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2024-04-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski11-145/+128
Cross-merge networking fixes after downstream PR. Conflicts: include/trace/events/rpcgss.h 386f4a737964 ("trace: events: cleanup deprecated strncpy uses") a4833e3abae1 ("SUNRPC: Fix rpcgss_context trace event acceptor field") Adjacent changes: drivers/net/ethernet/intel/ice/ice_tc_lib.c 2cca35f5dd78 ("ice: Fix checking for unsupported keys on non-tunnel device") 784feaa65dfd ("ice: Add support for PFCP hardware offload in switchdev") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-14Merge tag 'x86-urgent-2024-04-14' of ↵Linus Torvalds8-119/+115
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 fixes from Ingo Molnar: - Follow up fixes for the BHI mitigations code - Fix !SPECULATION_MITIGATIONS bug not turning off mitigations as expected - Work around an APIC emulation bug when the kernel is built with Clang and run as a SEV guest - Follow up x86 topology fixes * tag 'x86-urgent-2024-04-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu/amd: Move TOPOEXT enablement into the topology parser x86/cpu/amd: Make the NODEID_MSR union actually work x86/cpu/amd: Make the CPUID 0x80000008 parser correct x86/bugs: Replace CONFIG_SPECTRE_BHI_{ON,OFF} with CONFIG_MITIGATION_SPECTRE_BHI x86/bugs: Remove CONFIG_BHI_MITIGATION_AUTO and spectre_bhi=auto x86/bugs: Clarify that syscall hardening isn't a BHI mitigation x86/bugs: Fix BHI handling of RRSBA x86/bugs: Rename various 'ia32_cap' variables to 'x86_arch_cap_msr' x86/bugs: Cache the value of MSR_IA32_ARCH_CAPABILITIES x86/bugs: Fix BHI documentation x86/cpu: Actually turn off mitigations by default for SPECULATION_MITIGATIONS=n x86/topology: Don't update cpu_possible_map in topo_set_cpuids() x86/bugs: Fix return type of spectre_bhi_state() x86/apic: Force native_apic_mem_read() to use the MOV instruction
2024-04-14Merge tag 'perf-urgent-2024-04-14' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf event fix from Ingo Molnar: "Fix the x86 PMU multi-counter code returning invalid data in certain circumstances" * tag 'perf-urgent-2024-04-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: Fix out of range data
2024-04-12x86/cpu/amd: Move TOPOEXT enablement into the topology parserThomas Gleixner2-15/+21
The topology rework missed that early_init_amd() tries to re-enable the Topology Extensions when the BIOS disabled them. The new parser is invoked before early_init_amd() so the re-enable attempt happens too late. Move it into the AMD specific topology parser code where it belongs. Fixes: f7fb3b2dd92c ("x86/cpu: Provide an AMD/HYGON specific topology parser") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/878r1j260l.ffs@tglx
2024-04-12x86/cpu/amd: Make the NODEID_MSR union actually workThomas Gleixner1-3/+3
A system with NODEID_MSR was reported to crash during early boot without any output. The reason is that the union which is used for accessing the bitfields in the MSR is written wrongly and the resulting executable code accesses the wrong part of the MSR data. As a consequence a later division by that value results in 0 and that result is used for another division as divisor, which obviously does not work well. The magic world of C, unions and bitfields: union { u64 bita : 3, bitb : 3; u64 all; } x; x.all = foo(); a = x.bita; b = x.bitb; results in the effective executable code of: a = b = x.bita; because bita and bitb are treated as union members and therefore both end up at bit offset 0. Wrapping the bitfield into an anonymous struct: union { struct { u64 bita : 3, bitb : 3; }; u64 all; } x; works like expected. Rework the NODEID_MSR union in exactly that way to cure the problem. Fixes: f7fb3b2dd92c ("x86/cpu: Provide an AMD/HYGON specific topology parser") Reported-by: "kernelci.org bot" <bot@kernelci.org> Reported-by: Laura Nao <laura.nao@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Laura Nao <laura.nao@collabora.com> Link: https://lore.kernel.org/r/20240410194311.596282919@linutronix.de Closes: https://lore.kernel.org/all/20240322175210.124416-1-laura.nao@collabora.com/
2024-04-12x86/cpu/amd: Make the CPUID 0x80000008 parser correctThomas Gleixner1-6/+18
CPUID 0x80000008 ECX.cpu_nthreads describes the number of threads in the package. The parser uses this value to initialize the SMT domain level. That's wrong because cpu_nthreads does not describe the number of threads per physical core. So this needs to set the CORE domain level and let the later parsers set the SMT shift if available. Preset the SMT domain level with the assumption of one thread per core, which is correct ifrt here are no other CPUID leafs to parse, and propagate cpu_nthreads and the core level APIC bitwidth into the CORE domain. Fixes: f7fb3b2dd92c ("x86/cpu: Provide an AMD/HYGON specific topology parser") Reported-by: "kernelci.org bot" <bot@kernelci.org> Reported-by: Laura Nao <laura.nao@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Laura Nao <laura.nao@collabora.com> Link: https://lore.kernel.org/r/20240410194311.535206450@linutronix.de
2024-04-12x86/bugs: Replace CONFIG_SPECTRE_BHI_{ON,OFF} with CONFIG_MITIGATION_SPECTRE_BHIJosh Poimboeuf2-15/+4
For consistency with the other CONFIG_MITIGATION_* options, replace the CONFIG_SPECTRE_BHI_{ON,OFF} options with a single CONFIG_MITIGATION_SPECTRE_BHI option. [ mingo: Fix ] Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Sean Christopherson <seanjc@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nikolay Borisov <nik.borisov@suse.com> Link: https://lore.kernel.org/r/3833812ea63e7fdbe36bf8b932e63f70d18e2a2a.1712813475.git.jpoimboe@kernel.org
2024-04-12x86/bugs: Remove CONFIG_BHI_MITIGATION_AUTO and spectre_bhi=autoJosh Poimboeuf2-14/+1
Unlike most other mitigations' "auto" options, spectre_bhi=auto only mitigates newer systems, which is confusing and not particularly useful. Remove it. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/412e9dc87971b622bbbaf64740ebc1f140bff343.1712813475.git.jpoimboe@kernel.org
2024-04-12Merge tag 'hyperv-fixes-signed-20240411' of ↵Linus Torvalds2-26/+12
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv fixes from Wei Liu: - Some cosmetic changes (Erni Sri Satya Vennela, Li Zhijian) - Introduce hv_numa_node_to_pxm_info() (Nuno Das Neves) - Fix KVP daemon to handle IPv4 and IPv6 combination for keyfile format (Shradha Gupta) - Avoid freeing decrypted memory in a confidential VM (Rick Edgecombe and Michael Kelley) * tag 'hyperv-fixes-signed-20240411' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: Drivers: hv: vmbus: Don't free ring buffers that couldn't be re-encrypted uio_hv_generic: Don't free decrypted memory hv_netvsc: Don't free decrypted memory Drivers: hv: vmbus: Track decrypted status in vmbus_gpadl Drivers: hv: vmbus: Leak pages if set_memory_encrypted() fails hv/hv_kvp_daemon: Handle IPv4 and Ipv6 combination for keyfile format hv: vmbus: Convert sprintf() family to sysfs_emit() family mshyperv: Introduce hv_numa_node_to_pxm_info() x86/hyperv: Cosmetic changes for hv_apic.c
2024-04-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski34-100/+510
Cross-merge networking fixes after downstream PR. Conflicts: net/unix/garbage.c 47d8ac011fe1 ("af_unix: Fix garbage collector racing against connect()") 4090fa373f0e ("af_unix: Replace garbage collection algorithm.") Adjacent changes: drivers/net/ethernet/broadcom/bnxt/bnxt.c faa12ca24558 ("bnxt_en: Reset PTP tx_avail after possible firmware reset") b3d0083caf9a ("bnxt_en: Support RSS contexts in ethtool .{get|set}_rxfh()") drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c 7ac10c7d728d ("bnxt_en: Fix possible memory leak in bnxt_rdma_aux_device_init()") 194fad5b2781 ("bnxt_en: Refactor bnxt_rdma_aux_device_init/uninit functions") drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c 958f56e48385 ("net/mlx5e: Un-expose functions in en.h") 49e6c9387051 ("net/mlx5e: RSS, Block XOR hash with over 128 channels") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-11x86/bugs: Clarify that syscall hardening isn't a BHI mitigationJosh Poimboeuf1-3/+3
While syscall hardening helps prevent some BHI attacks, there's still other low-hanging fruit remaining. Don't classify it as a mitigation and make it clear that the system may still be vulnerable if it doesn't have a HW or SW mitigation enabled. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/b5951dae3fdee7f1520d5136a27be3bdfe95f88b.1712813475.git.jpoimboe@kernel.org
2024-04-11x86/bugs: Fix BHI handling of RRSBAJosh Poimboeuf1-12/+18
The ARCH_CAP_RRSBA check isn't correct: RRSBA may have already been disabled by the Spectre v2 mitigation (or can otherwise be disabled by the BHI mitigation itself if needed). In that case retpolines are fine. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/6f56f13da34a0834b69163467449be7f58f253dc.1712813475.git.jpoimboe@kernel.org
2024-04-11x86/bugs: Rename various 'ia32_cap' variables to 'x86_arch_cap_msr'Ingo Molnar3-42/+42
So we are using the 'ia32_cap' value in a number of places, which got its name from MSR_IA32_ARCH_CAPABILITIES MSR register. But there's very little 'IA32' about it - this isn't 32-bit only code, nor does it originate from there, it's just a historic quirk that many Intel MSR names are prefixed with IA32_. This is already clear from the helper method around the MSR: x86_read_arch_cap_msr(), which doesn't have the IA32 prefix. So rename 'ia32_cap' to 'x86_arch_cap_msr' to be consistent with its role and with the naming of the helper function. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Nikolay Borisov <nik.borisov@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/9592a18a814368e75f8f4b9d74d3883aa4fd1eaf.1712813475.git.jpoimboe@kernel.org
2024-04-11x86/bugs: Cache the value of MSR_IA32_ARCH_CAPABILITIESJosh Poimboeuf1-15/+7
There's no need to keep reading MSR_IA32_ARCH_CAPABILITIES over and over. It's even read in the BHI sysfs function which is a big no-no. Just read it once and cache it. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/9592a18a814368e75f8f4b9d74d3883aa4fd1eaf.1712813475.git.jpoimboe@kernel.org
2024-04-10x86/topology: Don't update cpu_possible_map in topo_set_cpuids()Thomas Gleixner1-2/+5
topo_set_cpuids() updates cpu_present_map and cpu_possible map. It is invoked during enumeration and "physical hotplug" operations. In the latter case this results in a kernel crash because cpu_possible_map is marked read only after init completes. There is no reason to update cpu_possible_map in that function. During enumeration cpu_possible_map is not relevant and gets fully initialized after enumeration completed. On "physical hotplug" the bit is already set because the kernel allows only CPUs to be plugged which have been enumerated and associated to a CPU number during early boot. Remove the bogus update of cpu_possible_map. Fixes: 0e53e7b656cf ("x86/cpu/topology: Sanitize the APIC admission logic") Reported-by: Jonathan Cameron <Jonathan.Cameron@Huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/87ttkc6kwx.ffs@tglx
2024-04-10x86/bugs: Fix return type of spectre_bhi_state()Daniel Sneddon1-1/+1
The definition of spectre_bhi_state() incorrectly returns a const char * const. This causes the a compiler warning when building with W=1: warning: type qualifiers ignored on function return type [-Wignored-qualifiers] 2812 | static const char * const spectre_bhi_state(void) Remove the const qualifier from the pointer. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Reported-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20240409230806.1545822-1-daniel.sneddon@linux.intel.com
2024-04-10Merge branch 'linus' into x86/urgent, to pick up dependent commitsIngo Molnar17-43/+317
Prepare to fix aspects of the new BHI code. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-04-10perf/x86: Fix out of range dataNamhyung Kim1-0/+1
On x86 each struct cpu_hw_events maintains a table for counter assignment but it missed to update one for the deleted event in x86_pmu_del(). This can make perf_clear_dirty_counters() reset used counter if it's called before event scheduling or enabling. Then it would return out of range data which doesn't make sense. The following code can reproduce the problem. $ cat repro.c #include <pthread.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <linux/perf_event.h> #include <sys/ioctl.h> #include <sys/mman.h> #include <sys/syscall.h> struct perf_event_attr attr = { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CPU_CYCLES, .disabled = 1, }; void *worker(void *arg) { int cpu = (long)arg; int fd1 = syscall(SYS_perf_event_open, &attr, -1, cpu, -1, 0); int fd2 = syscall(SYS_perf_event_open, &attr, -1, cpu, -1, 0); void *p; do { ioctl(fd1, PERF_EVENT_IOC_ENABLE, 0); p = mmap(NULL, 4096, PROT_READ, MAP_SHARED, fd1, 0); ioctl(fd2, PERF_EVENT_IOC_ENABLE, 0); ioctl(fd2, PERF_EVENT_IOC_DISABLE, 0); munmap(p, 4096); ioctl(fd1, PERF_EVENT_IOC_DISABLE, 0); } while (1); return NULL; } int main(void) { int i; int n = sysconf(_SC_NPROCESSORS_ONLN); pthread_t *th = calloc(n, sizeof(*th)); for (i = 0; i < n; i++) pthread_create(&th[i], NULL, worker, (void *)(long)i); for (i = 0; i < n; i++) pthread_join(th[i], NULL); free(th); return 0; } And you can see the out of range data using perf stat like this. Probably it'd be easier to see on a large machine. $ gcc -o repro repro.c -pthread $ ./repro & $ sudo perf stat -A -I 1000 2>&1 | awk '{ if (length($3) > 15) print }' 1.001028462 CPU6 196,719,295,683,763 cycles # 194290.996 GHz (71.54%) 1.001028462 CPU3 396,077,485,787,730 branch-misses # 15804359784.80% of all branches (71.07%) 1.001028462 CPU17 197,608,350,727,877 branch-misses # 14594186554.56% of all branches (71.22%) 2.020064073 CPU4 198,372,472,612,140 cycles # 194681.113 GHz (70.95%) 2.020064073 CPU6 199,419,277,896,696 cycles # 195720.007 GHz (70.57%) 2.020064073 CPU20 198,147,174,025,639 cycles # 194474.654 GHz (71.03%) 2.020064073 CPU20 198,421,240,580,145 stalled-cycles-frontend # 100.14% frontend cycles idle (70.93%) 3.037443155 CPU4 197,382,689,923,416 cycles # 194043.065 GHz (71.30%) 3.037443155 CPU20 196,324,797,879,414 cycles # 193003.773 GHz (71.69%) 3.037443155 CPU5 197,679,956,608,205 stalled-cycles-backend # 1315606428.66% backend cycles idle (71.19%) 3.037443155 CPU5 198,571,860,474,851 instructions # 13215422.58 insn per cycle It should move the contents in the cpuc->assign as well. Fixes: 5471eea5d3bf ("perf/x86: Reset the dirty counter to prevent the leak for an RDPMC task") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Kan Liang <kan.liang@linux.intel.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240306061003.1894224-1-namhyung@kernel.org
2024-04-09Merge tag 'nativebhi' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds17-43/+317
Pull x86 mitigations from Thomas Gleixner: "Mitigations for the native BHI hardware vulnerabilty: Branch History Injection (BHI) attacks may allow a malicious application to influence indirect branch prediction in kernel by poisoning the branch history. eIBRS isolates indirect branch targets in ring0. The BHB can still influence the choice of indirect branch predictor entry, and although branch predictor entries are isolated between modes when eIBRS is enabled, the BHB itself is not isolated between modes. Add mitigations against it either with the help of microcode or with software sequences for the affected CPUs" [ This also ends up enabling the full mitigation by default despite the system call hardening, because apparently there are other indirect calls that are still sufficiently reachable, and the 'auto' case just isn't hardened enough. We'll have some more inevitable tweaking in the future - Linus ] * tag 'nativebhi' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: KVM: x86: Add BHI_NO x86/bhi: Mitigate KVM by default x86/bhi: Add BHI mitigation knob x86/bhi: Enumerate Branch History Injection (BHI) bug x86/bhi: Define SPEC_CTRL_BHI_DIS_S x86/bhi: Add support for clearing branch history at syscall entry x86/syscall: Don't force use of indirect calls for system calls x86/bugs: Change commas to semicolons in 'spectre_v2' sysfs file
2024-04-08KVM: x86: Add BHI_NODaniel Sneddon1-1/+1
Intel processors that aren't vulnerable to BHI will set MSR_IA32_ARCH_CAPABILITIES[BHI_NO] = 1;. Guests may use this BHI_NO bit to determine if they need to implement BHI mitigations or not. Allow this bit to be passed to the guests. Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
2024-04-08x86/bhi: Mitigate KVM by defaultPawan Gupta4-2/+15
BHI mitigation mode spectre_bhi=auto does not deploy the software mitigation by default. In a cloud environment, it is a likely scenario where userspace is trusted but the guests are not trusted. Deploying system wide mitigation in such cases is not desirable. Update the auto mode to unconditionally mitigate against malicious guests. Deploy the software sequence at VMexit in auto mode also, when hardware mitigation is not available. Unlike the force =on mode, software sequence is not deployed at syscalls in auto mode. Suggested-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
2024-04-08x86/bhi: Add BHI mitigation knobPawan Gupta3-1/+115
Branch history clearing software sequences and hardware control BHI_DIS_S were defined to mitigate Branch History Injection (BHI). Add cmdline spectre_bhi={on|off|auto} to control BHI mitigation: auto - Deploy the hardware mitigation BHI_DIS_S, if available. on - Deploy the hardware mitigation BHI_DIS_S, if available, otherwise deploy the software sequence at syscall entry and VMexit. off - Turn off BHI mitigation. The default is auto mode which does not deploy the software sequence mitigation. This is because of the hardening done in the syscall dispatch path, which is the likely target of BHI. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
2024-04-08x86/bhi: Enumerate Branch History Injection (BHI) bugPawan Gupta3-8/+21
Mitigation for BHI is selected based on the bug enumeration. Add bits needed to enumerate BHI bug. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
2024-04-08x86/bhi: Define SPEC_CTRL_BHI_DIS_SDaniel Sneddon4-2/+8
Newer processors supports a hardware control BHI_DIS_S to mitigate Branch History Injection (BHI). Setting BHI_DIS_S protects the kernel from userspace BHI attacks without having to manually overwrite the branch history. Define MSR_SPEC_CTRL bit BHI_DIS_S and its enumeration CPUID.BHI_CTRL. Mitigation is enabled later. Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
2024-04-08x86/bhi: Add support for clearing branch history at syscall entryPawan Gupta7-3/+96
Branch History Injection (BHI) attacks may allow a malicious application to influence indirect branch prediction in kernel by poisoning the branch history. eIBRS isolates indirect branch targets in ring0. The BHB can still influence the choice of indirect branch predictor entry, and although branch predictor entries are isolated between modes when eIBRS is enabled, the BHB itself is not isolated between modes. Alder Lake and new processors supports a hardware control BHI_DIS_S to mitigate BHI. For older processors Intel has released a software sequence to clear the branch history on parts that don't support BHI_DIS_S. Add support to execute the software sequence at syscall entry and VMexit to overwrite the branch history. For now, branch history is not cleared at interrupt entry, as malicious applications are not believed to have sufficient control over the registers, since previous register state is cleared at interrupt entry. Researchers continue to poke at this area and it may become necessary to clear at interrupt entry as well in the future. This mitigation is only defined here. It is enabled later. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Co-developed-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
2024-04-08x86/syscall: Don't force use of indirect calls for system callsLinus Torvalds5-16/+50
Make <asm/syscall.h> build a switch statement instead, and the compiler can either decide to generate an indirect jump, or - more likely these days due to mitigations - just a series of conditional branches. Yes, the conditional branches also have branch prediction, but the branch prediction is much more controlled, in that it just causes speculatively running the wrong system call (harmless), rather than speculatively running possibly wrong random less controlled code gadgets. This doesn't mitigate other indirect calls, but the system call indirection is the first and most easily triggered case. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
2024-04-08x86/bugs: Change commas to semicolons in 'spectre_v2' sysfs fileJosh Poimboeuf1-12/+12
Change the format of the 'spectre_v2' vulnerabilities sysfs file slightly by converting the commas to semicolons, so that mitigations for future variants can be grouped together and separated by commas. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2024-04-08x86/apic: Force native_apic_mem_read() to use the MOV instructionAdam Dunlap1-1/+2
When done from a virtual machine, instructions that touch APIC memory must be emulated. By convention, MMIO accesses are typically performed via io.h helpers such as readl() or writeq() to simplify instruction emulation/decoding (ex: in KVM hosts and SEV guests) [0]. Currently, native_apic_mem_read() does not follow this convention, allowing the compiler to emit instructions other than the MOV instruction generated by readl(). In particular, when the kernel is compiled with clang and run as a SEV-ES or SEV-SNP guest, the compiler would emit a TESTL instruction which is not supported by the SEV-ES emulator, causing a boot failure in that environment. It is likely the same problem would happen in a TDX guest as that uses the same instruction emulator as SEV-ES. To make sure all emulators can emulate APIC memory reads via MOV, use the readl() function in native_apic_mem_read(). It is expected that any emulator would support MOV in any addressing mode as it is the most generic and is what is usually emitted currently. The TESTL instruction is emitted when native_apic_mem_read() is inlined into apic_mem_wait_icr_idle(). The emulator comes from insn_decode_mmio() in arch/x86/lib/insn-eval.c. It's not worth it to extend insn_decode_mmio() to support more instructions since, in theory, the compiler could choose to output nearly any instruction for such reads which would bloat the emulator beyond reason. [0] https://lore.kernel.org/all/20220405232939.73860-12-kirill.shutemov@linux.intel.com/ [ bp: Massage commit message, fix typos. ] Signed-off-by: Adam Dunlap <acdunlap@google.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Kevin Loughlin <kevinloughlin@google.com> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20240318230927.2191933-1-acdunlap@google.com
2024-04-07Merge tag 'x86-urgent-2024-04-07' of ↵Linus Torvalds14-39/+150
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: - Fix MCE timer reinit locking - Fix/improve CoCo guest random entropy pool init - Fix SEV-SNP late disable bugs - Fix false positive objtool build warning - Fix header dependency bug - Fix resctrl CPU offlining bug * tag 'x86-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/retpoline: Add NOENDBR annotation to the SRSO dummy return thunk x86/mce: Make sure to grab mce_sysfs_mutex in set_bank() x86/CPU/AMD: Track SNP host status with cc_platform_*() x86/cc: Add cc_platform_set/_clear() helpers x86/kvm/Kconfig: Have KVM_AMD_SEV select ARCH_HAS_CC_PLATFORM x86/coco: Require seeding RNG with RDRAND on CoCo systems x86/numa/32: Include missing <asm/pgtable_areas.h> x86/resctrl: Fix uninitialized memory read when last CPU of domain goes offline
2024-04-07Merge tag 'perf-urgent-2024-04-07' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 perf fix from Ingo Molnar: "Fix a combined PEBS events bug on x86 Intel CPUs" * tag 'perf-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel/ds: Don't clear ->pebs_data_cfg for the last PEBS event
2024-04-06x86/retpoline: Add NOENDBR annotation to the SRSO dummy return thunkBorislav Petkov (AMD)1-0/+1
srso_alias_untrain_ret() is special code, even if it is a dummy which is called in the !SRSO case, so annotate it like its real counterpart, to address the following objtool splat: vmlinux.o: warning: objtool: .export_symbol+0x2b290: data relocation to !ENDBR: srso_alias_untrain_ret+0x0 Fixes: 4535e1a4174c ("x86/bugs: Fix the SRSO mitigation on Zen3/4") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20240405144637.17908-1-bp@kernel.org
2024-04-06Merge branch 'linus' into x86/urgent, to pick up dependent commitIngo Molnar13-81/+149
We want to fix: 0e110732473e ("x86/retpoline: Do the necessary fixup to the Zen3/4 srso return thunk for !SRSO") So merge in Linus's latest into x86/urgent to have it available. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-04-05Merge tag 'mm-hotfixes-stable-2024-04-05-11-30' of ↵Linus Torvalds1-14/+35
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "8 hotfixes, 3 are cc:stable There are a couple of fixups for this cycle's vmalloc changes and one for the stackdepot changes. And a fix for a very old x86 PAT issue which can cause a warning splat" * tag 'mm-hotfixes-stable-2024-04-05-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: stackdepot: rename pool_index to pool_index_plus_1 x86/mm/pat: fix VM_PAT handling in COW mappings MAINTAINERS: change vmware.com addresses to broadcom.com selftests/mm: include strings.h for ffsl mm: vmalloc: fix lockdep warning mm: vmalloc: bail out early in find_vmap_area() if vmap is not init init: open output files from cpio unpacking with O_LARGEFILE mm/secretmem: fix GUP-fast succeeding on secretmem folios
2024-04-05x86/mm/pat: fix VM_PAT handling in COW mappingsDavid Hildenbrand1-14/+35
PAT handling won't do the right thing in COW mappings: the first PTE (or, in fact, all PTEs) can be replaced during write faults to point at anon folios. Reliably recovering the correct PFN and cachemode using follow_phys() from PTEs will not work in COW mappings. Using follow_phys(), we might just get the address+protection of the anon folio (which is very wrong), or fail on swap/nonswap entries, failing follow_phys() and triggering a WARN_ON_ONCE() in untrack_pfn() and track_pfn_copy(), not properly calling free_pfn_range(). In free_pfn_range(), we either wouldn't call memtype_free() or would call it with the wrong range, possibly leaking memory. To fix that, let's update follow_phys() to refuse returning anon folios, and fallback to using the stored PFN inside vma->vm_pgoff for COW mappings if we run into that. We will now properly handle untrack_pfn() with COW mappings, where we don't need the cachemode. We'll have to fail fork()->track_pfn_copy() if the first page was replaced by an anon folio, though: we'd have to store the cachemode in the VMA to make this work, likely growing the VMA size. For now, lets keep it simple and let track_pfn_copy() just fail in that case: it would have failed in the past with swap/nonswap entries already, and it would have done the wrong thing with anon folios. Simple reproducer to trigger the WARN_ON_ONCE() in untrack_pfn(): <--- C reproducer ---> #include <stdio.h> #include <sys/mman.h> #include <unistd.h> #include <liburing.h> int main(void) { struct io_uring_params p = {}; int ring_fd; size_t size; char *map; ring_fd = io_uring_setup(1, &p); if (ring_fd < 0) { perror("io_uring_setup"); return 1; } size = p.sq_off.array + p.sq_entries * sizeof(unsigned); /* Map the submission queue ring MAP_PRIVATE */ map = mmap(0, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, ring_fd, IORING_OFF_SQ_RING); if (map == MAP_FAILED) { perror("mmap"); return 1; } /* We have at least one page. Let's COW it. */ *map = 0; pause(); return 0; } <--- C reproducer ---> On a system with 16 GiB RAM and swap configured: # ./iouring & # memhog 16G # killall iouring [ 301.552930] ------------[ cut here ]------------ [ 301.553285] WARNING: CPU: 7 PID: 1402 at arch/x86/mm/pat/memtype.c:1060 untrack_pfn+0xf4/0x100 [ 301.553989] Modules linked in: binfmt_misc nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_g [ 301.558232] CPU: 7 PID: 1402 Comm: iouring Not tainted 6.7.5-100.fc38.x86_64 #1 [ 301.558772] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebu4 [ 301.559569] RIP: 0010:untrack_pfn+0xf4/0x100 [ 301.559893] Code: 75 c4 eb cf 48 8b 43 10 8b a8 e8 00 00 00 3b 6b 28 74 b8 48 8b 7b 30 e8 ea 1a f7 000 [ 301.561189] RSP: 0018:ffffba2c0377fab8 EFLAGS: 00010282 [ 301.561590] RAX: 00000000ffffffea RBX: ffff9208c8ce9cc0 RCX: 000000010455e047 [ 301.562105] RDX: 07fffffff0eb1e0a RSI: 0000000000000000 RDI: ffff9208c391d200 [ 301.562628] RBP: 0000000000000000 R08: ffffba2c0377fab8 R09: 0000000000000000 [ 301.563145] R10: ffff9208d2292d50 R11: 0000000000000002 R12: 00007fea890e0000 [ 301.563669] R13: 0000000000000000 R14: ffffba2c0377fc08 R15: 0000000000000000 [ 301.564186] FS: 0000000000000000(0000) GS:ffff920c2fbc0000(0000) knlGS:0000000000000000 [ 301.564773] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 301.565197] CR2: 00007fea88ee8a20 CR3: 00000001033a8000 CR4: 0000000000750ef0 [ 301.565725] PKRU: 55555554 [ 301.565944] Call Trace: [ 301.566148] <TASK> [ 301.566325] ? untrack_pfn+0xf4/0x100 [ 301.566618] ? __warn+0x81/0x130 [ 301.566876] ? untrack_pfn+0xf4/0x100 [ 301.567163] ? report_bug+0x171/0x1a0 [ 301.567466] ? handle_bug+0x3c/0x80 [ 301.567743] ? exc_invalid_op+0x17/0x70 [ 301.568038] ? asm_exc_invalid_op+0x1a/0x20 [ 301.568363] ? untrack_pfn+0xf4/0x100 [ 301.568660] ? untrack_pfn+0x65/0x100 [ 301.568947] unmap_single_vma+0xa6/0xe0 [ 301.569247] unmap_vmas+0xb5/0x190 [ 301.569532] exit_mmap+0xec/0x340 [ 301.569801] __mmput+0x3e/0x130 [ 301.570051] do_exit+0x305/0xaf0 ... Link: https://lkml.kernel.org/r/20240403212131.929421-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reported-by: Wupeng Ma <mawupeng1@huawei.com> Closes: https://lkml.kernel.org/r/20240227122814.3781907-1-mawupeng1@huawei.com Fixes: b1a86e15dc03 ("x86, pat: remove the dependency on 'vm_pgoff' in track/untrack pfn vma routines") Fixes: 5899329b1910 ("x86: PAT: implement track/untrack of pfnmap regions for x86 - v3") Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski35-160/+272
Cross-merge networking fixes after downstream PR. Conflicts: net/ipv4/ip_gre.c 17af420545a7 ("erspan: make sure erspan_base_hdr is present in skb->head") 5832c4a77d69 ("ip_tunnel: convert __be16 tunnel flags to bitmaps") https://lore.kernel.org/all/20240402103253.3b54a1cf@canb.auug.org.au/ Adjacent changes: net/ipv6/ip6_fib.c d21d40605bca ("ipv6: Fix infinite recursion in fib6_dump_done().") 5fc68320c1fb ("ipv6: remove RTNL protection from inet6_dump_fib()") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-05x86/cpufeatures: Add CPUID_LNX_5 to track recently added Linux-defined wordSean Christopherson2-0/+4
Add CPUID_LNX_5 to track cpufeatures' word 21, and add the appropriate compile-time assert in KVM to prevent direct lookups on the features in CPUID_LNX_5. KVM uses X86_FEATURE_* flags to manage guest CPUID, and so must translate features that are scattered by Linux from the Linux-defined bit to the hardware-defined bit, i.e. should never try to directly access scattered features in guest CPUID. Opportunistically add NR_CPUID_WORDS to enum cpuid_leafs, along with a compile-time assert in KVM's CPUID infrastructure to ensure that future additions update cpuid_leafs along with NCAPINTS. No functional change intended. Fixes: 7f274e609f3d ("x86/cpufeatures: Add new word for scattered features") Cc: Sandipan Das <sandipan.das@amd.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-04-05Merge tag 'net-6.9-rc3' of ↵Linus Torvalds3-15/+12
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from netfilter, bluetooth and bpf. Fairly usual collection of driver and core fixes. The large selftest accompanying one of the fixes is also becoming a common occurrence. Current release - regressions: - ipv6: fix infinite recursion in fib6_dump_done() - net/rds: fix possible null-deref in newly added error path Current release - new code bugs: - net: do not consume a full cacheline for system_page_pool - bpf: fix bpf_arena-related file descriptor leaks in the verifier - drv: ice: fix freeing uninitialized pointers, fixing misuse of the newfangled __free() auto-cleanup Previous releases - regressions: - x86/bpf: fixes the BPF JIT with retbleed=stuff - xen-netfront: add missing skb_mark_for_recycle, fix page pool accounting leaks, revealed by recently added explicit warning - tcp: fix bind() regression for v6-only wildcard and v4-mapped-v6 non-wildcard addresses - Bluetooth: - replace "hci_qca: Set BDA quirk bit if fwnode exists in DT" with better workarounds to un-break some buggy Qualcomm devices - set conn encrypted before conn establishes, fix re-connecting to some headsets which use slightly unusual sequence of msgs - mptcp: - prevent BPF accessing lowat from a subflow socket - don't account accept() of non-MPC client as fallback to TCP - drv: mana: fix Rx DMA datasize and skb_over_panic - drv: i40e: fix VF MAC filter removal Previous releases - always broken: - gro: various fixes related to UDP tunnels - netns crossing problems, incorrect checksum conversions, and incorrect packet transformations which may lead to panics - bpf: support deferring bpf_link dealloc to after RCU grace period - nf_tables: - release batch on table validation from abort path - release mutex after nft_gc_seq_end from abort path - flush pending destroy work before exit_net release - drv: r8169: skip DASH fw status checks when DASH is disabled" * tag 'net-6.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (81 commits) netfilter: validate user input for expected length net/sched: act_skbmod: prevent kernel-infoleak net: usb: ax88179_178a: avoid the interface always configured as random address net: dsa: sja1105: Fix parameters order in sja1110_pcs_mdio_write_c45() net: ravb: Always update error counters net: ravb: Always process TX descriptor ring netfilter: nf_tables: discard table flag update with pending basechain deletion netfilter: nf_tables: Fix potential data-race in __nft_flowtable_type_get() netfilter: nf_tables: reject new basechain after table flag update netfilter: nf_tables: flush pending destroy work before exit_net release netfilter: nf_tables: release mutex after nft_gc_seq_end from abort path netfilter: nf_tables: release batch on table validation from abort path Revert "tg3: Remove residual error handling in tg3_suspend" tg3: Remove residual error handling in tg3_suspend net: mana: Fix Rx DMA datasize and skb_over_panic net/sched: fix lockdep splat in qdisc_tree_reduce_backlog() net: phy: micrel: lan8814: Fix when enabling/disabling 1-step timestamping net: stmmac: fix rx queue priority assignment net: txgbe: fix i2c dev name cannot match clkdev net: fec: Set mac_managed_pm during probe ...
2024-04-04x86/mce: Make sure to grab mce_sysfs_mutex in set_bank()Borislav Petkov (AMD)1-1/+3
Modifying a MCA bank's MCA_CTL bits which control which error types to be reported is done over /sys/devices/system/machinecheck/ ├── machinecheck0 │   ├── bank0 │   ├── bank1 │   ├── bank10 │   ├── bank11 ... sysfs nodes by writing the new bit mask of events to enable. When the write is accepted, the kernel deletes all current timers and reinits all banks. Doing that in parallel can lead to initializing a timer which is already armed and in the timer wheel, i.e., in use already: ODEBUG: init active (active state 0) object: ffff888063a28000 object type: timer_list hint: mce_timer_fn+0x0/0x240 arch/x86/kernel/cpu/mce/core.c:2642 WARNING: CPU: 0 PID: 8120 at lib/debugobjects.c:514 debug_print_object+0x1a0/0x2a0 lib/debugobjects.c:514 Fix that by grabbing the sysfs mutex as the rest of the MCA sysfs code does. Reported by: Yue Sun <samsun1006219@gmail.com> Reported by: xingwei lee <xrivendell7@gmail.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/CAEkJfYNiENwQY8yV1LYJ9LjJs%2Bx_-PqMv98gKig55=2vbzffRw@mail.gmail.com
2024-04-04x86/CPU/AMD: Track SNP host status with cc_platform_*()Borislav Petkov (AMD)6-37/+45
The host SNP worthiness can determined later, after alternatives have been patched, in snp_rmptable_init() depending on cmdline options like iommu=pt which is incompatible with SNP, for example. Which means that one cannot use X86_FEATURE_SEV_SNP and will need to have a special flag for that control. Use that newly added CC_ATTR_HOST_SEV_SNP in the appropriate places. Move kdump_sev_callback() to its rightful place, while at it. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Srikanth Aithal <sraithal@amd.com> Link: https://lore.kernel.org/r/20240327154317.29909-6-bp@alien8.de
2024-04-04x86/cc: Add cc_platform_set/_clear() helpersBorislav Petkov (AMD)1-0/+52
Add functionality to set and/or clear different attributes of the machine as a confidential computing platform. Add the first one too: whether the machine is running as a host for SEV-SNP guests. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Srikanth Aithal <sraithal@amd.com> Link: https://lore.kernel.org/r/20240327154317.29909-5-bp@alien8.de
2024-04-04x86/kvm/Kconfig: Have KVM_AMD_SEV select ARCH_HAS_CC_PLATFORMBorislav Petkov (AMD)1-0/+1
The functionality to load SEV-SNP guests by the host will soon rely on cc_platform* helpers because the cpu_feature* API with the early patching is insufficient when SNP support needs to be disabled late. Therefore, pull that functionality in. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Srikanth Aithal <sraithal@amd.com> Link: https://lore.kernel.org/r/20240327154317.29909-4-bp@alien8.de
2024-04-04x86/coco: Require seeding RNG with RDRAND on CoCo systemsJason A. Donenfeld3-0/+45
There are few uses of CoCo that don't rely on working cryptography and hence a working RNG. Unfortunately, the CoCo threat model means that the VM host cannot be trusted and may actively work against guests to extract secrets or manipulate computation. Since a malicious host can modify or observe nearly all inputs to guests, the only remaining source of entropy for CoCo guests is RDRAND. If RDRAND is broken -- due to CPU hardware fault -- the RNG as a whole is meant to gracefully continue on gathering entropy from other sources, but since there aren't other sources on CoCo, this is catastrophic. This is mostly a concern at boot time when initially seeding the RNG, as after that the consequences of a broken RDRAND are much more theoretical. So, try at boot to seed the RNG using 256 bits of RDRAND output. If this fails, panic(). This will also trigger if the system is booted without RDRAND, as RDRAND is essential for a safe CoCo boot. Add this deliberately to be "just a CoCo x86 driver feature" and not part of the RNG itself. Many device drivers and platforms have some desire to contribute something to the RNG, and add_device_randomness() is specifically meant for this purpose. Any driver can call it with seed data of any quality, or even garbage quality, and it can only possibly make the quality of the RNG better or have no effect, but can never make it worse. Rather than trying to build something into the core of the RNG, consider the particular CoCo issue just a CoCo issue, and therefore separate it all out into driver (well, arch/platform) code. [ bp: Massage commit message. ] Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Elena Reshetova <elena.reshetova@intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240326160735.73531-1-Jason@zx2c4.com
2024-04-04x86/numa/32: Include missing <asm/pgtable_areas.h>Arnd Bergmann1-0/+1
The __vmalloc_start_set declaration is in a header that is not included in numa_32.c in current linux-next: arch/x86/mm/numa_32.c: In function 'initmem_init': arch/x86/mm/numa_32.c:57:9: error: '__vmalloc_start_set' undeclared (first use in this function) 57 | __vmalloc_start_set = true; | ^~~~~~~~~~~~~~~~~~~ arch/x86/mm/numa_32.c:57:9: note: each undeclared identifier is reported only once for each function it appears in Add an explicit #include. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20240403202344.3463169-1-arnd@kernel.org
2024-04-03Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds6-51/+94
Pull KVM fixes from Paolo Bonzini: "ARM: - Ensure perf events programmed to count during guest execution are actually enabled before entering the guest in the nVHE configuration - Restore out-of-range handler for stage-2 translation faults - Several fixes to stage-2 TLB invalidations to avoid stale translations, possibly including partial walk caches - Fix early handling of architectural VHE-only systems to ensure E2H is appropriately set - Correct a format specifier warning in the arch_timer selftest - Make the KVM banner message correctly handle all of the possible configurations RISC-V: - Remove redundant semicolon in num_isa_ext_regs() - Fix APLIC setipnum_le/be write emulation - Fix APLIC in_clrip[x] read emulation x86: - Fix a bug in KVM_SET_CPUID{2,} where KVM looks at the wrong CPUID entries (old vs. new) and ultimately neglects to clear PV_UNHALT from vCPUs with HLT-exiting disabled - Documentation fixes for SEV - Fix compat ABI for KVM_MEMORY_ENCRYPT_OP - Fix a 14-year-old goof in a declaration shared by host and guest; the enabled field used by Linux when running as a guest pushes the size of "struct kvm_vcpu_pv_apf_data" from 64 to 68 bytes. This is really unconsequential because KVM never consumes anything beyond the first 64 bytes, but the resulting struct does not match the documentation Selftests: - Fix spelling mistake in arch_timer selftest" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (25 commits) KVM: arm64: Rationalise KVM banner output arm64: Fix early handling of FEAT_E2H0 not being implemented KVM: arm64: Ensure target address is granule-aligned for range TLBI KVM: arm64: Use TLBI_TTL_UNKNOWN in __kvm_tlb_flush_vmid_range() KVM: arm64: Don't pass a TLBI level hint when zapping table entries KVM: arm64: Don't defer TLB invalidation when zapping table entries KVM: selftests: Fix __GUEST_ASSERT() format warnings in ARM's arch timer test KVM: arm64: Fix out-of-IPA space translation fault handling KVM: arm64: Fix host-programmed guest events in nVHE RISC-V: KVM: Fix APLIC in_clrip[x] read emulation RISC-V: KVM: Fix APLIC setipnum_le/be write emulation RISC-V: KVM: Remove second semicolon KVM: selftests: Fix spelling mistake "trigged" -> "triggered" Documentation: kvm/sev: clarify usage of KVM_MEMORY_ENCRYPT_OP Documentation: kvm/sev: separate description of firmware KVM: SEV: fix compat ABI for KVM_MEMORY_ENCRYPT_OP KVM: selftests: Check that PV_UNHALT is cleared when HLT exiting is disabled KVM: x86: Use actual kvm_cpuid.base for clearing KVM_FEATURE_PV_UNHALT KVM: x86: Introduce __kvm_get_hypervisor_cpuid() helper KVM: SVM: Return -EINVAL instead of -EBUSY on attempt to re-init SEV/SEV-ES ...
2024-04-03x86/retpoline: Do the necessary fixup to the Zen3/4 srso return thunk for !SRSOBorislav Petkov (AMD)1-1/+4
The srso_alias_untrain_ret() dummy thunk in the !CONFIG_MITIGATION_SRSO case is there only for the altenative in CALL_UNTRAIN_RET to have a symbol to resolve. However, testing with kernels which don't have CONFIG_MITIGATION_SRSO enabled, leads to the warning in patch_return() to fire: missing return thunk: srso_alias_untrain_ret+0x0/0x10-0x0: eb 0e 66 66 2e WARNING: CPU: 0 PID: 0 at arch/x86/kernel/alternative.c:826 apply_returns (arch/x86/kernel/alternative.c:826 Put in a plain "ret" there so that gcc doesn't put a return thunk in in its place which special and gets checked. In addition: ERROR: modpost: "srso_alias_untrain_ret" [arch/x86/kvm/kvm-amd.ko] undefined! make[2]: *** [scripts/Makefile.modpost:145: Module.symvers] Chyba 1 make[1]: *** [/usr/src/linux-6.8.3/Makefile:1873: modpost] Chyba 2 make: *** [Makefile:240: __sub-make] Chyba 2 since !SRSO builds would use the dummy return thunk as reported by petr.pisar@atlas.cz, https://bugzilla.kernel.org/show_bug.cgi?id=218679. Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202404020901.da75a60f-oliver.sang@intel.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/all/202404020901.da75a60f-oliver.sang@intel.com/ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-04-03perf/x86/intel/ds: Don't clear ->pebs_data_cfg for the last PEBS eventKan Liang1-4/+4
The MSR_PEBS_DATA_CFG MSR register is used to configure which data groups should be generated into a PEBS record, and it's shared among all counters. If there are different configurations among counters, perf combines all the configurations. The first perf command as below requires a complete PEBS record (including memory info, GPRs, XMMs, and LBRs). The second perf command only requires a basic group. However, after the second perf command is running, the MSR_PEBS_DATA_CFG register is cleared. Only a basic group is generated in a PEBS record, which is wrong. The required information for the first perf command is missed. $ perf record --intr-regs=AX,SP,XMM0 -a -C 8 -b -W -d -c 100000003 -o /dev/null -e cpu/event=0xd0,umask=0x81/upp & $ sleep 5 $ perf record --per-thread -c 1 -e cycles:pp --no-timestamp --no-tid taskset -c 8 ./noploop 1000 The first PEBS event is a system-wide PEBS event. The second PEBS event is a per-thread event. When the thread is scheduled out, the intel_pmu_pebs_del() function is invoked to update the PEBS state. Since the system-wide event is still available, the cpuc->n_pebs is 1. The cpuc->pebs_data_cfg is cleared. The data configuration for the system-wide PEBS event is lost. The (cpuc->n_pebs == 1) check was introduced in commit: b6a32f023fcc ("perf/x86: Fix PEBS threshold initialization") At that time, it indeed didn't hurt whether the state was updated during the removal, because only the threshold is updated. The calculation of the threshold takes the last PEBS event into account. However, since commit: b752ea0c28e3 ("perf/x86/intel/ds: Flush PEBS DS when changing PEBS_DATA_CFG") we delay the threshold update, and clear the PEBS data config, which triggers the bug. The PEBS data config update scope should not be shrunk during removal. [ mingo: Improved the changelog & comments. ] Fixes: b752ea0c28e3 ("perf/x86/intel/ds: Flush PEBS DS when changing PEBS_DATA_CFG") Reported-by: Stephane Eranian <eranian@google.com> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240401133320.703971-1-kan.liang@linux.intel.com
2024-04-03x86/resctrl: Fix uninitialized memory read when last CPU of domain goes offlineReinette Chatre1-1/+2
Tony encountered this OOPS when the last CPU of a domain goes offline while running a kernel built with CONFIG_NO_HZ_FULL: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 Oops: 0000 [#1] PREEMPT SMP NOPTI ... RIP: 0010:__find_nth_andnot_bit+0x66/0x110 ... Call Trace: <TASK> ? __die() ? page_fault_oops() ? exc_page_fault() ? asm_exc_page_fault() cpumask_any_housekeeping() mbm_setup_overflow_handler() resctrl_offline_cpu() resctrl_arch_offline_cpu() cpuhp_invoke_callback() cpuhp_thread_fun() smpboot_thread_fn() kthread() ret_from_fork() ret_from_fork_asm() </TASK> The NULL pointer dereference is encountered while searching for another online CPU in the domain (of which there are none) that can be used to run the MBM overflow handler. Because the kernel is configured with CONFIG_NO_HZ_FULL the search for another CPU (in its effort to prefer those CPUs that aren't marked nohz_full) consults the mask representing the nohz_full CPUs, tick_nohz_full_mask. On a kernel with CONFIG_CPUMASK_OFFSTACK=y tick_nohz_full_mask is not allocated unless the kernel is booted with the "nohz_full=" parameter and because of that any access to tick_nohz_full_mask needs to be guarded with tick_nohz_full_enabled(). Replace the IS_ENABLED(CONFIG_NO_HZ_FULL) with tick_nohz_full_enabled(). The latter ensures tick_nohz_full_mask can be accessed safely and can be used whether kernel is built with CONFIG_NO_HZ_FULL enabled or not. [ Use Ingo's suggestion that combines the two NO_HZ checks into one. ] Fixes: a4846aaf3945 ("x86/resctrl: Add cpumask_any_housekeeping() for limbo/overflow") Reported-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/ff8dfc8d3dcb04b236d523d1e0de13d2ef585223.1711993956.git.reinette.chatre@intel.com Closes: https://lore.kernel.org/lkml/ZgIFT5gZgIQ9A9G7@agluck-desk3/
2024-04-02Merge tag 'kvmarm-fixes-6.9-1' of ↵Paolo Bonzini32-277/+369
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.9, part #1 - Ensure perf events programmed to count during guest execution are actually enabled before entering the guest in the nVHE configuration. - Restore out-of-range handler for stage-2 translation faults. - Several fixes to stage-2 TLB invalidations to avoid stale translations, possibly including partial walk caches. - Fix early handling of architectural VHE-only systems to ensure E2H is appropriately set. - Correct a format specifier warning in the arch_timer selftest. - Make the KVM banner message correctly handle all of the possible configurations.
2024-04-02x86/bpf: Fix IP for relocating call depth accountingJoan Bruguera Micó3-15/+12
The commit: 59bec00ace28 ("x86/percpu: Introduce %rip-relative addressing to PER_CPU_VAR()") made PER_CPU_VAR() to use rip-relative addressing, hence INCREMENT_CALL_DEPTH macro and skl_call_thunk_template got rip-relative asm code inside of it. A follow up commit: 17bce3b2ae2d ("x86/callthunks: Handle %rip-relative relocations in call thunk template") changed x86_call_depth_emit_accounting() to use apply_relocation(), but mistakenly assumed that the code is being patched in-place (where the destination of the relocation matches the address of the code), using *pprog as the destination ip. This is not true for the call depth accounting, emitted by the BPF JIT, so the calculated address was wrong, JIT-ed BPF progs on kernels with call depth tracking got broken and usually caused a page fault. Pass the destination IP when the BPF JIT emits call depth accounting. Fixes: 17bce3b2ae2d ("x86/callthunks: Handle %rip-relative relocations in call thunk template") Signed-off-by: Joan Bruguera Micó <joanbrugueram@gmail.com> Reviewed-by: Uros Bizjak <ubizjak@gmail.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20240401185821.224068-3-ubizjak@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-04-02x86/bpf: Fix IP after emitting call depth accountingUros Bizjak1-1/+1
Adjust the IP passed to `emit_patch` so it calculates the correct offset for the CALL instruction if `x86_call_depth_emit_accounting` emits code. Otherwise we will skip some instructions and most likely crash. Fixes: b2e9dfe54be4 ("x86/bpf: Emit call depth accounting if required") Link: https://lore.kernel.org/lkml/20230105214922.250473-1-joanbrugueram@gmail.com/ Co-developed-by: Joan Bruguera Micó <joanbrugueram@gmail.com> Signed-off-by: Joan Bruguera Micó <joanbrugueram@gmail.com> Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20240401185821.224068-2-ubizjak@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>