't have ↵Vitaly Kuznetsov
X86_FEATURE_PERFCTR_CORE MSR_F15H_PERF_CTL0-5, MSR_F15H_PERF_CTR0-5 MSRs are only available when X86_FEATURE_PERFCTR_CORE CPUID bit was exposed to the guest. KVM, however, allows these MSRs unconditionally because kvm_pmu_is_valid_msr() -> amd_msr_idx_to_pmc() check always passes and because kvm_pmu_set_msr() -> amd_pmu_set_msr() doesn't fail. In case of a counter (CTRn), no big harm is done as we only increase internal PMC's value but in case of an eventsel (CTLn), we go deep into perf internals with a non-existing counter. Note, kvm_get_msr_common() just returns '0' when these MSRs don't exist and this also seems to contradict architectural behavior which is #GP (I did check one old Opteron host) but changing this status quo is a bit scarier. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210323084515.1346540-1-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-30KVM: x86: remove unused declaration of kvm_write_tsc()Dongli Zhang
kvm_write_tsc() was renamed and made static since commit 0c899c25d754 ("KVM: x86: do not attempt TSC synchronization on guest writes"). Remove its unused declaration. Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Message-Id: <20210326070334.12310-1-dongli.zhang@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-30KVM: clean up the unused argumentHaiwei Li
kvm_msr_ignored_check function never uses vcpu argument. Clean up the function and invokers. Signed-off-by: Haiwei Li <lihaiwei@tencent.com> Message-Id: <20210313051032.4171-1-lihaiwei.kernel@gmail.com> Reviewed-by: Keqian Zhu <zhukeqian1@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-29ACPI: tables: x86: Reserve memory occupied by ACPI tablesRafael J. Wysocki
The following problem has been reported by George Kennedy: Since commit 7fef431be9c9 ("mm/page_alloc: place pages to tail in __free_pages_core()") the following use after free occurs intermittently when ACPI tables are accessed. BUG: KASAN: use-after-free in ibft_init+0x134/0xc49 Read of size 4 at addr ffff8880be453004 by task swapper/0/1 CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.12.0-rc1-7a7fd0d #1 Call Trace: dump_stack+0xf6/0x158 print_address_description.constprop.9+0x41/0x60 kasan_report.cold.14+0x7b/0xd4 __asan_report_load_n_noabort+0xf/0x20 ibft_init+0x134/0xc49 do_one_initcall+0xc4/0x3e0 kernel_init_freeable+0x5af/0x66b kernel_init+0x16/0x1d0 ret_from_fork+0x22/0x30 ACPI tables mapped via kmap() do not have their mapped pages reserved and the pages can be "stolen" by the buddy allocator. Apparently, on the affected system, the ACPI table in question is not located in "reserved" memory, like ACPI NVS or ACPI Data, that will not be used by the buddy allocator, so the memory occupied by that table has to be explicitly reserved to prevent the buddy allocator from using it. In order to address this problem, rearrange the initialization of the ACPI tables on x86 to locate the initial tables earlier and reserve the memory occupied by them. The other architectures using ACPI should not be affected by this change. Link: https://lore.kernel.org/linux-acpi/1614802160-29362-1-git-send-email-george.kennedy@oracle.com/ Reported-by: George Kennedy <george.kennedy@oracle.com> Tested-by: George Kennedy <george.kennedy@oracle.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Cc: 5.10+ <stable@vger.kernel.org> # 5.10+
2021-03-28Merge tag 'x86-urgent-2021-03-28' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Two fixes: - Fix build failure on Ubuntu with new GCC packages that turn on -fcf-protection - Fix SME memory encryption PTE encoding bug - AFAICT the code worked on 4K page sizes (level 1) but had the wrong shift at higher page level orders (level 2 and higher)" * tag 'x86-urgent-2021-03-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/build: Turn off -fcf-protection for realmode targets x86/mem_encrypt: Correct physical address calculation in __set_clr_pte_enc()
2021-03-26Merge tag 'for-linus-5.12b-rc5-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: "This contains a small series with a more elegant fix of a problem which was originally fixed in rc2" * tag 'for-linus-5.12b-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: Revert "xen: fix p2m size in dom0 for disabled memory hotplug case" xen/x86: make XEN_BALLOON_MEMORY_HOTPLUG_LIMIT depend on MEMORY_HOTPLUG
2021-03-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds
Pull networking fixes from David Miller: "Various fixes, all over: 1) Fix overflow in ptp_qoriq_adjfine(), from Yangbo Lu. 2) Always store the rx queue mapping in veth, from Maciej Fijalkowski. 3) Don't allow vmlinux btf in map_create, from Alexei Starovoitov. 4) Fix memory leak in octeontx2-af from Colin Ian King. 5) Use kvalloc in bpf x86 JIT for storing jit'd addresses, from Yonghong Song. 6) Fix tx ptp stats in mlx5, from Aya Levin. 7) Check correct ip version in tun decap, fropm Roi Dayan. 8) Fix rate calculation in mlx5 E-Switch code, from arav Pandit. 9) Work item memork leak in mlx5, from Shay Drory. 10) Fix ip6ip6 tunnel crash with bpf, from Daniel Borkmann. 11) Lack of preemptrion awareness in macvlan, from Eric Dumazet. 12) Fix data race in pxa168_eth, from Pavel Andrianov. 13) Range validate stab in red_check_params(), from Eric Dumazet. 14) Inherit vlan filtering setting properly in b53 driver, from Florian Fainelli. 15) Fix rtnl locking in igc driver, from Sasha Neftin. 16) Pause handling fixes in igc driver, from Muhammad Husaini Zulkifli. 17) Missing rtnl locking in e1000_reset_task, from Vitaly Lifshits. 18) Use after free in qlcnic, from Lv Yunlong. 19) fix crash in fritzpci mISDN, from Tong Zhang. 20) Premature rx buffer reuse in igb, from Li RongQing. 21) Missing termination of ip[a driver message handler arrays, from Alex Elder. 22) Fix race between "x25_close" and "x25_xmit"/"x25_rx" in hdlc_x25 driver, from Xie He. 23) Use after free in c_can_pci_remove(), from Tong Zhang. 24) Uninitialized variable use in nl80211, from Jarod Wilson. 25) Off by one size calc in bpf verifier, from Piotr Krysiuk. 26) Use delayed work instead of deferrable for flowtable GC, from Yinjun Zhang. 27) Fix infinite loop in NPC unmap of octeontx2 driver, from Hariprasad Kelam. 28) Fix being unable to change MTU of dwmac-sun8i devices due to lack of fifo sizes, from Corentin Labbe. 29) DMA use after free in r8169 with WoL, fom Heiner Kallweit. 30) Mismatched prototypes in isdn-capi, from Arnd Bergmann. 31) Fix psample UAPI breakage, from Ido Schimmel" * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (171 commits) psample: Fix user API breakage math: Export mul_u64_u64_div_u64 ch_ktls: fix enum-conversion warning octeontx2-af: Fix memory leak of object buf ptp_qoriq: fix overflow in ptp_qoriq_adjfine() u64 calcalation net: bridge: don't notify switchdev for local FDB addresses net/sched: act_ct: clear post_ct if doing ct_clear net: dsa: don't assign an error value to tag_ops isdn: capi: fix mismatched prototypes net/mlx5: SF, do not use ecpu bit for vhca state processing net/mlx5e: Fix division by 0 in mlx5e_select_queue net/mlx5e: Fix error path for ethtool set-priv-flag net/mlx5e: Offload tuple rewrite for non-CT flows net/mlx5e: Allow to match on MPLS parameters only for MPLS over UDP net/mlx5: Add back multicast stats for uplink representor net: ipconfig: ic_dev can be NULL in ic_close_devs MAINTAINERS: Combine "QLOGIC QLGE 10Gb ETHERNET DRIVER" sections into one docs: networking: Fix a typo r8169: fix DMA being used after buffer free if WoL is enabled net: ipa: fix init header command validation ...
2021-03-24Revert "xen: fix p2m size in dom0 for disabled memory hotplug case"Roger Pau Monne
This partially reverts commit 882213990d32 ("xen: fix p2m size in dom0 for disabled memory hotplug case") There's no need to special case XEN_UNPOPULATED_ALLOC anymore in order to correctly size the p2m. The generic memory hotplug option has already been tied together with the Xen hotplug limit, so enabling memory hotplug should already trigger a properly sized p2m on Xen PV. Note that XEN_UNPOPULATED_ALLOC depends on ZONE_DEVICE which pulls in MEMORY_HOTPLUG. Leave the check added to __set_phys_to_machine and the adjusted comment about EXTRA_MEM_RATIO. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20210324122424.58685-3-roger.pau@citrix.com [boris: fixed formatting issues] Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-03-24xen/x86: make XEN_BALLOON_MEMORY_HOTPLUG_LIMIT depend on MEMORY_HOTPLUGRoger Pau Monne
The Xen memory hotplug limit should depend on the memory hotplug generic option, rather than the Xen balloon configuration. It's possible to have a kernel with generic memory hotplug enabled, but without Xen balloon enabled, at which point memory hotplug won't work correctly due to the size limitation of the p2m. Rename the option to XEN_MEMORY_HOTPLUG_LIMIT since it's no longer tied to ballooning. Fixes: 9e2369c06c8a18 ("xen: add helpers to allocate unpopulated memory") Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20210324122424.58685-2-roger.pau@citrix.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-03-23x86/build: Turn off -fcf-protection for realmode targetsArnd Bergmann
The new Ubuntu GCC packages turn on -fcf-protection globally, which causes a build failure in the x86 realmode code: cc1: error: ‘-fcf-protection’ is not compatible with this target Turn it off explicitly on compilers that understand this option. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20210323124846.1584944-1-arnd@kernel.org
2021-03-23x86/mem_encrypt: Correct physical address calculation in __set_clr_pte_enc()Isaku Yamahata
The pfn variable contains the page frame number as returned by the pXX_pfn() functions, shifted to the right by PAGE_SHIFT to remove the page bits. After page protection computations are done to it, it gets shifted back to the physical address using page_level_shift(). That is wrong, of course, because that function determines the shift length based on the level of the page in the page table but in all the cases, it was shifted by PAGE_SHIFT before. Therefore, shift it back using PAGE_SHIFT to get the correct physical address. [ bp: Rewrite commit message. ] Fixes: dfaaec9033b8 ("x86: Add support for changing memory encryption attribute in early boot") Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/81abbae1657053eccc535c16151f63cd049dcb97.1616098294.git.isaku.yamahata@intel.com
2021-03-22Merge tag 'v5.12-rc4'Bruce Ashfield
Linux 5.12-rc4
2021-03-21Merge tag 'perf-urgent-2021-03-21' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Boundary condition fixes for bugs unearthed by the perf fuzzer" * tag 'perf-urgent-2021-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel: Fix unchecked MSR access error caused by VLBR_EVENT perf/x86/intel: Fix a crash caused by zero PEBS status
2021-03-21Merge tag 'x86_urgent_for_v5.12-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: "The freshest pile of shiny x86 fixes for 5.12: - Add the arch-specific mapping between physical and logical CPUs to fix devicetree-node lookups - Restore the IRQ2 ignore logic - Fix get_nr_restart_syscall() to return the correct restart syscall number. Split in a 4-patches set to avoid kABI breakage when backporting to dead kernels" * tag 'x86_urgent_for_v5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic/of: Fix CPU devicetree-node lookups x86/ioapic: Ignore IRQ2 again x86: Introduce restart_block->arch_data to remove TS_COMPAT_RESTART x86: Introduce TS_COMPAT_RESTART to fix get_nr_restart_syscall() x86: Move TS_COMPAT back to asm/thread_info.h kernel, fs: Introduce and use set_restart_fn() and arch_set_restart_data()
2021-03-20Merge tag 'riscv-for-linus-5.12-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: "A handful of fixes for 5.12: - fix the SBI remote fence numbers for hypervisor fences, which had been transcribed in the wrong order in Linux. These fences are only used with the KVM patches applied. - fix a whole host of build warnings, these should have no functional change. - fix init_resources() to prevent an off-by-one error from causing an out-of-bounds array reference. This was manifesting during boot on vexriscv. - ensure the KASAN mappings are visible before proceeding to use them" * tag 'riscv-for-linus-5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: Correct SPARSEMEM configuration RISC-V: kasan: Declare kasan_shallow_populate() static riscv: Ensure page table writes are flushed when initializing KASAN vmalloc RISC-V: Fix out-of-bounds accesses in init_resources() riscv: Fix compilation error with Canaan SoC ftrace: Fix spelling mistake "disabed" -> "disabled" riscv: fix bugon.cocci warnings riscv: process: Fix no prototype for arch_dup_task_struct riscv: ftrace: Use ftrace_get_regs helper riscv: process: Fix no prototype for show_regs riscv: syscall_table: Reduce W=1 compilation warnings noise riscv: time: Fix no prototype for time_init riscv: ptrace: Fix no prototype warnings riscv: sbi: Fix comment of __sbi_set_timer_v01 riscv: irq: Fix no prototype warning riscv: traps: Fix no prototype warnings RISC-V: correct enum sbi_ext_rfence_fid
2021-03-19bpf: Use NOP_ATOMIC5 instead of emit_nops(&prog, 5) for BPF_TRAMP_F_CALL_ORIGStanislav Fomichev
__bpf_arch_text_poke does rewrite only for atomic nop5, emit_nops(xxx, 5) emits non-atomic one which breaks fentry/fexit with k8 atomics: P6_NOP5 == P6_NOP5_ATOMIC (0f1f440000 == 0f1f440000) K8_NOP5 != K8_NOP5_ATOMIC (6666906690 != 6666666690) Can be reproduced by doing "ideal_nops = k8_nops" in "arch_init_ideal_nops() and running fexit_bpf2bpf selftest. Fixes: e21aa341785c ("bpf: Fix fexit trampoline.") Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210320000001.915366-1-sdf@google.com
2021-03-19x86/apic/of: Fix CPU devicetree-node lookupsJohan Hovold
Architectures that describe the CPU topology in devicetree and do not have an identity mapping between physical and logical CPU ids must override the default implementation of arch_match_cpu_phys_id(). Failing to do so breaks CPU devicetree-node lookups using of_get_cpu_node() and of_cpu_device_node_get() which several drivers rely on. It also causes the CPU struct devices exported through sysfs to point to the wrong devicetree nodes. On x86, CPUs are described in devicetree using their APIC ids and those do not generally coincide with the logical ids, even if CPU0 typically uses APIC id 0. Add the missing implementation of arch_match_cpu_phys_id() so that CPU-node lookups work also with SMP. Apart from fixing the broken sysfs devicetree-node links this likely does not affect current users of mainline kernels on x86. Fixes: 4e07db9c8db8 ("x86/devicetree: Use CPU description from Device Tree") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210312092033.26317-1-johan@kernel.org
2021-03-19Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm fixes from Paolo Bonzini: "Fixes for kvm on x86: - new selftests - fixes for migration with HyperV re-enlightenment enabled - fix RCU/SRCU usage - fixes for local_irq_restore misuse false positive" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: documentation/kvm: additional explanations on KVM_SET_BOOT_CPU_ID x86/kvm: Fix broken irq restoration in kvm_wait KVM: X86: Fix missing local pCPU when executing wbinvd on all dirty pCPUs KVM: x86: Protect userspace MSR filter with SRCU, and set atomically-ish selftests: kvm: add set_boot_cpu_id test selftests: kvm: add _vm_ioctl selftests: kvm: add get_msr_index_features selftests: kvm: Add basic Hyper-V clocksources tests KVM: x86: hyper-v: Don't touch TSC page values when guest opted for re-enlightenment KVM: x86: hyper-v: Track Hyper-V TSC page status KVM: x86: hyper-v: Prevent using not-yet-updated TSC page by secondary CPUs KVM: x86: hyper-v: Limit guest to writing zero to HV_X64_MSR_TSC_EMULATION_STATUS KVM: x86/mmu: Store the address space ID in the TDP iterator KVM: x86/mmu: Factor out tdp_iter_return_to_root KVM: x86/mmu: Fix RCU usage when atomically zapping SPTEs KVM: x86/mmu: Fix RCU usage in handle_removed_tdp_mmu_page
2021-03-19x86/ioapic: Ignore IRQ2 againThomas Gleixner
Vitaly ran into an issue with hotplugging CPU0 on an Amazon instance where the matrix allocator claimed to be out of vectors. He analyzed it down to the point that IRQ2, the PIC cascade interrupt, which is supposed to be not ever routed to the IO/APIC ended up having an interrupt vector assigned which got moved during unplug of CPU0. The underlying issue is that IRQ2 for various reasons (see commit af174783b925 ("x86: I/O APIC: Never configure IRQ2" for details) is treated as a reserved system vector by the vector core code and is not accounted as a regular vector. The Amazon BIOS has an routing entry of pin2 to IRQ2 which causes the IO/APIC setup to claim that interrupt which is granted by the vector domain because there is no sanity check. As a consequence the allocation counter of CPU0 underflows which causes a subsequent unplug to fail with: [ ... ] CPU 0 has 4294967295 vectors, 589 available. Cannot disable CPU There is another sanity check missing in the matrix allocator, but the underlying root cause is that the IO/APIC code lost the IRQ2 ignore logic during the conversion to irqdomains. For almost 6 years nobody complained about this wreckage, which might indicate that this requirement could be lifted, but for any system which actually has a PIC IRQ2 is unusable by design so any routing entry has no effect and the interrupt cannot be connected to a device anyway. Due to that and due to history biased paranoia reasons restore the IRQ2 ignore logic and treat it as non existent despite a routing entry claiming otherwise. Fixes: d32932d02e18 ("x86/irq: Convert IOAPIC to use hierarchical irqdomain interfaces") Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210318192819.636943062@linutronix.de
2021-03-18x86/kvm: Fix broken irq restoration in kvm_waitWanpeng Li
After commit 997acaf6b4b59c (lockdep: report broken irq restoration), the guest splatting below during boot: raw_local_irq_restore() called with IRQs enabled WARNING: CPU: 1 PID: 169 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x26/0x30 Modules linked in: hid_generic usbhid hid CPU: 1 PID: 169 Comm: systemd-udevd Not tainted 5.11.0+ #25 RIP: 0010:warn_bogus_irq_restore+0x26/0x30 Call Trace: kvm_wait+0x76/0x90 __pv_queued_spin_lock_slowpath+0x285/0x2e0 do_raw_spin_lock+0xc9/0xd0 _raw_spin_lock+0x59/0x70 lockref_get_not_dead+0xf/0x50 __legitimize_path+0x31/0x60 legitimize_root+0x37/0x50 try_to_unlazy_next+0x7f/0x1d0 lookup_fast+0xb0/0x170 path_openat+0x165/0x9b0 do_filp_open+0x99/0x110 do_sys_openat2+0x1f1/0x2e0 do_sys_open+0x5c/0x80 __x64_sys_open+0x21/0x30 do_syscall_64+0x32/0x50 entry_SYSCALL_64_after_hwframe+0x44/0xae The new consistency checking, expects local_irq_save() and local_irq_restore() to be paired and sanely nested, and therefore expects local_irq_restore() to be called with irqs disabled. The irqflags handling in kvm_wait() which ends up doing: local_irq_save(flags); safe_halt(); local_irq_restore(flags); instead triggers it. This patch fixes it by using local_irq_disable()/enable() directly. Cc: Thomas Gleixner <tglx@linutronix.de> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Message-Id: <1615791328-2735-1-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-18KVM: X86: Fix missing local pCPU when executing wbinvd on all dirty pCPUsWanpeng Li
In order to deal with noncoherent DMA, we should execute wbinvd on all dirty pCPUs when guest wbinvd exits to maintain data consistency. smp_call_function_many() does not execute the provided function on the local core, therefore replace it by on_each_cpu_mask(). Reported-by: Nadav Amit <namit@vmware.com> Cc: Nadav Amit <namit@vmware.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Message-Id: <1615517151-7465-1-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-18KVM: x86: Protect userspace MSR filter with SRCU, and set atomically-ishSean Christopherson
Fix a plethora of issues with MSR filtering by installing the resulting filter as an atomic bundle instead of updating the live filter one range at a time. The KVM_X86_SET_MSR_FILTER ioctl() isn't truly atomic, as the hardware MSR bitmaps won't be updated until the next VM-Enter, but the relevant software struct is atomically updated, which is what KVM really needs. Similar to the approach used for modifying memslots, make arch.msr_filter a SRCU-protected pointer, do all the work configuring the new filter outside of kvm->lock, and then acquire kvm->lock only when the new filter has been vetted and created. That way vCPU readers either see the old filter or the new filter in their entirety, not some half-baked state. Yuan Yao pointed out a use-after-free in ksm_msr_allowed() due to a TOCTOU bug, but that's just the tip of the iceberg... - Nothing is __rcu annotated, making it nigh impossible to audit the code for correctness. - kvm_add_msr_filter() has an unpaired smp_wmb(). Violation of kernel coding style aside, the lack of a smb_rmb() anywhere casts all code into doubt. - kvm_clear_msr_filter() has a double free TOCTOU bug, as it grabs count before taking the lock. - kvm_clear_msr_filter() also has memory leak due to the same TOCTOU bug. The entire approach of updating the live filter is also flawed. While installing a new filter is inherently racy if vCPUs are running, fixing the above issues also makes it trivial to ensure certain behavior is deterministic, e.g. KVM can provide deterministic behavior for MSRs with identical settings in the old and new filters. An atomic update of the filter also prevents KVM from getting into a half-baked state, e.g. if installing a filter fails, the existing approach would leave the filter in a half-baked state, having already committed whatever bits of the filter were already processed. [*] https://lkml.kernel.org/r/20210312083157.25403-1-yaoyuan0329os@gmail.com Fixes: 1a155254ff93 ("KVM: x86: Introduce MSR filtering") Cc: stable@vger.kernel.org Cc: Alexander Graf <graf@amazon.com> Reported-by: Yuan Yao <yaoyuan0329os@gmail.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210316184436.2544875-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-18KVM: x86: hyper-v: Don't touch TSC page values when guest opted for ↵Vitaly Kuznetsov
re-enlightenment When guest opts for re-enlightenment notifications upon migration, it is in its right to assume that TSC page values never change (as they're only supposed to change upon migration and the host has to keep things as they are before it receives confirmation from the guest). This is mostly true until the guest is migrated somewhere. KVM userspace (e.g. QEMU) will trigger masterclock update by writing to HV_X64_MSR_REFERENCE_TSC, by calling KVM_SET_CLOCK,... and as TSC value and kvmclock reading drift apart (even slightly), the update causes TSC page values to change. The issue at hand is that when Hyper-V is migrated, it uses stale (cached) TSC page values to compute the difference between its own clocksource (provided by KVM) and its guests' TSC pages to program synthetic timers and in some cases, when TSC page is updated, this puts all stimer expirations in the past. This, in its turn, causes an interrupt storm and L2 guests not making much forward progress. Note, KVM doesn't fully implement re-enlightenment notification. Basically, the support for reenlightenment MSRs is just a stub and userspace is only expected to expose the feature when TSC scaling on the expected destination hosts is available. With TSC scaling, no real re-enlightenment is needed as TSC frequency doesn't change. With TSC scaling becoming ubiquitous, it likely makes little sense to fully implement re-enlightenment in KVM. Prevent TSC page from being updated after migration. In case it's not the guest who's initiating the change and when TSC page is already enabled, just keep it as it is: TSC value is supposed to be preserved across migration and TSC frequency can't change with re-enlightenment enabled. The guest is doomed anyway if any of this is not true. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210316143736.964151-5-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-18KVM: x86: hyper-v: Track Hyper-V TSC page statusVitaly Kuznetsov
Create an infrastructure for tracking Hyper-V TSC page status, i.e. if it was updated from guest/host side or if we've failed to set it up (because e.g. guest wrote some garbage to HV_X64_MSR_REFERENCE_TSC) and there's no need to retry. Also, in a hypothetical situation when we are in 'always catchup' mode for TSC we can now avoid contending 'hv->hv_lock' on every guest enter by setting the state to HV_TSC_PAGE_BROKEN after compute_tsc_page_parameters() returns false. Check for HV_TSC_PAGE_SET state instead of '!hv->tsc_ref.tsc_sequence' in get_time_ref_counter() to properly handle the situation when we failed to write the updated TSC page values to the guest. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210316143736.964151-4-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-18bpf: Fix fexit trampoline.Alexei Starovoitov
The fexit/fmod_ret programs can be attached to kernel functions that can sleep. The synchronize_rcu_tasks() will not wait for such tasks to complete. In such case the trampoline image will be freed and when the task wakes up the return IP will point to freed memory causing the crash. Solve this by adding percpu_ref_get/put for the duration of trampoline and separate trampoline vs its image life times. The "half page" optimization has to be removed, since first_half->second_half->first_half transition cannot be guaranteed to complete in deterministic time. Every trampoline update becomes a new image. The image with fmod_ret or fexit progs will be freed via percpu_ref_kill and call_rcu_tasks. Together they will wait for the original function and trampoline asm to complete. The trampoline is patched from nop to jmp to skip fexit progs. They are freed independently from the trampoline. The image with fentry progs only will be freed via call_rcu_tasks_trace+call_rcu_tasks which will wait for both sleepable and non-sleepable progs to complete. Fixes: fec56f5890d9 ("bpf: Introduce BPF trampoline") Reported-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Paul E. McKenney <paulmck@kernel.org> # for RCU Link: https://lore.kernel.org/bpf/20210316210007.38949-1-alexei.starovoitov@gmail.com
2021-03-17module: remove never implemented MODULE_SUPPORTED_DEVICELeon Romanovsky
MODULE_SUPPORTED_DEVICE was added in pre-git era and never was implemented. We can safely remove it, because the kernel has grown to have many more reliable mechanisms to determine if device is supported or not. Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-17KVM: x86: hyper-v: Prevent using not-yet-updated TSC page by secondary CPUsVitaly Kuznetsov
When KVM_REQ_MASTERCLOCK_UPDATE request is issued (e.g. after migration) we need to make sure no vCPU sees stale values in PV clock structures and thus all vCPUs are kicked with KVM_REQ_CLOCK_UPDATE. Hyper-V TSC page clocksource is global and kvm_guest_time_update() only updates in on vCPU0 but this is not entirely correct: nothing blocks some other vCPU from entering the guest before we finish the update on CPU0 and it can read stale values from the page. Invalidate TSC page in kvm_gen_update_masterclock() to switch all vCPUs to using MSR based clocksource (HV_X64_MSR_TIME_REF_COUNT). Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210316143736.964151-3-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-17KVM: x86: hyper-v: Limit guest to writing zero to ↵Vitaly Kuznetsov
HV_X64_MSR_TSC_EMULATION_STATUS HV_X64_MSR_TSC_EMULATION_STATUS indicates whether TSC accesses are emulated after migration (to accommodate for a different host TSC frequency when TSC scaling is not supported; we don't implement this in KVM). Guest can use the same MSR to stop TSC access emulation by writing zero. Writing anything else is forbidden. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210316143736.964151-2-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-16ftrace: Fix spelling mistake "disabed" -> "disabled"Colin Ian King
There is a spelling mistake in a comment, fix it. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-16x86: Introduce restart_block->arch_data to remove TS_COMPAT_RESTARTOleg Nesterov
Save the current_thread_info()->status of X86 in the new restart_block->arch_data field so TS_COMPAT_RESTART can be removed again. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210201174716.GA17898@redhat.com
2021-03-16x86: Introduce TS_COMPAT_RESTART to fix get_nr_restart_syscall()Oleg Nesterov
The comment in get_nr_restart_syscall() says: * The problem is that we can get here when ptrace pokes * syscall-like values into regs even if we're not in a syscall * at all. Yes, but if not in a syscall then the status & (TS_COMPAT|TS_I386_REGS_POKED) check below can't really help: - TS_COMPAT can't be set - TS_I386_REGS_POKED is only set if regs->orig_ax was changed by 32bit debugger; and even in this case get_nr_restart_syscall() is only correct if the tracee is 32bit too. Suppose that a 64bit debugger plays with a 32bit tracee and * Tracee calls sleep(2) // TS_COMPAT is set * User interrupts the tracee by CTRL-C after 1 sec and does "(gdb) call func()" * gdb saves the regs by PTRACE_GETREGS * does PTRACE_SETREGS to set %rip='func' and %orig_rax=-1 * PTRACE_CONT // TS_COMPAT is cleared * func() hits int3. * Debugger catches SIGTRAP. * Restore original regs by PTRACE_SETREGS. * PTRACE_CONT get_nr_restart_syscall() wrongly returns __NR_restart_syscall==219, the tracee calls ia32_sys_call_table[219] == sys_madvise. Add the sticky TS_COMPAT_RESTART flag which survives after return to user mode. It's going to be removed in the next step again by storing the information in the restart block. As a further cleanup it might be possible to remove also TS_I386_REGS_POKED with that. Test-case: $ cvs -d :pserver:anoncvs:anoncvs@sourceware.org:/cvs/systemtap co ptrace-tests $ gcc -o erestartsys-trap-debuggee ptrace-tests/tests/erestartsys-trap-debuggee.c --m32 $ gcc -o erestartsys-trap-debugger ptrace-tests/tests/erestartsys-trap-debugger.c -lutil $ ./erestartsys-trap-debugger Unexpected: retval 1, errno 22 erestartsys-trap-debugger: ptrace-tests/tests/erestartsys-trap-debugger.c:421 Fixes: 609c19a385c8 ("x86/ptrace: Stop setting TS_COMPAT in ptrace code") Reported-by: Jan Kratochvil <jan.kratochvil@redhat.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210201174709.GA17895@redhat.com
2021-03-16x86: Move TS_COMPAT back to asm/thread_info.hOleg Nesterov
Move TS_COMPAT back to asm/thread_info.h, close to TS_I386_REGS_POKED. It was moved to asm/processor.h by b9d989c7218a ("x86/asm: Move the thread_info::status field to thread_struct"), then later 37a8f7c38339 ("x86/asm: Move 'status' from thread_struct to thread_info") moved the 'status' field back but TS_COMPAT was forgotten. Preparatory patch to fix the COMPAT case for get_nr_restart_syscall() Fixes: 609c19a385c8 ("x86/ptrace: Stop setting TS_COMPAT in ptrace code") Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210201174649.GA17880@redhat.com
2021-03-16perf/x86/intel: Fix unchecked MSR access error caused by VLBR_EVENTKan Liang
On a Haswell machine, the perf_fuzzer managed to trigger this message: [117248.075892] unchecked MSR access error: WRMSR to 0x3f1 (tried to write 0x0400000000000000) at rIP: 0xffffffff8106e4f4 (native_write_msr+0x4/0x20) [117248.089957] Call Trace: [117248.092685] intel_pmu_pebs_enable_all+0x31/0x40 [117248.097737] intel_pmu_enable_all+0xa/0x10 [117248.102210] __perf_event_task_sched_in+0x2df/0x2f0 [117248.107511] finish_task_switch.isra.0+0x15f/0x280 [117248.112765] schedule_tail+0xc/0x40 [117248.116562] ret_from_fork+0x8/0x30 A fake event called VLBR_EVENT may use the bit 58 of the PEBS_ENABLE, if the precise_ip is set. The bit 58 is reserved by the HW. Accessing the bit causes the unchecked MSR access error. The fake event doesn't support PEBS. The case should be rejected. Fixes: 097e4311cda9 ("perf/x86: Add constraint to create guest LBR event without hw counter") Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1615555298-140216-2-git-send-email-kan.liang@linux.intel.com
2021-03-16perf/x86/intel: Fix a crash caused by zero PEBS statusKan Liang
A repeatable crash can be triggered by the perf_fuzzer on some Haswell system. https://lore.kernel.org/lkml/7170d3b-c17f-1ded-52aa-cc6d9ae999f4@maine.edu/ For some old CPUs (HSW and earlier), the PEBS status in a PEBS record may be mistakenly set to 0. To minimize the impact of the defect, the commit was introduced to try to avoid dropping the PEBS record for some cases. It adds a check in the intel_pmu_drain_pebs_nhm(), and updates the local pebs_status accordingly. However, it doesn't correct the PEBS status in the PEBS record, which may trigger the crash, especially for the large PEBS. It's possible that all the PEBS records in a large PEBS have the PEBS status 0. If so, the first get_next_pebs_record_by_bit() in the __intel_pmu_pebs_event() returns NULL. The at = NULL. Since it's a large PEBS, the 'count' parameter must > 1. The second get_next_pebs_record_by_bit() will crash. Besides the local pebs_status, correct the PEBS status in the PEBS record as well. Fixes: 01330d7288e0 ("perf/x86: Allow zero PEBS status with only single active event") Reported-by: Vince Weaver <vincent.weaver@maine.edu> Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1615555298-140216-1-git-send-email-kan.liang@linux.intel.com
2021-03-16KVM: x86/mmu: Store the address space ID in the TDP iteratorSean Christopherson
Store the address space ID in the TDP iterator so that it can be retrieved without having to bounce through the root shadow page. This streamlines the code and fixes a Sparse warning about not properly using rcu_dereference() when grabbing the ID from the root on the fly. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20210315233803.2706477-5-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>