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2024-04-10x86/bhi: Mitigate KVM by defaultPawan Gupta2-4/+8
commit 95a6ccbdc7199a14b71ad8901cb788ba7fb5167b upstream. 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> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10x86/bhi: Add BHI mitigation knobPawan Gupta2-6/+50
commit ec9404e40e8f36421a2b66ecb76dc2209fe7f3ef upstream. 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> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03x86/cpu: Enable STIBP on AMD if Automatic IBRS is enabledKim Phillips1-4/+7
commit fd470a8beed88440b160d690344fbae05a0b9b1b upstream. Unlike Intel's Enhanced IBRS feature, AMD's Automatic IBRS does not provide protection to processes running at CPL3/user mode, see section "Extended Feature Enable Register (EFER)" in the APM v2 at https://bugzilla.kernel.org/attachment.cgi?id=304652 Explicitly enable STIBP to protect against cross-thread CPL3 branch target injections on systems with Automatic IBRS enabled. Also update the relevant documentation. Fixes: e7862eda309e ("x86/cpu: Support AMD Automatic IBRS") Reported-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230720194727.67022-1-kim.phillips@amd.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03x86/Kconfig: Remove CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULTBorislav Petkov (AMD)1-3/+1
commit 29956748339aa8757a7e2f927a8679dd08f24bb6 upstream. It was meant well at the time but nothing's using it so get rid of it. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240202163510.GDZb0Zvj8qOndvFOiZ@fat_crate.local Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03x86/cpu: Support AMD Automatic IBRSKim Phillips2-6/+6
commit e7862eda309ecfccc36bb5558d937ed3ace07f3f upstream. The AMD Zen4 core supports a new feature called Automatic IBRS. It is a "set-and-forget" feature that means that, like Intel's Enhanced IBRS, h/w manages its IBRS mitigation resources automatically across CPL transitions. The feature is advertised by CPUID_Fn80000021_EAX bit 8 and is enabled by setting MSR C000_0080 (EFER) bit 21. Enable Automatic IBRS by default if the CPU feature is present. It typically provides greater performance over the incumbent generic retpolines mitigation. Reuse the SPECTRE_V2_EIBRS spectre_v2_mitigation enum. AMD Automatic IBRS and Intel Enhanced IBRS have similar enablement. Add NO_EIBRS_PBRSB to cpu_vuln_whitelist, since AMD Automatic IBRS isn't affected by PBRSB-eIBRS. The kernel command line option spectre_v2=eibrs is used to select AMD Automatic IBRS, if available. Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Sean Christopherson <seanjc@google.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/r/20230124163319.2277355-8-kim.phillips@amd.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-15x86/rfds: Mitigate Register File Data Sampling (RFDS)Pawan Gupta1-0/+21
commit 8076fcde016c9c0e0660543e67bff86cb48a7c9c upstream. RFDS is a CPU vulnerability that may allow userspace to infer kernel stale data previously used in floating point registers, vector registers and integer registers. RFDS only affects certain Intel Atom processors. Intel released a microcode update that uses VERW instruction to clear the affected CPU buffers. Unlike MDS, none of the affected cores support SMT. Add RFDS bug infrastructure and enable the VERW based mitigation by default, that clears the affected buffers just before exiting to userspace. Also add sysfs reporting and cmdline parameter "reg_file_data_sampling" to control the mitigation. For details see: Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-15Documentation/hw-vuln: Add documentation for RFDSPawan Gupta2-0/+105
commit 4e42765d1be01111df0c0275bbaf1db1acef346e upstream. Add the documentation for transient execution vulnerability Register File Data Sampling (RFDS) that affects Intel Atom CPUs. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-01docs: kernel_abi.py: fix command injectionVegard Nossum4-4/+4
commit 3231dd5862779c2e15633c96133a53205ad660ce upstream. The kernel-abi directive passes its argument straight to the shell. This is unfortunate and unnecessary. Let's always use paths relative to $srctree/Documentation/ and use subprocess.check_call() instead of subprocess.Popen(shell=True). This also makes the code shorter. Link: https://fosstodon.org/@jani/111676532203641247 Reported-by: Jani Nikula <jani.nikula@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20231231235959.3342928-2-vegard.nossum@oracle.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28smp,csd: Throw an error if a CSD lock is stuck for too longRik van Riel1-0/+7
[ Upstream commit 94b3f0b5af2c7af69e3d6e0cdd9b0ea535f22186 ] The CSD lock seems to get stuck in 2 "modes". When it gets stuck temporarily, it usually gets released in a few seconds, and sometimes up to one or two minutes. If the CSD lock stays stuck for more than several minutes, it never seems to get unstuck, and gradually more and more things in the system end up also getting stuck. In the latter case, we should just give up, so the system can dump out a little more information about what went wrong, and, with panic_on_oops and a kdump kernel loaded, dump a whole bunch more information about what might have gone wrong. In addition, there is an smp.panic_on_ipistall kernel boot parameter that by default retains the old behavior, but when set enables the panic after the CSD lock has been stuck for more than the specified number of milliseconds, as in 300,000 for five minutes. [ paulmck: Apply Imran Khan feedback. ] [ paulmck: Apply Leonardo Bras feedback. ] Link: https://lore.kernel.org/lkml/bc7cc8b0-f587-4451-8bcd-0daae627bcc7@paulmck-laptop/ Signed-off-by: Rik van Riel <riel@surriel.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Imran Khan <imran.f.khan@oracle.com> Reviewed-by: Leonardo Bras <leobras@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06mm, memcg: reconsider kmem.limit_in_bytes deprecationMichal Hocko1-0/+7
commit 4597648fddeadef5877610d693af11906aa666ac upstream. This reverts commits 86327e8eb94c ("memcg: drop kmem.limit_in_bytes") and partially reverts 58056f77502f ("memcg, kmem: further deprecate kmem.limit_in_bytes") which have incrementally removed support for the kernel memory accounting hard limit. Unfortunately it has turned out that there is still userspace depending on the existence of memory.kmem.limit_in_bytes [1]. The underlying functionality is not really required but the non-existent file just confuses the userspace which fails in the result. The patch to fix this on the userspace side has been submitted but it is hard to predict how it will propagate through the maze of 3rd party consumers of the software. Now, reverting alone 86327e8eb94c is not an option because there is another set of userspace which cannot cope with ENOTSUPP returned when writing to the file. Therefore we have to go and revisit 58056f77502f as well. There are two ways to go ahead. Either we give up on the deprecation and fully revert 58056f77502f as well or we can keep kmem.limit_in_bytes but make the write a noop and warn about the fact. This should work for both known breaking workloads which depend on the existence but do not depend on the hard limit enforcement. Note to backporters to stable trees. a8c49af3be5f ("memcg: add per-memcg total kernel memory stat") introduced in 4.18 has added memcg_account_kmem so the accounting is not done by obj_cgroup_charge_pages directly for v1 anymore. Prior kernels need to add it explicitly (thanks to Johannes for pointing this out). [akpm@linux-foundation.org: fix build - remove unused local] Link: http://lkml.kernel.org/r/20230920081101.GA12096@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net [1] Link: https://lkml.kernel.org/r/ZRE5VJozPZt9bRPy@dhcp22.suse.cz Fixes: 86327e8eb94c ("memcg: drop kmem.limit_in_bytes") Fixes: 58056f77502f ("memcg, kmem: further deprecate kmem.limit_in_bytes") Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Shakeel Butt <shakeelb@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jeremi Piotrowski <jpiotrowski@linux.microsoft.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Tejun heo <tj@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-06memcg: drop kmem.limit_in_bytesMichal Hocko1-2/+0
commit 86327e8eb94c52eca4f93cfece2e29d1bf52acbf upstream. kmem.limit_in_bytes (v1 way to limit kernel memory usage) has been deprecated since 58056f77502f ("memcg, kmem: further deprecate kmem.limit_in_bytes") merged in 5.16. We haven't heard about any serious users since then but it seems that the mere presence of the file is causing more harm thatn good. We (SUSE) have had several bug reports from customers where Docker based containers started to fail because a write to kmem.limit_in_bytes has failed. This was unexpected because runc code only expects ENOENT (kmem disabled) or EBUSY (tasks already running within cgroup). So a new error code was unexpected and the whole container startup failed. This has been later addressed by https://github.com/opencontainers/runc/commit/52390d68040637dfc77f9fda6bbe70952423d380 so current Docker runtimes do not suffer from the problem anymore. There are still older version of Docker in use and likely hard to get rid of completely. Address this by wiping out the file completely and effectively get back to pre 4.5 era and CONFIG_MEMCG_KMEM=n configuration. I would recommend backporting to stable trees which have picked up 58056f77502f ("memcg, kmem: further deprecate kmem.limit_in_bytes"). [mhocko@suse.com: restore _KMEM switch case] Link: https://lkml.kernel.org/r/ZKe5wxdbvPi5Cwd7@dhcp22.suse.cz Link: https://lkml.kernel.org/r/20230704115240.14672-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Shakeel Butt <shakeelb@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-23Revert "memcg: drop kmem.limit_in_bytes"Greg Kroah-Hartman1-0/+2
This reverts commit 21ef9e11205fca43785eecf7d4a99528d4de5701 which is commit 86327e8eb94c52eca4f93cfece2e29d1bf52acbf upstream. It breaks existing runc systems, as the tool always thinks the file should be present. Reported-by: Jeremi Piotrowski <jpiotrowski@linux.microsoft.com> Link: https://lore.kernel.org/r/20230920081101.GA12096@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net Cc: Michal Hocko <mhocko@suse.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-19memcg: drop kmem.limit_in_bytesMichal Hocko1-2/+0
commit 86327e8eb94c52eca4f93cfece2e29d1bf52acbf upstream. kmem.limit_in_bytes (v1 way to limit kernel memory usage) has been deprecated since 58056f77502f ("memcg, kmem: further deprecate kmem.limit_in_bytes") merged in 5.16. We haven't heard about any serious users since then but it seems that the mere presence of the file is causing more harm thatn good. We (SUSE) have had several bug reports from customers where Docker based containers started to fail because a write to kmem.limit_in_bytes has failed. This was unexpected because runc code only expects ENOENT (kmem disabled) or EBUSY (tasks already running within cgroup). So a new error code was unexpected and the whole container startup failed. This has been later addressed by https://github.com/opencontainers/runc/commit/52390d68040637dfc77f9fda6bbe70952423d380 so current Docker runtimes do not suffer from the problem anymore. There are still older version of Docker in use and likely hard to get rid of completely. Address this by wiping out the file completely and effectively get back to pre 4.5 era and CONFIG_MEMCG_KMEM=n configuration. I would recommend backporting to stable trees which have picked up 58056f77502f ("memcg, kmem: further deprecate kmem.limit_in_bytes"). [mhocko@suse.com: restore _KMEM switch case] Link: https://lkml.kernel.org/r/ZKe5wxdbvPi5Cwd7@dhcp22.suse.cz Link: https://lkml.kernel.org/r/20230704115240.14672-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Shakeel Butt <shakeelb@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-02ACPI: thermal: Drop nocrt parameterMario Limonciello1-4/+0
commit 5f641174a12b8a876a4101201a21ef4675ecc014 upstream. The `nocrt` module parameter has no code associated with it and does nothing. As `crt=-1` has same functionality as what nocrt should be doing drop `nocrt` and associated documentation. This should fix a quirk for Gigabyte GA-7ZX that used `nocrt` and thus didn't function properly. Fixes: 8c99fdce3078 ("ACPI: thermal: set "thermal.nocrt" via DMI on Gigabyte GA-7ZX") Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Cc: All applicable <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-26x86/cpu: Rename srso_(.*)_alias to srso_alias_\1Peter Zijlstra1-2/+2
commit 42be649dd1f2eee6b1fb185f1a231b9494cf095f upstream. For a more consistent namespace. [ bp: Fixup names in the doc too. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230814121148.976236447@infradead.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23iommu/amd: Introduce Disable IRTE Caching SupportSuravee Suthikulpanit1-0/+1
[ Upstream commit 66419036f68a838c00cbccacd6cb2e99da6e5710 ] An Interrupt Remapping Table (IRT) stores interrupt remapping configuration for each device. In a normal operation, the AMD IOMMU caches the table to optimize subsequent data accesses. This requires the IOMMU driver to invalidate IRT whenever it updates the table. The invalidation process includes issuing an INVALIDATE_INTERRUPT_TABLE command following by a COMPLETION_WAIT command. However, there are cases in which the IRT is updated at a high rate. For example, for IOMMU AVIC, the IRTE[IsRun] bit is updated on every vcpu scheduling (i.e. amd_iommu_update_ga()). On system with large amount of vcpus and VFIO PCI pass-through devices, the invalidation process could potentially become a performance bottleneck. Introducing a new kernel boot option: amd_iommu=irtcachedis which disables IRTE caching by setting the IRTCachedis bit in each IOMMU Control register, and bypass the IRT invalidation process. Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com> Co-developed-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com> Signed-off-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Link: https://lore.kernel.org/r/20230530141137.14376-4-suravee.suthikulpanit@amd.com Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-08x86/srso: Add a Speculative RAS Overflow mitigationBorislav Petkov (AMD)3-0/+145
Upstream commit: fb3bd914b3ec28f5fb697ac55c4846ac2d542855 Add a mitigation for the speculative return address stack overflow vulnerability found on AMD processors. The mitigation works by ensuring all RET instructions speculate to a controlled location, similar to how speculation is controlled in the retpoline sequence. To accomplish this, the __x86_return_thunk forces the CPU to mispredict every function return using a 'safe return' sequence. To ensure the safety of this mitigation, the kernel must ensure that the safe return sequence is itself free from attacker interference. In Zen3 and Zen4, this is accomplished by creating a BTB alias between the untraining function srso_untrain_ret_alias() and the safe return function srso_safe_ret_alias() which results in evicting a potentially poisoned BTB entry and using that safe one for all function returns. In older Zen1 and Zen2, this is accomplished using a reinterpretation technique similar to Retbleed one: srso_untrain_ret() and srso_safe_ret(). Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-08Documentation/x86: Fix backwards on/off logic about YMM supportDave Hansen1-1/+1
commit 1b0fc0345f2852ffe54fb9ae0e12e2ee69ad6a20 upstream These options clearly turn *off* XSAVE YMM support. Correct the typo. Reported-by: Ben Hutchings <ben@decadent.org.uk> Fixes: 553a5c03e90a ("x86/speculation: Add force option to GDS mitigation") Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-08x86/speculation: Add force option to GDS mitigationDaniel Sneddon2-5/+21
commit 553a5c03e90a6087e88f8ff878335ef0621536fb upstream The Gather Data Sampling (GDS) vulnerability allows malicious software to infer stale data previously stored in vector registers. This may include sensitive data such as cryptographic keys. GDS is mitigated in microcode, and systems with up-to-date microcode are protected by default. However, any affected system that is running with older microcode will still be vulnerable to GDS attacks. Since the gather instructions used by the attacker are part of the AVX2 and AVX512 extensions, disabling these extensions prevents gather instructions from being executed, thereby mitigating the system from GDS. Disabling AVX2 is sufficient, but we don't have the granularity to do this. The XCR0[2] disables AVX, with no option to just disable AVX2. Add a kernel parameter gather_data_sampling=force that will enable the microcode mitigation if available, otherwise it will disable AVX on affected systems. This option will be ignored if cmdline mitigations=off. This is a *big* hammer. It is known to break buggy userspace that uses incomplete, buggy AVX enumeration. Unfortunately, such userspace does exist in the wild: https://www.mail-archive.com/bug-coreutils@gnu.org/msg33046.html [ dhansen: add some more ominous warnings about disabling AVX ] Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-08x86/speculation: Add Gather Data Sampling mitigationDaniel Sneddon3-13/+128
commit 8974eb588283b7d44a7c91fa09fcbaf380339f3a upstream Gather Data Sampling (GDS) is a hardware vulnerability which allows unprivileged speculative access to data which was previously stored in vector registers. Intel processors that support AVX2 and AVX512 have gather instructions that fetch non-contiguous data elements from memory. On vulnerable hardware, when a gather instruction is transiently executed and encounters a fault, stale data from architectural or internal vector registers may get transiently stored to the destination vector register allowing an attacker to infer the stale data using typical side channel techniques like cache timing attacks. This mitigation is different from many earlier ones for two reasons. First, it is enabled by default and a bit must be set to *DISABLE* it. This is the opposite of normal mitigation polarity. This means GDS can be mitigated simply by updating microcode and leaving the new control bit alone. Second, GDS has a "lock" bit. This lock bit is there because the mitigation affects the hardware security features KeyLocker and SGX. It needs to be enabled and *STAY* enabled for these features to be mitigated against GDS. The mitigation is enabled in the microcode by default. Disable it by setting gather_data_sampling=off or by disabling all mitigations with mitigations=off. The mitigation status can be checked by reading: /sys/devices/system/cpu/vulnerabilities/gather_data_sampling Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-03Documentation: security-bugs.rst: clarify CVE handlingGreg Kroah-Hartman1-7/+6
commit 3c1897ae4b6bc7cc586eda2feaa2cd68325ec29c upstream. The kernel security team does NOT assign CVEs, so document that properly and provide the "if you want one, ask MITRE for it" response that we give on a weekly basis in the document, so we don't have to constantly say it to everyone who asks. Link: https://lore.kernel.org/r/2023063022-retouch-kerosene-7e4a@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-03Documentation: security-bugs.rst: update preferences when dealing with the ↵Greg Kroah-Hartman1-14/+12
linux-distros group commit 4fee0915e649bd0cea56dece6d96f8f4643df33c upstream. Because the linux-distros group forces reporters to release information about reported bugs, and they impose arbitrary deadlines in having those bugs fixed despite not actually being kernel developers, the kernel security team recommends not interacting with them at all as this just causes confusion and the early-release of reported security problems. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/2023063020-throat-pantyhose-f110@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-23dm init: add dm-mod.waitfor to wait for asynchronously probed block devicesPeter Korsgaard1-0/+8
commit 035641b01e72af4f6c6cf22a4bdb5d7dfc4e8e8e upstream. Just calling wait_for_device_probe() is not enough to ensure that asynchronously probed block devices are available (E.G. mmc, usb), so add a "dm-mod.waitfor=<device1>[,..,<deviceN>]" parameter to get dm-init to explicitly wait for specific block devices before initializing the tables with logic similar to the rootwait logic that was introduced with commit cc1ed7542c8c ("init: wait for asynchronously scanned block devices"). E.G. with dm-verity on mmc using: dm-mod.waitfor="PARTLABEL=hash-a,PARTLABEL=root-a" [ 0.671671] device-mapper: init: waiting for all devices to be available before creating mapped devices [ 0.671679] device-mapper: init: waiting for device PARTLABEL=hash-a ... [ 0.710695] mmc0: new HS200 MMC card at address 0001 [ 0.711158] mmcblk0: mmc0:0001 004GA0 3.69 GiB [ 0.715954] mmcblk0boot0: mmc0:0001 004GA0 partition 1 2.00 MiB [ 0.722085] mmcblk0boot1: mmc0:0001 004GA0 partition 2 2.00 MiB [ 0.728093] mmcblk0rpmb: mmc0:0001 004GA0 partition 3 512 KiB, chardev (249:0) [ 0.738274] mmcblk0: p1 p2 p3 p4 p5 p6 p7 [ 0.751282] device-mapper: init: waiting for device PARTLABEL=root-a ... [ 0.751306] device-mapper: init: all devices available [ 0.751683] device-mapper: verity: sha256 using implementation "sha256-generic" [ 0.759344] device-mapper: ioctl: dm-0 (vroot) is ready [ 0.766540] VFS: Mounted root (squashfs filesystem) readonly on device 254:0. Signed-off-by: Peter Korsgaard <peter@korsgaard.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org> Cc: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-10mm: memcontrol: deprecate charge movingJohannes Weiner1-2/+11
commit da34a8484d162585e22ed8c1e4114aa2f60e3567 upstream. Charge moving mode in cgroup1 allows memory to follow tasks as they migrate between cgroups. This is, and always has been, a questionable thing to do - for several reasons. First, it's expensive. Pages need to be identified, locked and isolated from various MM operations, and reassigned, one by one. Second, it's unreliable. Once pages are charged to a cgroup, there isn't always a clear owner task anymore. Cache isn't moved at all, for example. Mapped memory is moved - but if trylocking or isolating a page fails, it's arbitrarily left behind. Frequent moving between domains may leave a task's memory scattered all over the place. Third, it isn't really needed. Launcher tasks can kick off workload tasks directly in their target cgroup. Using dedicated per-workload groups allows fine-grained policy adjustments - no need to move tasks and their physical pages between control domains. The feature was never forward-ported to cgroup2, and it hasn't been missed. Despite it being a niche usecase, the maintenance overhead of supporting it is enormous. Because pages are moved while they are live and subject to various MM operations, the synchronization rules are complicated. There are lock_page_memcg() in MM and FS code, which non-cgroup people don't understand. In some cases we've been able to shift code and cgroup API calls around such that we can rely on native locking as much as possible. But that's fragile, and sometimes we need to hold MM locks for longer than we otherwise would (pte lock e.g.). Mark the feature deprecated. Hopefully we can remove it soon. And backport into -stable kernels so that people who develop against earlier kernels are warned about this deprecation as early as possible. [akpm@linux-foundation.org: fix memory.rst underlining] Link: https://lkml.kernel.org/r/Y5COd+qXwk/S+n8N@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeelb@google.com> Acked-by: Hugh Dickins <hughd@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-10docs: gdbmacros: print newest recordJohn Ogness1-1/+1
commit f2e4cca2f670c8e52fbb551a295f2afc9aa2bd72 upstream. @head_id points to the newest record, but the printing loop exits when it increments to this value (before printing). Exit the printing loop after the newest record has been printed. The python-based function in scripts/gdb/linux/dmesg.py already does this correctly. Fixes: e60768311af8 ("scripts/gdb: update for lockless printk ringbuffer") Cc: stable@vger.kernel.org Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221229134339.197627-1-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-10Documentation/hw-vuln: Document the interaction between IBRS and STIBPKP Singh1-5/+16
commit e02b50ca442e88122e1302d4dbc1b71a4808c13f upstream. Explain why STIBP is needed with legacy IBRS as currently implemented (KERNEL_IBRS) and why STIBP is not needed when enhanced IBRS is enabled. Fixes: 7c693f54c873 ("x86/speculation: Add spectre_v2=ibrs option to support Kernel IBRS") Signed-off-by: KP Singh <kpsingh@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230227060541.1939092-2-kpsingh@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-25docs: perf: Fix PMU instance name of hisi-pcie-pmuYicong Yang1-11/+11
[ Upstream commit eb79f12b4c41dd2403a0d16772ee72fcd6416015 ] The PMU instance will be called hisi_pcie<sicl>_core<core> rather than hisi_pcie<sicl>_<core>. Fix this in the documentation. Fixes: c8602008e247 ("docs: perf: Add description for HiSilicon PCIe PMU driver") Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Link: https://lore.kernel.org/r/20221117084136.53572-3-yangyicong@huawei.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-14Documentation/hw-vuln: Add documentation for Cross-Thread Return PredictionsTom Lendacky2-0/+93
commit 493a2c2d23ca91afba96ac32b6cbafb54382c2a3 upstream. Add the admin guide for the Cross-Thread Return Predictions vulnerability. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Message-Id: <60f9c0b4396956ce70499ae180cb548720b25c7e.1675956146.git.thomas.lendacky@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-24panic: Introduce warn_limitKees Cook1-0/+10
commit 9fc9e278a5c0b708eeffaf47d6eb0c82aa74ed78 upstream. Like oops_limit, add warn_limit for limiting the number of warnings when panic_on_warn is not set. Cc: Jonathan Corbet <corbet@lwn.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: "Jason A. Donenfeld" <Jason@zx2c4.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Petr Mladek <pmladek@suse.com> Cc: tangmeng <tangmeng@uniontech.com> Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com> Cc: Tiezhu Yang <yangtiezhu@loongson.cn> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: linux-doc@vger.kernel.org Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20221117234328.594699-5-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-24exit: Allow oops_limit to be disabledKees Cook1-2/+3
commit de92f65719cd672f4b48397540b9f9eff67eca40 upstream. In preparation for keeping oops_limit logic in sync with warn_limit, have oops_limit == 0 disable checking the Oops counter. Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: "Jason A. Donenfeld" <Jason@zx2c4.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Huang Ying <ying.huang@intel.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: linux-doc@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-24exit: Put an upper limit on how often we can oopsJann Horn1-0/+8
commit d4ccd54d28d3c8598e2354acc13e28c060961dbb upstream. Many Linux systems are configured to not panic on oops; but allowing an attacker to oops the system **really** often can make even bugs that look completely unexploitable exploitable (like NULL dereferences and such) if each crash elevates a refcount by one or a lock is taken in read mode, and this causes a counter to eventually overflow. The most interesting counters for this are 32 bits wide (like open-coded refcounts that don't use refcount_t). (The ldsem reader count on 32-bit platforms is just 16 bits, but probably nobody cares about 32-bit platforms that much nowadays.) So let's panic the system if the kernel is constantly oopsing. The speed of oopsing 2^32 times probably depends on several factors, like how long the stack trace is and which unwinder you're using; an empirically important one is whether your console is showing a graphical environment or a text console that oopses will be printed to. In a quick single-threaded benchmark, it looks like oopsing in a vfork() child with a very short stack trace only takes ~510 microseconds per run when a graphical console is active; but switching to a text console that oopses are printed to slows it down around 87x, to ~45 milliseconds per run. (Adding more threads makes this faster, but the actual oops printing happens under &die_lock on x86, so you can maybe speed this up by a factor of around 2 and then any further improvement gets eaten up by lock contention.) It looks like it would take around 8-12 days to overflow a 32-bit counter with repeated oopsing on a multi-core X86 system running a graphical environment; both me (in an X86 VM) and Seth (with a distro kernel on normal hardware in a standard configuration) got numbers in that ballpark. 12 days aren't *that* short on a desktop system, and you'd likely need much longer on a typical server system (assuming that people don't run graphical desktop environments on their servers), and this is a *very* noisy and violent approach to exploiting the kernel; and it also seems to take orders of magnitude longer on some machines, probably because stuff like EFI pstore will slow it down a ton if that's active. Signed-off-by: Jann Horn <jannh@google.com> Link: https://lore.kernel.org/r/20221107201317.324457-1-jannh@google.com Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20221117234328.594699-2-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-07iommu/amd: Fix ill-formed ivrs_ioapic, ivrs_hpet and ivrs_acpihid optionsKim Phillips1-5/+22
commit 1198d2316dc4265a97d0e8445a22c7a6d17580a4 upstream. Currently, these options cause the following libkmod error: libkmod: ERROR ../libkmod/libkmod-config.c:489 kcmdline_parse_result: \ Ignoring bad option on kernel command line while parsing module \ name: 'ivrs_xxxx[XX:XX' Fix by introducing a new parameter format for these options and throw a warning for the deprecated format. Users are still allowed to omit the PCI Segment if zero. Adding a Link: to the reason why we're modding the syntax parsing in the driver and not in libkmod. Fixes: ca3bf5d47cec ("iommu/amd: Introduces ivrs_acpihid kernel parameter") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/linux-modules/20200310082308.14318-2-lucas.demarchi@intel.com/ Reported-by: Kim Phillips <kim.phillips@amd.com> Co-developed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Kim Phillips <kim.phillips@amd.com> Link: https://lore.kernel.org/r/20220919155638.391481-2-kim.phillips@amd.com Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-31x86/split_lock: Add sysctl to control the misery modeGuilherme G. Piccoli1-0/+23
[ Upstream commit 727209376f4998bc84db1d5d8af15afea846a92b ] Commit b041b525dab9 ("x86/split_lock: Make life miserable for split lockers") changed the way the split lock detector works when in "warn" mode; basically, it not only shows the warn message, but also intentionally introduces a slowdown through sleeping plus serialization mechanism on such task. Based on discussions in [0], seems the warning alone wasn't enough motivation for userspace developers to fix their applications. This slowdown is enough to totally break some proprietary (aka. unfixable) userspace[1]. Happens that originally the proposal in [0] was to add a new mode which would warns + slowdown the "split locking" task, keeping the old warn mode untouched. In the end, that idea was discarded and the regular/default "warn" mode now slows down the applications. This is quite aggressive with regards proprietary/legacy programs that basically are unable to properly run in kernel with this change. While it is understandable that a malicious application could DoS by split locking, it seems unacceptable to regress old/proprietary userspace programs through a default configuration that previously worked. An example of such breakage was reported in [1]. Add a sysctl to allow controlling the "misery mode" behavior, as per Thomas suggestion on [2]. This way, users running legacy and/or proprietary software are allowed to still execute them with a decent performance while still observing the warning messages on kernel log. [0] https://lore.kernel.org/lkml/20220217012721.9694-1-tony.luck@intel.com/ [1] https://github.com/doitsujin/dxvk/issues/2938 [2] https://lore.kernel.org/lkml/87pmf4bter.ffs@tglx/ [ dhansen: minor changelog tweaks, including clarifying the actual problem ] Fixes: b041b525dab9 ("x86/split_lock: Make life miserable for split lockers") Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Tested-by: Andre Almeida <andrealmeid@igalia.com> Link: https://lore.kernel.org/all/20221024200254.635256-1-gpiccoli%40igalia.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-22Documentation: add amd-pstate kernel command line optionsPerry Yuan1-0/+11
Add a new amd pstate driver command line option to enable driver passive working mode via MSR and shared memory interface to request desired performance within abstract scale and the power management firmware (SMU) convert the perf requests into actual hardware pstates. Also the `disable` parameter can disable the pstate driver loading by adding `amd_pstate=disable` to kernel command line. Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Tested-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-11-22Documentation: amd-pstate: add driver working mode introductionPerry Yuan1-17/+13
Introduce the `amd_pstate` driver new working mode with `amd_pstate=passive` added to kernel command line. If there is no passive mode enabled by user, amd_pstate driver will be disabled by default for now. Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Tested-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-10-25media: vivid.rst: loop_video is set on the capture devnodeHans Verkuil1-1/+1
The example on how to use and test Capture Overlay specified the wrong video device node. Back in 2015 the loop_video control moved from the output device to the capture device, but this example code is still referring to the output video device. Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
2022-10-22Merge tag 'acpi-6.1-rc2' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI fixes from Rafael Wysocki: "These fix issues introduced during this merge window (ACPI/PCI, device enumeration and documentation) and some other ones found recently. Specifics: - Add missing device reference counting to acpi_get_pci_dev() after changing it recently (Rafael Wysocki) - Fix resource list walk in acpi_dma_get_range() (Robin Murphy) - Add IRQ override quirk for LENOVO IdeaPad and extend the IRQ override warning message (Jiri Slaby) - Fix integer overflow in ghes_estatus_pool_init() (Ashish Kalra) - Fix multiple error records handling in one of the ACPI extlog driver code paths (Tony Luck) - Prune DSDT override documentation from index after dropping it (Bagas Sanjaya)" * tag 'acpi-6.1-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI: scan: Fix DMA range assignment ACPI: PCI: Fix device reference counting in acpi_get_pci_dev() ACPI: resource: note more about IRQ override ACPI: resource: do IRQ override on LENOVO IdeaPad ACPI: extlog: Handle multiple records ACPI: APEI: Fix integer overflow in ghes_estatus_pool_init() Documentation: ACPI: Prune DSDT override documentation from index
2022-10-21Merge branches 'acpi-scan', 'acpi-resource', 'acpi-apei', 'acpi-extlog' and ↵Rafael J. Wysocki1-1/+0
'acpi-docs' Merge assorted ACPI fixes for 6.1-rc2: - Fix resource list walk in acpi_dma_get_range() (Robin Murphy). - Add IRQ override quirk for LENOVO IdeaPad and extend the IRQ override warning message (Jiri Slaby). - Fix integer overflow in ghes_estatus_pool_init() (Ashish Kalra). - Fix multiple error records handling in one of the ACPI extlog driver code paths (Tony Luck). - Prune DSDT override documentation from index after dropping it (Bagas Sanjaya). * acpi-scan: ACPI: scan: Fix DMA range assignment * acpi-resource: ACPI: resource: note more about IRQ override ACPI: resource: do IRQ override on LENOVO IdeaPad * acpi-apei: ACPI: APEI: Fix integer overflow in ghes_estatus_pool_init() * acpi-extlog: ACPI: extlog: Handle multiple records * acpi-docs: Documentation: ACPI: Prune DSDT override documentation from index
2022-10-19dm verity: Add documentation for try_verify_in_tasklet optionMilan Broz1-0/+4
Add documentation that was missing from commit 5721d4e5a9cd ("dm verity: Add optional "try_verify_in_tasklet" feature"). Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-10-14Merge tag 'sched-psi-2022-10-14' of ↵Linus Torvalds1-0/+23
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull PSI updates from Ingo Molnar: - Various performance optimizations, resulting in a 4%-9% speedup in the mmtests/config-scheduler-perfpipe micro-benchmark. - New interface to turn PSI on/off on a per cgroup level. * tag 'sched-psi-2022-10-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/psi: Per-cgroup PSI accounting disable/re-enable interface sched/psi: Cache parent psi_group to speed up group iteration sched/psi: Consolidate cgroup_psi() sched/psi: Add PSI_IRQ to track IRQ/SOFTIRQ pressure sched/psi: Remove NR_ONCPU task accounting sched/psi: Optimize task switch inside shared cgroups again sched/psi: Move private helpers to sched/stats.h sched/psi: Save percpu memory when !psi_cgroups_enabled sched/psi: Don't create cgroup PSI files when psi_disabled sched/psi: Fix periodic aggregation shut off
2022-10-13Documentation: ACPI: Prune DSDT override documentation from indexBagas Sanjaya1-1/+0
Commit d206cef03c4827 ("ACPI: docs: Drop useless DSDT override documentation") removes useless DSDT override documentation. However, the commit forgets to prune the documentation entry from table of contents of ACPI admin guide documentation, hence triggers Sphinx warning: Documentation/admin-guide/acpi/index.rst:8: WARNING: toctree contains reference to nonexisting document 'admin-guide/acpi/dsdt-override' Prune the entry to fix the warning. Fixes: d206cef03c4827 ("ACPI: docs: Drop useless DSDT override documentation") Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-10-13Merge tag 'for-linus-6.1-rc1-tag' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - Some minor typo fixes - A fix of the Xen pcifront driver for supporting the device model to run in a Linux stub domain - A cleanup of the pcifront driver - A series to enable grant-based virtio with Xen on x86 - A cleanup of Xen PV guests to distinguish between safe and faulting MSR accesses - Two fixes of the Xen gntdev driver - Two fixes of the new xen grant DMA driver * tag 'for-linus-6.1-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: Kconfig: Fix spelling mistake "Maxmium" -> "Maximum" xen/pv: support selecting safe/unsafe msr accesses xen/pv: refactor msr access functions to support safe and unsafe accesses xen/pv: fix vendor checks for pmu emulation xen/pv: add fault recovery control to pmu msr accesses xen/virtio: enable grant based virtio on x86 xen/virtio: use dom0 as default backend for CONFIG_XEN_VIRTIO_FORCE_GRANT xen/virtio: restructure xen grant dma setup xen/pcifront: move xenstore config scanning into sub-function xen/gntdev: Accommodate VMA splitting xen/gntdev: Prevent leaking grants xen/virtio: Fix potential deadlock when accessing xen_grant_dma_devices xen/virtio: Fix n_pages calculation in xen_grant_dma_map(unmap)_page() xen/xenbus: Fix spelling mistake "hardward" -> "hardware" xen-pcifront: Handle missed Connected state
2022-10-12Merge tag 'mm-nonmm-stable-2022-10-11' of ↵Linus Torvalds1-0/+5
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - hfs and hfsplus kmap API modernization (Fabio Francesco) - make crash-kexec work properly when invoked from an NMI-time panic (Valentin Schneider) - ntfs bugfixes (Hawkins Jiawei) - improve IPC msg scalability by replacing atomic_t's with percpu counters (Jiebin Sun) - nilfs2 cleanups (Minghao Chi) - lots of other single patches all over the tree! * tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (71 commits) include/linux/entry-common.h: remove has_signal comment of arch_do_signal_or_restart() prototype proc: test how it holds up with mapping'less process mailmap: update Frank Rowand email address ia64: mca: use strscpy() is more robust and safer init/Kconfig: fix unmet direct dependencies ia64: update config files nilfs2: replace WARN_ONs by nilfs_error for checkpoint acquisition failure fork: remove duplicate included header files init/main.c: remove unnecessary (void*) conversions proc: mark more files as permanent nilfs2: remove the unneeded result variable nilfs2: delete unnecessary checks before brelse() checkpatch: warn for non-standard fixes tag style usr/gen_init_cpio.c: remove unnecessary -1 values from int file ipc/msg: mitigate the lock contention with percpu counter percpu: add percpu_counter_add_local and percpu_counter_sub_local fs/ocfs2: fix repeated words in comments relay: use kvcalloc to alloc page array in relay_alloc_page_array proc: make config PROC_CHILDREN depend on PROC_FS fs: uninline inode_maybe_inc_iversion() ...
2022-10-11xen/pv: support selecting safe/unsafe msr accessesJuergen Gross1-0/+6
Instead of always doing the safe variants for reading and writing MSRs in Xen PV guests, make the behavior controllable via Kconfig option and a boot parameter. The default will be the current behavior, which is to always use the safe variant. Signed-off-by: Juergen Gross <jgross@suse.com>
2022-10-11Merge tag 'mm-stable-2022-10-08' of ↵Linus Torvalds13-35/+287
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in linux-next for a couple of months without, to my knowledge, any negative reports (or any positive ones, come to that). - Also the Maple Tree from Liam Howlett. An overlapping range-based tree for vmas. It it apparently slightly more efficient in its own right, but is mainly targeted at enabling work to reduce mmap_lock contention. Liam has identified a number of other tree users in the kernel which could be beneficially onverted to mapletrees. Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat at [1]. This has yet to be addressed due to Liam's unfortunately timed vacation. He is now back and we'll get this fixed up. - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses clang-generated instrumentation to detect used-unintialized bugs down to the single bit level. KMSAN keeps finding bugs. New ones, as well as the legacy ones. - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of memory into THPs. - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to support file/shmem-backed pages. - userfaultfd updates from Axel Rasmussen - zsmalloc cleanups from Alexey Romanov - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and memory-failure - Huang Ying adds enhancements to NUMA balancing memory tiering mode's page promotion, with a new way of detecting hot pages. - memcg updates from Shakeel Butt: charging optimizations and reduced memory consumption. - memcg cleanups from Kairui Song. - memcg fixes and cleanups from Johannes Weiner. - Vishal Moola provides more folio conversions - Zhang Yi removed ll_rw_block() :( - migration enhancements from Peter Xu - migration error-path bugfixes from Huang Ying - Aneesh Kumar added ability for a device driver to alter the memory tiering promotion paths. For optimizations by PMEM drivers, DRM drivers, etc. - vma merging improvements from Jakub Matěn. - NUMA hinting cleanups from David Hildenbrand. - xu xin added aditional userspace visibility into KSM merging activity. - THP & KSM code consolidation from Qi Zheng. - more folio work from Matthew Wilcox. - KASAN updates from Andrey Konovalov. - DAMON cleanups from Kaixu Xia. - DAMON work from SeongJae Park: fixes, cleanups. - hugetlb sysfs cleanups from Muchun Song. - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core. Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1] * tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits) hugetlb: allocate vma lock for all sharable vmas hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer hugetlb: fix vma lock handling during split vma and range unmapping mglru: mm/vmscan.c: fix imprecise comments mm/mglru: don't sync disk for each aging cycle mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol mm: memcontrol: use do_memsw_account() in a few more places mm: memcontrol: deprecate swapaccounting=0 mode mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled mm/secretmem: remove reduntant return value mm/hugetlb: add available_huge_pages() func mm: remove unused inline functions from include/linux/mm_inline.h selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd selftests/vm: add thp collapse shmem testing selftests/vm: add thp collapse file and tmpfs testing selftests/vm: modularize thp collapse memory operations selftests/vm: dedup THP helpers mm/khugepaged: add tracepoint to hpage_collapse_scan_file() mm/madvise: add file and shmem support to MADV_COLLAPSE ...
2022-10-10Merge tag 'iommu-updates-v6.1' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull iommu updates from Joerg Roedel: - remove the bus_set_iommu() interface which became unnecesary because of IOMMU per-device probing - make the dma-iommu.h header private - Intel VT-d changes from Lu Baolu: - Decouple PASID and PRI from SVA - Add ESRTPS & ESIRTPS capability check - Cleanups - Apple DART support for the M1 Pro/MAX SOCs - support for AMD IOMMUv2 page-tables for the DMA-API layer. The v2 page-tables are compatible with the x86 CPU page-tables. Using them for DMA-API prepares support for hardware-assisted IOMMU virtualization - support for MT6795 Helio X10 M4Us in the Mediatek IOMMU driver - some smaller fixes and cleanups * tag 'iommu-updates-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (59 commits) iommu/vt-d: Avoid unnecessary global DMA cache invalidation iommu/vt-d: Avoid unnecessary global IRTE cache invalidation iommu/vt-d: Rename cap_5lp_support to cap_fl5lp_support iommu/vt-d: Remove pasid_set_eafe() iommu/vt-d: Decouple PASID & PRI enabling from SVA iommu/vt-d: Remove unnecessary SVA data accesses in page fault path dt-bindings: iommu: arm,smmu-v3: Relax order of interrupt names iommu: dart: Support t6000 variant iommu/io-pgtable-dart: Add DART PTE support for t6000 iommu/io-pgtable: Add DART subpage protection support iommu/io-pgtable: Move Apple DART support to its own file iommu/mediatek: Add support for MT6795 Helio X10 M4Us iommu/mediatek: Introduce new flag TF_PORT_TO_ADDR_MT8173 dt-bindings: mediatek: Add bindings for MT6795 M4U iommu/iova: Fix module config properly iommu/amd: Fix sparse warning iommu/amd: Remove outdated comment iommu/amd: Free domain ID after domain_flush_pages iommu/amd: Free domain id in error path iommu/virtio: Fix compile error with viommu_capable() ...
2022-10-10Merge tag 'cgroup-for-6.1' of ↵Linus Torvalds1-69/+87
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: - cpuset now support isolated cpus.partition type, which will enable dynamic CPU isolation - pids.peak added to remember the max number of pids used - holes in cgroup namespace plugged - internal cleanups * tag 'cgroup-for-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (25 commits) cgroup: use strscpy() is more robust and safer iocost_monitor: reorder BlkgIterator cgroup: simplify code in cgroup_apply_control cgroup: Make cgroup_get_from_id() prettier cgroup/cpuset: remove unreachable code cgroup: Remove CFTYPE_PRESSURE cgroup: Improve cftype add/rm error handling kselftest/cgroup: Add cpuset v2 partition root state test cgroup/cpuset: Update description of cpuset.cpus.partition in cgroup-v2.rst cgroup/cpuset: Make partition invalid if cpumask change violates exclusivity rule cgroup/cpuset: Relocate a code block in validate_change() cgroup/cpuset: Show invalid partition reason string cgroup/cpuset: Add a new isolated cpus.partition type cgroup/cpuset: Relax constraints to partition & cpus changes cgroup/cpuset: Allow no-task partition to have empty cpuset.cpus.effective cgroup/cpuset: Miscellaneous cleanups & add helper functions cgroup/cpuset: Enable update_tasks_cpumask() on top_cpuset cgroup: add pids.peak interface for pids controller cgroup: Remove data-race around cgrp_dfl_visible cgroup: Fix build failure when CONFIG_SHRINKER_DEBUG ...
2022-10-10Merge tag 'powerpc-6.1-1' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Remove our now never-true definitions for pgd_huge() and p4d_leaf(). - Add pte_needs_flush() and huge_pmd_needs_flush() for 64-bit. - Add support for syscall wrappers. - Add support for KFENCE on 64-bit. - Update 64-bit HV KVM to use the new guest state entry/exit accounting API. - Support execute-only memory when using the Radix MMU (P9 or later). - Implement CONFIG_PARAVIRT_TIME_ACCOUNTING for pseries guests. - Updates to our linker script to move more data into read-only sections. - Allow the VDSO to be randomised on 32-bit. - Many other small features and fixes. Thanks to Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira Rajeev, Christophe Leroy, David Hildenbrand, Disha Goel, Fabiano Rosas, Gaosheng Cui, Gustavo A. R. Silva, Haren Myneni, Hari Bathini, Jilin Yuan, Joel Stanley, Kajol Jain, Kees Cook, Krzysztof Kozlowski, Laurent Dufour, Liang He, Li Huafei, Lukas Bulwahn, Madhavan Srinivasan, Nathan Chancellor, Nathan Lynch, Nicholas Miehlbradt, Nicholas Piggin, Pali Rohár, Rohan McLure, Russell Currey, Sachin Sant, Segher Boessenkool, Shrikanth Hegde, Tyrel Datwyler, Wolfram Sang, ye xingchen, and Zheng Yongjun. * tag 'powerpc-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits) KVM: PPC: Book3S HV: Fix stack frame regs marker powerpc: Don't add __powerpc_ prefix to syscall entry points powerpc/64s/interrupt: Fix stack frame regs marker powerpc/64: Fix msr_check_and_set/clear MSR[EE] race powerpc/64s/interrupt: Change must-hard-mask interrupt check from BUG to WARN powerpc/pseries: Add firmware details to the hardware description powerpc/powernv: Add opal details to the hardware description powerpc: Add device-tree model to the hardware description powerpc/64: Add logical PVR to the hardware description powerpc: Add PVR & CPU name to hardware description powerpc: Add hardware description string powerpc/configs: Enable PPC_UV in powernv_defconfig powerpc/configs: Update config files for removed/renamed symbols powerpc/mm: Fix UBSAN warning reported on hugetlb powerpc/mm: Always update max/min_low_pfn in mem_topology_setup() powerpc/mm/book3s/hash: Rename flush_tlb_pmd_range powerpc: Drops STABS_DEBUG from linker scripts powerpc/64s: Remove lost/old comment powerpc/64s: Remove old STAB comment powerpc: remove orphan systbl_chk.sh ...
2022-10-09Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-0/+5
Pull kvm updates from Paolo Bonzini: "The first batch of KVM patches, mostly covering x86. ARM: - Account stage2 page table allocations in memory stats x86: - Account EPT/NPT arm64 page table allocations in memory stats - Tracepoint cleanups/fixes for nested VM-Enter and emulated MSR accesses - Drop eVMCS controls filtering for KVM on Hyper-V, all known versions of Hyper-V now support eVMCS fields associated with features that are enumerated to the guest - Use KVM's sanitized VMCS config as the basis for the values of nested VMX capabilities MSRs - A myriad event/exception fixes and cleanups. Most notably, pending exceptions morph into VM-Exits earlier, as soon as the exception is queued, instead of waiting until the next vmentry. This fixed a longstanding issue where the exceptions would incorrecly become double-faults instead of triggering a vmexit; the common case of page-fault vmexits had a special workaround, but now it's fixed for good - A handful of fixes for memory leaks in error paths - Cleanups for VMREAD trampoline and VMX's VM-Exit assembly flow - Never write to memory from non-sleepable kvm_vcpu_check_block() - Selftests refinements and cleanups - Misc typo cleanups Generic: - remove KVM_REQ_UNHALT" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (94 commits) KVM: remove KVM_REQ_UNHALT KVM: mips, x86: do not rely on KVM_REQ_UNHALT KVM: x86: never write to memory from kvm_vcpu_check_block() KVM: x86: Don't snapshot pending INIT/SIPI prior to checking nested events KVM: nVMX: Make event request on VMXOFF iff INIT/SIPI is pending KVM: nVMX: Make an event request if INIT or SIPI is pending on VM-Enter KVM: SVM: Make an event request if INIT or SIPI is pending when GIF is set KVM: x86: lapic does not have to process INIT if it is blocked KVM: x86: Rename kvm_apic_has_events() to make it INIT/SIPI specific KVM: x86: Rename and expose helper to detect if INIT/SIPI are allowed KVM: nVMX: Make an event request when pending an MTF nested VM-Exit KVM: x86: make vendor code check for all nested events mailmap: Update Oliver's email address KVM: x86: Allow force_emulation_prefix to be written without a reload KVM: selftests: Add an x86-only test to verify nested exception queueing KVM: selftests: Use uapi header to get VMX and SVM exit reasons/codes KVM: x86: Rename inject_pending_events() to kvm_check_and_inject_events() KVM: VMX: Update MTF and ICEBP comments to document KVM's subtle behavior KVM: x86: Treat pending TRIPLE_FAULT requests as pending exceptions KVM: x86: Morph pending exceptions to pending VM-Exits at queue time ...
2022-10-08Merge tag 'driver-core-6.1-rc1' of ↵Linus Torvalds1-118/+128
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the big set of driver core and debug printk changes for 6.1-rc1. Included in here is: - dynamic debug updates for the core and the drm subsystem. The drm changes have all been acked by the relevant maintainers - kernfs fixes for syzbot reported problems - kernfs refactors and updates for cgroup requirements - magic number cleanups and removals from the kernel tree (they were not being used and they really did not actually do anything) - other tiny cleanups All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (74 commits) docs: filesystems: sysfs: Make text and code for ->show() consistent Documentation: NBD_REQUEST_MAGIC isn't a magic number a.out: restore CMAGIC device property: Add const qualifier to device_get_match_data() parameter drm_print: add _ddebug descriptor to drm_*dbg prototypes drm_print: prefer bare printk KERN_DEBUG on generic fn drm_print: optimize drm_debug_enabled for jump-label drm-print: add drm_dbg_driver to improve namespace symmetry drm-print.h: include dyndbg header drm_print: wrap drm_*_dbg in dyndbg descriptor factory macro drm_print: interpose drm_*dbg with forwarding macros drm: POC drm on dyndbg - use in core, 2 helpers, 3 drivers. drm_print: condense enum drm_debug_category debugfs: use DEFINE_SHOW_ATTRIBUTE to define debugfs_regset32_fops driver core: use IS_ERR_OR_NULL() helper in device_create_groups_vargs() Documentation: ENI155_MAGIC isn't a magic number Documentation: NBD_REPLY_MAGIC isn't a magic number nbd: remove define-only NBD_MAGIC, previously magic number Documentation: FW_HEADER_MAGIC isn't a magic number Documentation: EEPROM_MAGIC_VALUE isn't a magic number ...