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* xen: remove trailing semicolon in macro definitionTom Rix2020-12-161-1/+1
| | | | | | | | | The macro use will already have a semicolon. Signed-off-by: Tom Rix <trix@redhat.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20201127160707.2622061-1-trix@redhat.com Signed-off-by: Juergen Gross <jgross@suse.com>
* xen: Kconfig: nest Xen guest optionsJason Andryuk2020-12-161-13/+13
| | | | | | | | | | | | | | | | | Moving XEN_512GB allows it to nest under XEN_PV. That also allows XEN_PVH to nest under XEN as a sibling to XEN_PV and XEN_PVHVM giving: [*] Xen guest support [*] Xen PV guest support [*] Limit Xen pv-domain memory to 512GB [*] Xen PV Dom0 support [*] Xen PVHVM guest support [*] Xen PVH guest support Signed-off-by: Jason Andryuk <jandryuk@gmail.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20201014175342.152712-3-jandryuk@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
* xen: Remove Xen PVH/PVHVM dependency on PCIJason Andryuk2020-12-161-6/+12
| | | | | | | | | | | | | | | | | | A Xen PVH domain doesn't have a PCI bus or devices, so it doesn't need PCI support built in. Currently, XEN_PVH depends on XEN_PVHVM which depends on PCI. Introduce XEN_PVHVM_GUEST as a toplevel item and change XEN_PVHVM to a hidden variable. This allows XEN_PVH to depend on XEN_PVHVM without PCI while XEN_PVHVM_GUEST depends on PCI. In drivers/xen, compile platform-pci depending on XEN_PVHVM_GUEST since that pulls in the PCI dependency for linking. Signed-off-by: Jason Andryuk <jandryuk@gmail.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20201014175342.152712-2-jandryuk@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
* x86/xen: Convert to DEFINE_SHOW_ATTRIBUTEQinglang Miao2020-12-161-11/+1
| | | | | | | | | Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code. Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20200917125547.104472-1-miaoqinglang@huawei.com Signed-off-by: Juergen Gross <jgross@suse.com>
* Merge tag 'x86-urgent-2020-12-13' of ↵Linus Torvalds2020-12-137-24/+52
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A set of x86 and membarrier fixes: - Correct a few problems in the x86 and the generic membarrier implementation. Small corrections for assumptions about visibility which have turned out not to be true. - Make the PAT bits for memory encryption correct vs 4K and 2M/1G page table entries as they are at a different location. - Fix a concurrency issue in the the local bandwidth readout of resource control leading to incorrect values - Fix the ordering of allocating a vector for an interrupt. The order missed to respect the provided cpumask when the first attempt of allocating node local in the mask fails. It then tries the node instead of trying the full provided mask first. This leads to erroneous error messages and breaking the (user) supplied affinity request. Reorder it. - Make the INT3 padding detection in optprobe work correctly" * tag 'x86-urgent-2020-12-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/kprobes: Fix optprobe to detect INT3 padding correctly x86/apic/vector: Fix ordering in vector assignment x86/resctrl: Fix incorrect local bandwidth when mba_sc is enabled x86/mm/mem_encrypt: Fix definition of PMD_FLAGS_DEC_WP membarrier: Execute SYNC_CORE on the calling thread membarrier: Explicitly sync remote cores when SYNC_CORE is requested membarrier: Add an actual barrier before rseq_preempt() x86/membarrier: Get rid of a dubious optimization
| * x86/kprobes: Fix optprobe to detect INT3 padding correctlyMasami Hiramatsu2020-12-121-2/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 7705dc855797 ("x86/vmlinux: Use INT3 instead of NOP for linker fill bytes") changed the padding bytes between functions from NOP to INT3. However, when optprobe decodes a target function it finds INT3 and gives up the jump optimization. Instead of giving up any INT3 detection, check whether the rest of the bytes to the end of the function are INT3. If all of them are INT3, those come from the linker. In that case, continue the optprobe jump optimization. [ bp: Massage commit message. ] Fixes: 7705dc855797 ("x86/vmlinux: Use INT3 instead of NOP for linker fill bytes") Reported-by: Adam Zabrocki <pi3@pi3.com.pl> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/160767025681.3880685.16021570341428835411.stgit@devnote2
| * x86/apic/vector: Fix ordering in vector assignmentThomas Gleixner2020-12-101-10/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Prarit reported that depending on the affinity setting the ' irq $N: Affinity broken due to vector space exhaustion.' message is showing up in dmesg, but the vector space on the CPUs in the affinity mask is definitely not exhausted. Shung-Hsi provided traces and analysis which pinpoints the problem: The ordering of trying to assign an interrupt vector in assign_irq_vector_any_locked() is simply wrong if the interrupt data has a valid node assigned. It does: 1) Try the intersection of affinity mask and node mask 2) Try the node mask 3) Try the full affinity mask 4) Try the full online mask Obviously #2 and #3 are in the wrong order as the requested affinity mask has to take precedence. In the observed cases #1 failed because the affinity mask did not contain CPUs from node 0. That made it allocate a vector from node 0, thereby breaking affinity and emitting the misleading message. Revert the order of #2 and #3 so the full affinity mask without the node intersection is tried before actually affinity is broken. If no node is assigned then only the full affinity mask and if that fails the full online mask is tried. Fixes: d6ffc6ac83b1 ("x86/vector: Respect affinity mask in irq descriptor") Reported-by: Prarit Bhargava <prarit@redhat.com> Reported-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/87ft4djtyp.fsf@nanos.tec.linutronix.de
| * x86/resctrl: Fix incorrect local bandwidth when mba_sc is enabledXiaochen Shen2020-12-101-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The MBA software controller (mba_sc) is a feedback loop which periodically reads MBM counters and tries to restrict the bandwidth below a user-specified value. It tags along the MBM counter overflow handler to do the updates with 1s interval in mbm_update() and update_mba_bw(). The purpose of mbm_update() is to periodically read the MBM counters to make sure that the hardware counter doesn't wrap around more than once between user samplings. mbm_update() calls __mon_event_count() for local bandwidth updating when mba_sc is not enabled, but calls mbm_bw_count() instead when mba_sc is enabled. __mon_event_count() will not be called for local bandwidth updating in MBM counter overflow handler, but it is still called when reading MBM local bandwidth counter file 'mbm_local_bytes', the call path is as below: rdtgroup_mondata_show() mon_event_read() mon_event_count() __mon_event_count() In __mon_event_count(), m->chunks is updated by delta chunks which is calculated from previous MSR value (m->prev_msr) and current MSR value. When mba_sc is enabled, m->chunks is also updated in mbm_update() by mistake by the delta chunks which is calculated from m->prev_bw_msr instead of m->prev_msr. But m->chunks is not used in update_mba_bw() in the mba_sc feedback loop. When reading MBM local bandwidth counter file, m->chunks was changed unexpectedly by mbm_bw_count(). As a result, the incorrect local bandwidth counter which calculated from incorrect m->chunks is shown to the user. Fix this by removing incorrect m->chunks updating in mbm_bw_count() in MBM counter overflow handler, and always calling __mon_event_count() in mbm_update() to make sure that the hardware local bandwidth counter doesn't wrap around. Test steps: # Run workload with aggressive memory bandwidth (e.g., 10 GB/s) git clone https://github.com/intel/intel-cmt-cat && cd intel-cmt-cat && make ./tools/membw/membw -c 0 -b 10000 --read # Enable MBA software controller mount -t resctrl resctrl -o mba_MBps /sys/fs/resctrl # Create control group c1 mkdir /sys/fs/resctrl/c1 # Set MB throttle to 6 GB/s echo "MB:0=6000;1=6000" > /sys/fs/resctrl/c1/schemata # Write PID of the workload to tasks file echo `pidof membw` > /sys/fs/resctrl/c1/tasks # Read local bytes counters twice with 1s interval, the calculated # local bandwidth is not as expected (approaching to 6 GB/s): local_1=`cat /sys/fs/resctrl/c1/mon_data/mon_L3_00/mbm_local_bytes` sleep 1 local_2=`cat /sys/fs/resctrl/c1/mon_data/mon_L3_00/mbm_local_bytes` echo "local b/w (bytes/s):" `expr $local_2 - $local_1` Before fix: local b/w (bytes/s): 11076796416 After fix: local b/w (bytes/s): 5465014272 Fixes: ba0f26d8529c (x86/intel_rdt/mba_sc: Prepare for feedback loop) Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/1607063279-19437-1-git-send-email-xiaochen.shen@intel.com
| * x86/mm/mem_encrypt: Fix definition of PMD_FLAGS_DEC_WPArvind Sankar2020-12-102-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The PAT bit is in different locations for 4k and 2M/1G page table entries. Add a definition for _PAGE_LARGE_CACHE_MASK to represent the three caching bits (PWT, PCD, PAT), similar to _PAGE_CACHE_MASK for 4k pages, and use it in the definition of PMD_FLAGS_DEC_WP to get the correct PAT index for write-protected pages. Fixes: 6ebcb060713f ("x86/mm: Add support to encrypt the kernel in-place") Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20201111160946.147341-1-nivedita@alum.mit.edu
| * x86/membarrier: Get rid of a dubious optimizationAndy Lutomirski2020-12-092-6/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sync_core_before_usermode() had an incorrect optimization. If the kernel returns from an interrupt, it can get to usermode without IRET. It just has to schedule to a different task in the same mm and do SYSRET. Fortunately, there were no callers of sync_core_before_usermode() that could have had in_irq() or in_nmi() equal to true, because it's only ever called from the scheduler. While at it, clarify a related comment. Fixes: 70216e18e519 ("membarrier: Provide core serializing command, *_SYNC_CORE") Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/5afc7632be1422f91eaf7611aaaa1b5b8580a086.1607058304.git.luto@kernel.org
* | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2020-12-124-13/+24
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | Pull kvm fixes from Paolo Bonzini: "Bugfixes for ARM, x86 and tools" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: tools/kvm_stat: Exempt time-based counters KVM: mmu: Fix SPTE encoding of MMIO generation upper half kvm: x86/mmu: Use cpuid to determine max gfn kvm: svm: de-allocate svm_cpu_data for all cpus in svm_cpu_uninit() selftests: kvm/set_memory_region_test: Fix race in move region test KVM: arm64: Add usage of stage 2 fault lookup level in user_mem_abort() KVM: arm64: Fix handling of merging tables into a block entry KVM: arm64: Fix memory leak on stage2 update of a valid PTE
| * KVM: mmu: Fix SPTE encoding of MMIO generation upper halfMaciej S. Szmigiero2020-12-112-9/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit cae7ed3c2cb0 ("KVM: x86: Refactor the MMIO SPTE generation handling") cleaned up the computation of MMIO generation SPTE masks, however it introduced a bug how the upper part was encoded: SPTE bits 52-61 were supposed to contain bits 10-19 of the current generation number, however a missing shift encoded bits 1-10 there instead (mostly duplicating the lower part of the encoded generation number that then consisted of bits 1-9). In the meantime, the upper part was shrunk by one bit and moved by subsequent commits to become an upper half of the encoded generation number (bits 9-17 of bits 0-17 encoded in a SPTE). In addition to the above, commit 56871d444bc4 ("KVM: x86: fix overlap between SPTE_MMIO_MASK and generation") has changed the SPTE bit range assigned to encode the generation number and the total number of bits encoded but did not update them in the comment attached to their defines, nor in the KVM MMU doc. Let's do it here, too, since it is too trivial thing to warrant a separate commit. Fixes: cae7ed3c2cb0 ("KVM: x86: Refactor the MMIO SPTE generation handling") Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Message-Id: <156700708db2a5296c5ed7a8b9ac71f1e9765c85.1607129096.git.maciej.szmigiero@oracle.com> Cc: stable@vger.kernel.org [Reorganize macros so that everything is computed from the bit ranges. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * kvm: x86/mmu: Use cpuid to determine max gfnRick Edgecombe2020-12-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the TDP MMU, use shadow_phys_bits to dermine the maximum possible GFN mapped in the guest for zapping operations. boot_cpu_data.x86_phys_bits may be reduced in the case of HW features that steal HPA bits for other purposes. However, this doesn't necessarily reduce GPA space that can be accessed via TDP. So zap based on a maximum gfn calculated with MAXPHYADDR retrieved from CPUID. This is already stored in shadow_phys_bits, so use it instead of x86_phys_bits. Fixes: faaf05b00aec ("kvm: x86/mmu: Support zapping SPTEs in the TDP MMU") Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Message-Id: <20201203231120.27307-1-rick.p.edgecombe@intel.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * kvm: svm: de-allocate svm_cpu_data for all cpus in svm_cpu_uninit()Jacob Xu2020-12-041-2/+2
| | | | | | | | | | | | | | | | | | The cpu arg for svm_cpu_uninit() was previously ignored resulting in the per cpu structure svm_cpu_data not being de-allocated for all cpus. Signed-off-by: Jacob Xu <jacobhxu@google.com> Message-Id: <20201203205939.1783969-1-jacobhxu@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | Merge tag 'x86-urgent-2020-12-06' of ↵Linus Torvalds2020-12-068-15/+43
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A set of fixes for x86: - Make the AMD L3 QoS code and data priorization enable/disable mechanism work correctly. The control bit was only set/cleared on one of the CPUs in a L3 domain, but it has to be modified on all CPUs in the domain. The initial documentation was not clear about this, but the updated one from Oct 2020 spells it out. - Fix an off by one in the UV platform detection code which causes the UV hubs to be identified wrongly. The chip revisions start at 1 not at 0. - Fix a long standing bug in the evaluation of prefixes in the uprobes code which fails to handle repeated prefixes properly. The aggregate size of the prefixes can be larger than the bytes array but the code blindly iterated over the aggregate size beyond the array boundary. Add a macro to handle this case properly and use it at the affected places" * tag 'x86-urgent-2020-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/sev-es: Use new for_each_insn_prefix() macro to loop over prefixes bytes x86/insn-eval: Use new for_each_insn_prefix() macro to loop over prefixes bytes x86/uprobes: Do not use prefixes.nbytes when looping over prefixes.bytes x86/platform/uv: Fix UV4 hub revision adjustment x86/resctrl: Fix AMD L3 QOS CDP enable/disable
| * | x86/sev-es: Use new for_each_insn_prefix() macro to loop over prefixes bytesMasami Hiramatsu2020-12-061-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since insn.prefixes.nbytes can be bigger than the size of insn.prefixes.bytes[] when a prefix is repeated, the proper check must be: insn.prefixes.bytes[i] != 0 and i < 4 instead of using insn.prefixes.nbytes. Use the new for_each_insn_prefix() macro which does it correctly. Debugged by Kees Cook <keescook@chromium.org>. [ bp: Massage commit message. ] Fixes: 25189d08e516 ("x86/sev-es: Add support for handling IOIO exceptions") Reported-by: syzbot+9b64b619f10f19d19a7c@syzkaller.appspotmail.com Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/160697106089.3146288.2052422845039649176.stgit@devnote2
| * | x86/insn-eval: Use new for_each_insn_prefix() macro to loop over prefixes bytesMasami Hiramatsu2020-12-061-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since insn.prefixes.nbytes can be bigger than the size of insn.prefixes.bytes[] when a prefix is repeated, the proper check must be insn.prefixes.bytes[i] != 0 and i < 4 instead of using insn.prefixes.nbytes. Use the new for_each_insn_prefix() macro which does it correctly. Debugged by Kees Cook <keescook@chromium.org>. [ bp: Massage commit message. ] Fixes: 32d0b95300db ("x86/insn-eval: Add utility functions to get segment selector") Reported-by: syzbot+9b64b619f10f19d19a7c@syzkaller.appspotmail.com Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/160697104969.3146288.16329307586428270032.stgit@devnote2
| * | x86/uprobes: Do not use prefixes.nbytes when looping over prefixes.bytesMasami Hiramatsu2020-12-062-4/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since insn.prefixes.nbytes can be bigger than the size of insn.prefixes.bytes[] when a prefix is repeated, the proper check must be insn.prefixes.bytes[i] != 0 and i < 4 instead of using insn.prefixes.nbytes. Introduce a for_each_insn_prefix() macro for this purpose. Debugged by Kees Cook <keescook@chromium.org>. [ bp: Massage commit message, sync with the respective header in tools/ and drop "we". ] Fixes: 2b1444983508 ("uprobes, mm, x86: Add the ability to install and remove uprobes breakpoints") Reported-by: syzbot+9b64b619f10f19d19a7c@syzkaller.appspotmail.com Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/160697103739.3146288.7437620795200799020.stgit@devnote2
| * | x86/platform/uv: Fix UV4 hub revision adjustmentMike Travis2020-12-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, UV4 is incorrectly identified as UV4A and UV4A as UV5. Hub chip starts with revision 1, fix it. [ bp: Massage commit message. ] Fixes: 647128f1536e ("x86/platform/uv: Update UV MMRs for UV5") Signed-off-by: Mike Travis <mike.travis@hpe.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Steve Wahl <steve.wahl@hpe.com> Acked-by: Dimitri Sivanich <dimitri.sivanich@hpe.com> Link: https://lkml.kernel.org/r/20201203152252.371199-1-mike.travis@hpe.com
| * | x86/resctrl: Fix AMD L3 QOS CDP enable/disableBabu Moger2020-12-013-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the AMD QoS feature CDP (code and data prioritization) is enabled or disabled, the CDP bit in MSR 0000_0C81 is written on one of the CPUs in an L3 domain (core complex). That is not correct - the CDP bit needs to be updated on all the logical CPUs in the domain. This was not spelled out clearly in the spec earlier. The specification has been updated and the updated document, "AMD64 Technology Platform Quality of Service Extensions Publication # 56375 Revision: 1.02 Issue Date: October 2020" is available now. Refer the section: Code and Data Prioritization. Fix the issue by adding a new flag arch_has_per_cpu_cfg in rdt_cache data structure. The documentation can be obtained at: https://developer.amd.com/wp-content/resources/56375.pdf Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 [ bp: Massage commit message. ] Fixes: 4d05bf71f157 ("x86/resctrl: Introduce AMD QOS feature") Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/160675180380.15628.3309402017215002347.stgit@bmoger-ubuntu
* | | Merge tag 'perf-urgent-2020-12-06' of ↵Linus Torvalds2020-12-061-2/+2
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "Two fixes for performance monitoring on X86: - Add recursion protection to another callchain invoked from x86_pmu_stop() which can recurse back into x86_pmu_stop(). The first attempt to fix this missed this extra code path. - Use the already filtered status variable to check for PEBS counter overflow bits and not the unfiltered full status read from IA32_PERF_GLOBAL_STATUS which can have unrelated bits check which would be evaluated incorrectly" * tag 'perf-urgent-2020-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel: Check PEBS status correctly perf/x86/intel: Fix a warning on x86_pmu_stop() with large PEBS
| * | | perf/x86/intel: Check PEBS status correctlyStephane Eranian2020-12-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel cannot disambiguate when 2+ PEBS counters overflow at the same time. This is what the comment for this code suggests. However, I see the comparison is done with the unfiltered p->status which is a copy of IA32_PERF_GLOBAL_STATUS at the time of the sample. This register contains more than the PEBS counter overflow bits. It also includes many other bits which could also be set. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20201126110922.317681-2-namhyung@kernel.org
| * | | perf/x86/intel: Fix a warning on x86_pmu_stop() with large PEBSNamhyung Kim2020-12-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The commit 3966c3feca3f ("x86/perf/amd: Remove need to check "running" bit in NMI handler") introduced this. It seems x86_pmu_stop can be called recursively (like when it losts some samples) like below: x86_pmu_stop intel_pmu_disable_event (x86_pmu_disable) intel_pmu_pebs_disable intel_pmu_drain_pebs_nhm (x86_pmu_drain_pebs_buffer) x86_pmu_stop While commit 35d1ce6bec13 ("perf/x86/intel/ds: Fix x86_pmu_stop warning for large PEBS") fixed it for the normal cases, there's another path to call x86_pmu_stop() recursively when a PEBS error was detected (like two or more counters overflowed at the same time). Like in the Kan's previous fix, we can skip the interrupt accounting for large PEBS, so check the iregs which is set for PMI only. Fixes: 3966c3feca3f ("x86/perf/amd: Remove need to check "running" bit in NMI handler") Reported-by: John Sperbeck <jsperbeck@google.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20201126110922.317681-1-namhyung@kernel.org
* | | | Merge tag 'kbuild-fixes-v5.10-2' of ↵Linus Torvalds2020-12-063-4/+4
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild fixes from Masahiro Yamada: - Move -Wcast-align to W=3, which tends to be false-positive and there is no tree-wide solution. - Pass -fmacro-prefix-map to KBUILD_CPPFLAGS because it is a preprocessor option and makes sense for .S files as well. - Disable -gdwarf-2 for Clang's integrated assembler to avoid warnings. - Disable --orphan-handling=warn for LLD 10.0.1 to avoid warnings. - Fix undesirable line breaks in *.mod files. * tag 'kbuild-fixes-v5.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: avoid split lines in .mod files kbuild: Disable CONFIG_LD_ORPHAN_WARN for ld.lld 10.0.1 kbuild: Hoist '--orphan-handling' into Kconfig Kbuild: do not emit debug info for assembly with LLVM_IAS=1 kbuild: use -fmacro-prefix-map for .S sources Makefile.extrawarn: move -Wcast-align to W=3
| * | | | kbuild: Hoist '--orphan-handling' into KconfigNathan Chancellor2020-12-013-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, '--orphan-handling=warn' is spread out across four different architectures in their respective Makefiles, which makes it a little unruly to deal with in case it needs to be disabled for a specific linker version (in this case, ld.lld 10.0.1). To make it easier to control this, hoist this warning into Kconfig and the main Makefile so that disabling it is simpler, as the warning will only be enabled in a couple places (main Makefile and a couple of compressed boot folders that blow away LDFLAGS_vmlinx) and making it conditional is easier due to Kconfig syntax. One small additional benefit of this is saving a call to ld-option on incremental builds because we will have already evaluated it for CONFIG_LD_ORPHAN_WARN. To keep the list of supported architectures the same, introduce CONFIG_ARCH_WANT_LD_ORPHAN_WARN, which an architecture can select to gain this automatically after all of the sections are specified and size asserted. A special thanks to Kees Cook for the help text on this config. Link: https://github.com/ClangBuiltLinux/linux/issues/1187 Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* | | | | Merge tag 'locking-urgent-2020-11-29' of ↵Linus Torvalds2020-11-292-7/+7
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Thomas Gleixner: "Two more places which invoke tracing from RCU disabled regions in the idle path. Similar to the entry path the low level idle functions have to be non-instrumentable" * tag 'locking-urgent-2020-11-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: intel_idle: Fix intel_idle() vs tracing sched/idle: Fix arch_cpu_idle() vs tracing
| * | | | | sched/idle: Fix arch_cpu_idle() vs tracingPeter Zijlstra2020-11-242-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We call arch_cpu_idle() with RCU disabled, but then use local_irq_{en,dis}able(), which invokes tracing, which relies on RCU. Switch all arch_cpu_idle() implementations to use raw_local_irq_{en,dis}able() and carefully manage the lockdep,rcu,tracing state like we do in entry. (XXX: we really should change arch_cpu_idle() to not return with interrupts enabled) Reported-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
* | | | | | Merge tag 'x86_urgent_for_v5.10-rc6' of ↵Linus Torvalds2020-11-293-43/+32
|\ \ \ \ \ \ | | |_|_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: "A couple of urgent fixes which accumulated this last week: - Two resctrl fixes to prevent refcount leaks when manipulating the resctrl fs (Xiaochen Shen) - Correct prctl(PR_GET_SPECULATION_CTRL) reporting (Anand K Mistry) - A fix to not lose already seen MCE severity which determines whether the machine can recover (Gabriele Paoloni)" * tag 'x86_urgent_for_v5.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Do not overwrite no_way_out if mce_end() fails x86/speculation: Fix prctl() when spectre_v2_user={seccomp,prctl},ibpb x86/resctrl: Add necessary kernfs_put() calls to prevent refcount leak x86/resctrl: Remove superfluous kernfs_get() calls to prevent refcount leak
| * | | | | x86/mce: Do not overwrite no_way_out if mce_end() failsGabriele Paoloni2020-11-271-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, if mce_end() fails, no_way_out - the variable denoting whether the machine can recover from this MCE - is determined by whether the worst severity that was found across the MCA banks associated with the current CPU, is of panic severity. However, at this point no_way_out could have been already set by mca_start() after looking at all severities of all CPUs that entered the MCE handler. If mce_end() fails, check first if no_way_out is already set and, if so, stick to it, otherwise use the local worst value. [ bp: Massage. ] Signed-off-by: Gabriele Paoloni <gabriele.paoloni@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20201127161819.3106432-2-gabriele.paoloni@intel.com
| * | | | | x86/speculation: Fix prctl() when spectre_v2_user={seccomp,prctl},ibpbAnand K Mistry2020-11-251-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When spectre_v2_user={seccomp,prctl},ibpb is specified on the command line, IBPB is force-enabled and STIPB is conditionally-enabled (or not available). However, since 21998a351512 ("x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.") the spectre_v2_user_ibpb variable is set to SPECTRE_V2_USER_{PRCTL,SECCOMP} instead of SPECTRE_V2_USER_STRICT, which is the actual behaviour. Because the issuing of IBPB relies on the switch_mm_*_ibpb static branches, the mitigations behave as expected. Since 1978b3a53a74 ("x86/speculation: Allow IBPB to be conditionally enabled on CPUs with always-on STIBP") this discrepency caused the misreporting of IB speculation via prctl(). On CPUs with STIBP always-on and spectre_v2_user=seccomp,ibpb, prctl(PR_GET_SPECULATION_CTRL) would return PR_SPEC_PRCTL | PR_SPEC_ENABLE instead of PR_SPEC_DISABLE since both IBPB and STIPB are always on. It also allowed prctl(PR_SET_SPECULATION_CTRL) to set the IB speculation mode, even though the flag is ignored. Similarly, for CPUs without SMT, prctl(PR_GET_SPECULATION_CTRL) should also return PR_SPEC_DISABLE since IBPB is always on and STIBP is not available. [ bp: Massage commit message. ] Fixes: 21998a351512 ("x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.") Fixes: 1978b3a53a74 ("x86/speculation: Allow IBPB to be conditionally enabled on CPUs with always-on STIBP") Signed-off-by: Anand K Mistry <amistry@google.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20201110123349.1.Id0cbf996d2151f4c143c90f9028651a5b49a5908@changeid
| * | | | | x86/resctrl: Add necessary kernfs_put() calls to prevent refcount leakXiaochen Shen2020-11-241-7/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On resource group creation via a mkdir an extra kernfs_node reference is obtained by kernfs_get() to ensure that the rdtgroup structure remains accessible for the rdtgroup_kn_unlock() calls where it is removed on deletion. Currently the extra kernfs_node reference count is only dropped by kernfs_put() in rdtgroup_kn_unlock() while the rdtgroup structure is removed in a few other locations that lack the matching reference drop. In call paths of rmdir and umount, when a control group is removed, kernfs_remove() is called to remove the whole kernfs nodes tree of the control group (including the kernfs nodes trees of all child monitoring groups), and then rdtgroup structure is freed by kfree(). The rdtgroup structures of all child monitoring groups under the control group are freed by kfree() in free_all_child_rdtgrp(). Before calling kfree() to free the rdtgroup structures, the kernfs node of the control group itself as well as the kernfs nodes of all child monitoring groups still take the extra references which will never be dropped to 0 and the kernfs nodes will never be freed. It leads to reference count leak and kernfs_node_cache memory leak. For example, reference count leak is observed in these two cases: (1) mount -t resctrl resctrl /sys/fs/resctrl mkdir /sys/fs/resctrl/c1 mkdir /sys/fs/resctrl/c1/mon_groups/m1 umount /sys/fs/resctrl (2) mkdir /sys/fs/resctrl/c1 mkdir /sys/fs/resctrl/c1/mon_groups/m1 rmdir /sys/fs/resctrl/c1 The same reference count leak issue also exists in the error exit paths of mkdir in mkdir_rdt_prepare() and rdtgroup_mkdir_ctrl_mon(). Fix this issue by following changes to make sure the extra kernfs_node reference on rdtgroup is dropped before freeing the rdtgroup structure. (1) Introduce rdtgroup removal helper rdtgroup_remove() to wrap up kernfs_put() and kfree(). (2) Call rdtgroup_remove() in rdtgroup removal path where the rdtgroup structure is about to be freed by kfree(). (3) Call rdtgroup_remove() or kernfs_put() as appropriate in the error exit paths of mkdir where an extra reference is taken by kernfs_get(). Fixes: f3cbeacaa06e ("x86/intel_rdt/cqm: Add rmdir support") Fixes: e02737d5b826 ("x86/intel_rdt: Add tasks files") Fixes: 60cf5e101fd4 ("x86/intel_rdt: Add mkdir to resctrl file system") Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1604085088-31707-1-git-send-email-xiaochen.shen@intel.com
| * | | | | x86/resctrl: Remove superfluous kernfs_get() calls to prevent refcount leakXiaochen Shen2020-11-241-33/+2
| | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Willem reported growing of kernfs_node_cache entries in slabtop when repeatedly creating and removing resctrl subdirectories as well as when repeatedly mounting and unmounting the resctrl filesystem. On resource group (control as well as monitoring) creation via a mkdir an extra kernfs_node reference is obtained to ensure that the rdtgroup structure remains accessible for the rdtgroup_kn_unlock() calls where it is removed on deletion. The kernfs_node reference count is dropped by kernfs_put() in rdtgroup_kn_unlock(). With the above explaining the need for one kernfs_get()/kernfs_put() pair in resctrl there are more places where a kernfs_node reference is obtained without a corresponding release. The excessive amount of reference count on kernfs nodes will never be dropped to 0 and the kernfs nodes will never be freed in the call paths of rmdir and umount. It leads to reference count leak and kernfs_node_cache memory leak. Remove the superfluous kernfs_get() calls and expand the existing comments surrounding the remaining kernfs_get()/kernfs_put() pair that remains in use. Superfluous kernfs_get() calls are removed from two areas: (1) In call paths of mount and mkdir, when kernfs nodes for "info", "mon_groups" and "mon_data" directories and sub-directories are created, the reference count of newly created kernfs node is set to 1. But after kernfs_create_dir() returns, superfluous kernfs_get() are called to take an additional reference. (2) kernfs_get() calls in rmdir call paths. Fixes: 17eafd076291 ("x86/intel_rdt: Split resource group removal in two") Fixes: 4af4a88e0c92 ("x86/intel_rdt/cqm: Add mount,umount support") Fixes: f3cbeacaa06e ("x86/intel_rdt/cqm: Add rmdir support") Fixes: d89b7379015f ("x86/intel_rdt/cqm: Add mon_data") Fixes: c7d9aac61311 ("x86/intel_rdt/cqm: Add mkdir support for RDT monitoring") Fixes: 5dc1d5c6bac2 ("x86/intel_rdt: Simplify info and base file lists") Fixes: 60cf5e101fd4 ("x86/intel_rdt: Add mkdir to resctrl file system") Fixes: 4e978d06dedb ("x86/intel_rdt: Add "info" files to resctrl file system") Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Willem de Bruijn <willemb@google.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1604085053-31639-1-git-send-email-xiaochen.shen@intel.com
* | | | | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2020-11-277-63/+51
|\ \ \ \ \ | | |_|_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kvm fixes from Paolo Bonzini: "ARM: - Fix alignment of the new HYP sections - Fix GICR_TYPER access from userspace S390: - do not reset the global diag318 data for per-cpu reset - do not mark memory as protected too early - fix for destroy page ultravisor call x86: - fix for SEV debugging - fix incorrect return code - fix for 'noapic' with PIC in userspace and LAPIC in kernel - fix for 5-level paging" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: kvm: x86/mmu: Fix get_mmio_spte() on CPUs supporting 5-level PT KVM: x86: Fix split-irqchip vs interrupt injection window request KVM: x86: handle !lapic_in_kernel case in kvm_cpu_*_extint MAINTAINERS: Update email address for Sean Christopherson MAINTAINERS: add uv.c also to KVM/s390 s390/uv: handle destroy page legacy interface KVM: arm64: vgic-v3: Drop the reporting of GICR_TYPER.Last for userspace KVM: SVM: fix error return code in svm_create_vcpu() KVM: SVM: Fix offset computation bug in __sev_dbg_decrypt(). KVM: arm64: Correctly align nVHE percpu data KVM: s390: remove diag318 reset code KVM: s390: pv: Mark mm as protected after the set secure parameters and improve cleanup
| * | | | kvm: x86/mmu: Fix get_mmio_spte() on CPUs supporting 5-level PTVitaly Kuznetsov2020-11-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 95fb5b0258b7 ("kvm: x86/mmu: Support MMIO in the TDP MMU") caused the following WARNING on an Intel Ice Lake CPU: get_mmio_spte: detect reserved bits on spte, addr 0xb80a0, dump hierarchy: ------ spte 0xb80a0 level 5. ------ spte 0xfcd210107 level 4. ------ spte 0x1004c40107 level 3. ------ spte 0x1004c41107 level 2. ------ spte 0x1db00000000b83b6 level 1. WARNING: CPU: 109 PID: 10254 at arch/x86/kvm/mmu/mmu.c:3569 kvm_mmu_page_fault.cold.150+0x54/0x22f [kvm] ... Call Trace: ? kvm_io_bus_get_first_dev+0x55/0x110 [kvm] vcpu_enter_guest+0xaa1/0x16a0 [kvm] ? vmx_get_cs_db_l_bits+0x17/0x30 [kvm_intel] ? skip_emulated_instruction+0xaa/0x150 [kvm_intel] kvm_arch_vcpu_ioctl_run+0xca/0x520 [kvm] The guest triggering this crashes. Note, this happens with the traditional MMU and EPT enabled, not with the newly introduced TDP MMU. Turns out, there was a subtle change in the above mentioned commit. Previously, walk_shadow_page_get_mmio_spte() was setting 'root' to 'iterator.level' which is returned by shadow_walk_init() and this equals to 'vcpu->arch.mmu->shadow_root_level'. Now, get_mmio_spte() sets it to 'int root = vcpu->arch.mmu->root_level'. The difference between 'root_level' and 'shadow_root_level' on CPUs supporting 5-level page tables is that in some case we don't want to use 5-level, in particular when 'cpuid_maxphyaddr(vcpu) <= 48' kvm_mmu_get_tdp_level() returns '4'. In case upper layer is not used, the corresponding SPTE will fail '__is_rsvd_bits_set()' check. Revert to using 'shadow_root_level'. Fixes: 95fb5b0258b7 ("kvm: x86/mmu: Support MMIO in the TDP MMU") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20201126110206.2118959-1-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: x86: Fix split-irqchip vs interrupt injection window requestPaolo Bonzini2020-11-273-9/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kvm_cpu_accept_dm_intr and kvm_vcpu_ready_for_interrupt_injection are a hodge-podge of conditions, hacked together to get something that more or less works. But what is actually needed is much simpler; in both cases the fundamental question is, do we have a place to stash an interrupt if userspace does KVM_INTERRUPT? In userspace irqchip mode, that is !vcpu->arch.interrupt.injected. Currently kvm_event_needs_reinjection(vcpu) covers it, but it is unnecessarily restrictive. In split irqchip mode it's a bit more complicated, we need to check kvm_apic_accept_pic_intr(vcpu) (the IRQ window exit is basically an INTACK cycle and thus requires ExtINTs not to be masked) as well as !pending_userspace_extint(vcpu). However, there is no need to check kvm_event_needs_reinjection(vcpu), since split irqchip keeps pending ExtINT state separate from event injection state, and checking kvm_cpu_has_interrupt(vcpu) is wrong too since ExtINT has higher priority than APIC interrupts. In fact the latter fixes a bug: when userspace requests an IRQ window vmexit, an interrupt in the local APIC can cause kvm_cpu_has_interrupt() to be true and thus kvm_vcpu_ready_for_interrupt_injection() to return false. When this happens, vcpu_run does not exit to userspace but the interrupt window vmexits keep occurring. The VM loops without any hope of making progress. Once we try to fix these with something like return kvm_arch_interrupt_allowed(vcpu) && - !kvm_cpu_has_interrupt(vcpu) && - !kvm_event_needs_reinjection(vcpu) && - kvm_cpu_accept_dm_intr(vcpu); + (!lapic_in_kernel(vcpu) + ? !vcpu->arch.interrupt.injected + : (kvm_apic_accept_pic_intr(vcpu) + && !pending_userspace_extint(v))); we realize two things. First, thanks to the previous patch the complex conditional can reuse !kvm_cpu_has_extint(vcpu). Second, the interrupt window request in vcpu_enter_guest() bool req_int_win = dm_request_for_irq_injection(vcpu) && kvm_cpu_accept_dm_intr(vcpu); should be kept in sync with kvm_vcpu_ready_for_interrupt_injection(): it is unnecessary to ask the processor for an interrupt window if we would not be able to return to userspace. Therefore, kvm_cpu_accept_dm_intr(vcpu) is basically !kvm_cpu_has_extint(vcpu) ANDed with the existing check for masked ExtINT. It all makes sense: - we can accept an interrupt from userspace if there is a place to stash it (and, for irqchip split, ExtINTs are not masked). Interrupts from userspace _can_ be accepted even if right now EFLAGS.IF=0. - in order to tell userspace we will inject its interrupt ("IRQ window open" i.e. kvm_vcpu_ready_for_interrupt_injection), both KVM and the vCPU need to be ready to accept the interrupt. ... and this is what the patch implements. Reported-by: David Woodhouse <dwmw@amazon.co.uk> Analyzed-by: David Woodhouse <dwmw@amazon.co.uk> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Nikos Tsironis <ntsironis@arrikto.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Tested-by: David Woodhouse <dwmw@amazon.co.uk>
| * | | | KVM: x86: handle !lapic_in_kernel case in kvm_cpu_*_extintPaolo Bonzini2020-11-272-51/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Centralize handling of interrupts from the userspace APIC in kvm_cpu_has_extint and kvm_cpu_get_extint, since userspace APIC interrupts are handled more or less the same as ExtINTs are with split irqchip. This removes duplicated code from kvm_cpu_has_injectable_intr and kvm_cpu_has_interrupt, and makes the code more similar between kvm_cpu_has_{extint,interrupt} on one side and kvm_cpu_get_{extint,interrupt} on the other. Cc: stable@vger.kernel.org Reviewed-by: Filippo Sironi <sironi@amazon.de> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Tested-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: SVM: fix error return code in svm_create_vcpu()Chen Zhou2020-11-171-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix to return a negative error code from the error handling case instead of 0 in function svm_create_vcpu(), as done elsewhere in this function. Fixes: f4c847a95654 ("KVM: SVM: refactor msr permission bitmap allocation") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Chen Zhou <chenzhou10@huawei.com> Message-Id: <20201117025426.167824-1-chenzhou10@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: SVM: Fix offset computation bug in __sev_dbg_decrypt().Ashish Kalra2020-11-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix offset computation in __sev_dbg_decrypt() to include the source paddr before it is rounded down to be aligned to 16 bytes as required by SEV API. This fixes incorrect guest memory dumps observed when using qemu monitor. Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Message-Id: <20201110224205.29444-1-Ashish.Kalra@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | | | | Merge tag 'iommu-fixes' of ↵Linus Torvalds2020-11-271-4/+1
|\ \ \ \ \ | |_|/ / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull iommu fixes from Will Deacon: "Here's another round of IOMMU fixes for -rc6 consisting mainly of a bunch of independent driver fixes. Thomas agreed for me to take the x86 'tboot' fix here, as it fixes a regression introduced by a vt-d change. - Fix intel iommu driver when running on devices without VCCAP_REG - Fix swiotlb and "iommu=pt" interaction under TXT (tboot) - Fix missing return value check during device probe() - Fix probe ordering for Qualcomm SMMU implementation - Ensure page-sized mappings are used for AMD IOMMU buffers with SNP RMP" * tag 'iommu-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: iommu/vt-d: Don't read VCCAP register unless it exists x86/tboot: Don't disable swiotlb when iommu is forced on iommu: Check return of __iommu_attach_device() arm-smmu-qcom: Ensure the qcom_scm driver has finished probing iommu/amd: Enforce 4k mapping for certain IOMMU data structures
| * | | | x86/tboot: Don't disable swiotlb when iommu is forced onLu Baolu2020-11-251-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit 327d5b2fee91c ("iommu/vt-d: Allow 32bit devices to uses DMA domain"), swiotlb could also be used for direct memory access if IOMMU is enabled but a device is configured to pass through the DMA translation. Keep swiotlb when IOMMU is forced on, otherwise, some devices won't work if "iommu=pt" kernel parameter is used. Fixes: 327d5b2fee91 ("iommu/vt-d: Allow 32bit devices to uses DMA domain") Reported-and-tested-by: Adrian Huang <ahuang12@lenovo.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Link: https://lore.kernel.org/r/20201125014124.4070776-1-baolu.lu@linux.intel.com Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=210237 Signed-off-by: Will Deacon <will@kernel.org>
* | | | | Merge tag 'perf-urgent-2020-11-22' of ↵Linus Torvalds2020-11-224-24/+12
|\ \ \ \ \ | | |_|_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fix from Thomas Gleixner: "A single fix for the x86 perf sysfs interfaces which used kobject attributes instead of device attributes and therefore making clang's control flow integrity checker upset" * tag 'perf-urgent-2020-11-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: fix sysfs type mismatches
| * | | | perf/x86: fix sysfs type mismatchesSami Tolvanen2020-11-174-24/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change switches rapl to use PMU_FORMAT_ATTR, and fixes two other macros to use device_attribute instead of kobj_attribute to avoid callback type mismatches that trip indirect call checking with Clang's Control-Flow Integrity (CFI). Reported-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20201113183126.1239404-1-samitolvanen@google.com
* | | | | Merge tag 'efi-urgent-for-v5.10-rc3' of ↵Linus Torvalds2020-11-221-11/+13
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI fixes from Borislav Petkov: "Forwarded EFI fixes from Ard Biesheuvel: - fix memory leak in efivarfs driver - fix HYP mode issue in 32-bit ARM version of the EFI stub when built in Thumb2 mode - avoid leaking EFI pgd pages on allocation failure" * tag 'efi-urgent-for-v5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: efi/x86: Free efi_pgd with free_pages() efivarfs: fix memory leak in efivarfs_create() efi/arm: set HSCTLR Thumb2 bit correctly for HVC calls from HYP
| * | | | | efi/x86: Free efi_pgd with free_pages()Arvind Sankar2020-11-101-11/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit d9e9a6418065 ("x86/mm/pti: Allocate a separate user PGD") changed the PGD allocation to allocate PGD_ALLOCATION_ORDER pages, so in the error path it should be freed using free_pages() rather than free_page(). Commit 06ace26f4e6f ("x86/efi: Free efi_pgd with free_pages()") fixed one instance of this, but missed another. Move the freeing out-of-line to avoid code duplication and fix this bug. Fixes: d9e9a6418065 ("x86/mm/pti: Allocate a separate user PGD") Link: https://lore.kernel.org/r/20201110163919.1134431-1-nivedita@alum.mit.edu Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
* | | | | | Merge tag 'x86_urgent_for_v5.10-rc5' of ↵Linus Torvalds2020-11-222-57/+29
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - An IOMMU VT-d build fix when CONFIG_PCI_ATS=n along with a revert of same because the proper one is going through the IOMMU tree (Thomas Gleixner) - An Intel microcode loader fix to save the correct microcode patch to apply during resume (Chen Yu) - A fix to not access user memory of other processes when dumping opcode bytes (Thomas Gleixner) * tag 'x86_urgent_for_v5.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Revert "iommu/vt-d: Take CONFIG_PCI_ATS into account" x86/dumpstack: Do not try to access user space code of other tasks x86/microcode/intel: Check patch signature before saving microcode for early loading iommu/vt-d: Take CONFIG_PCI_ATS into account
| * | | | | | x86/dumpstack: Do not try to access user space code of other tasksThomas Gleixner2020-11-181-4/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sysrq-t ends up invoking show_opcodes() for each task which tries to access the user space code of other processes, which is obviously bogus. It either manages to dump where the foreign task's regs->ip points to in a valid mapping of the current task or triggers a pagefault and prints "Code: Bad RIP value.". Both is just wrong. Add a safeguard in copy_code() and check whether the @regs pointer matches currents pt_regs. If not, do not even try to access it. While at it, add commentary why using copy_from_user_nmi() is safe in copy_code() even if the function name suggests otherwise. Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Oleg Nesterov <oleg@redhat.com> Tested-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201117202753.667274723@linutronix.de
| * | | | | | x86/microcode/intel: Check patch signature before saving microcode for early ↵Chen Yu2020-11-171-53/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | loading Currently, scan_microcode() leverages microcode_matches() to check if the microcode matches the CPU by comparing the family and model. However, the processor stepping and flags of the microcode signature should also be considered when saving a microcode patch for early update. Use find_matching_signature() in scan_microcode() and get rid of the now-unused microcode_matches() which is a good cleanup in itself. Complete the verification of the patch being saved for early loading in save_microcode_patch() directly. This needs to be done there too because save_mc_for_early() will call save_microcode_patch() too. The second reason why this needs to be done is because the loader still tries to support, at least hypothetically, mixed-steppings systems and thus adds all patches to the cache that belong to the same CPU model albeit with different steppings. For example: microcode: CPU: sig=0x906ec, pf=0x2, rev=0xd6 microcode: mc_saved[0]: sig=0x906e9, pf=0x2a, rev=0xd6, total size=0x19400, date = 2020-04-23 microcode: mc_saved[1]: sig=0x906ea, pf=0x22, rev=0xd6, total size=0x19000, date = 2020-04-27 microcode: mc_saved[2]: sig=0x906eb, pf=0x2, rev=0xd6, total size=0x19400, date = 2020-04-23 microcode: mc_saved[3]: sig=0x906ec, pf=0x22, rev=0xd6, total size=0x19000, date = 2020-04-27 microcode: mc_saved[4]: sig=0x906ed, pf=0x22, rev=0xd6, total size=0x19400, date = 2020-04-23 The patch which is being saved for early loading, however, can only be the one which fits the CPU this runs on so do the signature verification before saving. [ bp: Do signature verification in save_microcode_patch() and rewrite commit message. ] Fixes: ec400ddeff20 ("x86/microcode_intel_early.c: Early update ucode on Intel's CPU") Signed-off-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: stable@vger.kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=208535 Link: https://lkml.kernel.org/r/20201113015923.13960-1-yu.c.chen@intel.com
* | | | | | | mm: fix phys_to_target_node() and memory_add_physaddr_to_nid() exportsDan Williams2020-11-222-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The core-mm has a default __weak implementation of phys_to_target_node() to mirror the weak definition of memory_add_physaddr_to_nid(). That symbol is exported for modules. However, while the export in mm/memory_hotplug.c exported the symbol in the configuration cases of: CONFIG_NUMA_KEEP_MEMINFO=y CONFIG_MEMORY_HOTPLUG=y ...and: CONFIG_NUMA_KEEP_MEMINFO=n CONFIG_MEMORY_HOTPLUG=y ...it failed to export the symbol in the case of: CONFIG_NUMA_KEEP_MEMINFO=y CONFIG_MEMORY_HOTPLUG=n Not only is that broken, but Christoph points out that the kernel should not be exporting any __weak symbol, which means that memory_add_physaddr_to_nid() example that phys_to_target_node() copied is broken too. Rework the definition of phys_to_target_node() and memory_add_physaddr_to_nid() to not require weak symbols. Move to the common arch override design-pattern of an asm header defining a symbol to replace the default implementation. The only common header that all memory_add_physaddr_to_nid() producing architectures implement is asm/sparsemem.h. In fact, powerpc already defines its memory_add_physaddr_to_nid() helper in sparsemem.h. Double-down on that observation and define phys_to_target_node() where necessary in asm/sparsemem.h. An alternate consideration that was discarded was to put this override in asm/numa.h, but that entangles with the definition of MAX_NUMNODES relative to the inclusion of linux/nodemask.h, and requires powerpc to grow a new header. The dependency on NUMA_KEEP_MEMINFO for DEV_DAX_HMEM_DEVICES is invalid now that the symbol is properly exported / stubbed in all combinations of CONFIG_NUMA_KEEP_MEMINFO and CONFIG_MEMORY_HOTPLUG. [dan.j.williams@intel.com: v4] Link: https://lkml.kernel.org/r/160461461867.1505359.5301571728749534585.stgit@dwillia2-desk3.amr.corp.intel.com [dan.j.williams@intel.com: powerpc: fix create_section_mapping compile warning] Link: https://lkml.kernel.org/r/160558386174.2948926.2740149041249041764.stgit@dwillia2-desk3.amr.corp.intel.com Fixes: a035b6bf863e ("mm/memory_hotplug: introduce default phys_to_target_node() implementation") Reported-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Thomas Gleixner <tglx@linutronix.de> Reported-by: kernel test robot <lkp@intel.com> Reported-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: https://lkml.kernel.org/r/160447639846.1133764.7044090803980177548.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | Merge tag 'for-linus-5.10b-rc5-tag' of ↵Linus Torvalds2020-11-201-1/+11
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fix from Juergen Gross: "A single fix for avoiding WARN splats when booting a Xen guest with nosmt" * tag 'for-linus-5.10b-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/xen: don't unbind uninitialized lock_kicker_irq
| * | | | | | | x86/xen: don't unbind uninitialized lock_kicker_irqBrian Masney2020-11-091-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When booting a hyperthreaded system with the kernel parameter 'mitigations=auto,nosmt', the following warning occurs: WARNING: CPU: 0 PID: 1 at drivers/xen/events/events_base.c:1112 unbind_from_irqhandler+0x4e/0x60 ... Hardware name: Xen HVM domU, BIOS 4.2.amazon 08/24/2006 ... Call Trace: xen_uninit_lock_cpu+0x28/0x62 xen_hvm_cpu_die+0x21/0x30 takedown_cpu+0x9c/0xe0 ? trace_suspend_resume+0x60/0x60 cpuhp_invoke_callback+0x9a/0x530 _cpu_up+0x11a/0x130 cpu_up+0x7e/0xc0 bringup_nonboot_cpus+0x48/0x50 smp_init+0x26/0x79 kernel_init_freeable+0xea/0x229 ? rest_init+0xaa/0xaa kernel_init+0xa/0x106 ret_from_fork+0x35/0x40 The secondary CPUs are not activated with the nosmt mitigations and only the primary thread on each CPU core is used. In this situation, xen_hvm_smp_prepare_cpus(), and more importantly xen_init_lock_cpu(), is not called, so the lock_kicker_irq is not initialized for the secondary CPUs. Let's fix this by exiting early in xen_uninit_lock_cpu() if the irq is not set to avoid the warning from above for each secondary CPU. Signed-off-by: Brian Masney <bmasney@redhat.com> Link: https://lore.kernel.org/r/20201107011119.631442-1-bmasney@redhat.com Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
generated by cgit (git 2.34.1) at 2025-02-25 02:42:52 +0000