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2024-11-07um: remove duplicate UM_NSEC_PER_SEC definitionBenjamin Berg
Just remove the first entry as there is a second later on. Signed-off-by: Benjamin Berg <benjamin.berg@intel.com> Link: https://patch.msgid.link/20241103150506.1367695-4-benjamin@sipsolutions.net Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-11-07um: remove file sync for stub dataBenjamin Berg
There is no need to sync the stub code to "disk" for the other process to see the correct memory. Drop the fsync there and remove the helper function. Signed-off-by: Benjamin Berg <benjamin.berg@intel.com> Link: https://patch.msgid.link/20241103150506.1367695-3-benjamin@sipsolutions.net Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-11-07um: always include kconfig.h and compiler-version.hBenjamin Berg
Since commit a95b37e20db9 ("kbuild: get <linux/compiler_types.h> out of <linux/kconfig.h>") we can safely include these files in userspace code. Doing so simplifies matters as options do not need to be exported via asm-offsets.h anymore. Signed-off-by: Benjamin Berg <benjamin.berg@intel.com> Link: https://patch.msgid.link/20241103150506.1367695-2-benjamin@sipsolutions.net Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-11-07um: set DONTDUMP and DONTFORK flags on KASAN shadow memoryBenjamin Berg
There is no point in either dumping the KASAN shadow memory or doing copy-on-write after a fork on these memory regions. This considerably speeds up coredump generation. Signed-off-by: Benjamin Berg <benjamin.berg@intel.com> Link: https://patch.msgid.link/20241103150506.1367695-1-benjamin@sipsolutions.net Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-11-07um: fix sparse warnings in signal codeBenjamin Berg
sparse reports that various places were missing the __user tag in casts. In addition, one location was using 0 instead of NULL. Signed-off-by: Benjamin Berg <benjamin.berg@intel.com> Link: https://patch.msgid.link/20241031142017.430420-2-benjamin@sipsolutions.net Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-11-07um: fix sparse warnings from regset refactorBenjamin Berg
Some variables were not tagged with __user and another was not marked as static even though it should be. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202410280655.gOlEFwdG-lkp@intel.com/ Closes: https://lore.kernel.org/oe-kbuild-all/202410281821.WSPsAwq7-lkp@intel.com/ Fixes: 3f17fed21491 ("um: switch to regset API and depend on XSTATE") Signed-off-by: Benjamin Berg <benjamin.berg@intel.com> Link: https://patch.msgid.link/20241031142017.430420-1-benjamin@sipsolutions.net Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-11-07um: Remove double zero checkShaojie Dong
free_pages() performs a parameter null check inside therefore remove double zero check here. Signed-off-by: Shaojie Dong <quic_shaojied@quicinc.com> Link: https://patch.msgid.link/20241025-upstream_branch-v5-1-b8998beb2c64@quicinc.com Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-11-07arm64: dts: sun50i-a64-pinephone: Add mount-matrix for PinePhone magnetometersShoji Keita
For lis3mdl, values are based on datasheet and PCB drawing and tested on a real device. For af8133j, values are from testing on a real device. Signed-off-by: Shoji Keita <awaittrot@shjk.jp> Signed-off-by: Andrey Skvortsov <andrej.skvortzov@gmail.com> Link: https://patch.msgid.link/20240908214718.36316-3-andrej.skvortzov@gmail.com Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2024-11-07arm64: dts: sun50i-a64-pinephone: Add AF8133J to PinePhoneIcenowy Zheng
New batches of PinePhones switched the magnetometer to AF8133J from LIS3MDL because lack of ST components. Both chips use the same PB1 pin, but in different modes. LIS3MDL uses it as an gpio input to handle interrupt. AF8133J uses it as an gpio output as a reset signal. It wasn't possible at runtime to enable both device tree nodes and detect supported sensor at probe time, because both drivers try to acquire the same gpio in different modes. Device tree fixup will be done in firmware without introducing new board revision and new dts. Signed-off-by: Icenowy Zheng <icenowy@aosc.io> Signed-off-by: Andrey Skvortsov <andrej.skvortzov@gmail.com> Link: https://patchwork.ozlabs.org/project/uboot/patch/20240211092824.395155-1-andrej.skvortzov@gmail.com/ Link: https://patch.msgid.link/20240908214718.36316-2-andrej.skvortzov@gmail.com Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2024-11-07arm64: fix .data.rel.ro size assertion when CONFIG_LTO_CLANGMasahiro Yamada
Commit be2881824ae9 ("arm64/build: Assert for unwanted sections") introduced an assertion to ensure that the .data.rel.ro section does not exist. However, this check does not work when CONFIG_LTO_CLANG is enabled, because .data.rel.ro matches the .data.[0-9a-zA-Z_]* pattern in the DATA_MAIN macro. Move the ASSERT() above the RW_DATA() line. Fixes: be2881824ae9 ("arm64/build: Assert for unwanted sections") Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20241106161843.189927-1-masahiroy@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-11-07arm64: Kconfig: Make SME depend on BROKEN for nowMark Rutland
Although support for SME was merged in v5.19, we've since uncovered a number of issues with the implementation, including issues which might corrupt the FPSIMD/SVE/SME state of arbitrary tasks. While there are patches to address some of these issues, ongoing review has highlighted additional functional problems, and more time is necessary to analyse and fix these. For now, mark SME as BROKEN in the hope that we can fix things properly in the near future. As SME is an OPTIONAL part of ARMv9.2+, and there is very little extant hardware, this should not adversely affect the vast majority of users. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Cc: stable@vger.kernel.org # 5.19 Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20241106164220.2789279-1-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-11-07arm64: smccc: Remove broken support for SMCCCv1.3 SVE discard hintMark Rutland
SMCCCv1.3 added a hint bit which callers can set in an SMCCC function ID (AKA "FID") to indicate that it is acceptable for the SMCCC implementation to discard SVE and/or SME state over a specific SMCCC call. The kernel support for using this hint is broken and SMCCC calls may clobber the SVE and/or SME state of arbitrary tasks, though FPSIMD state is unaffected. The kernel support is intended to use the hint when there is no SVE or SME state to save, and to do this it checks whether TIF_FOREIGN_FPSTATE is set or TIF_SVE is clear in assembly code: | ldr <flags>, [<current_task>, #TSK_TI_FLAGS] | tbnz <flags>, #TIF_FOREIGN_FPSTATE, 1f // Any live FP state? | tbnz <flags>, #TIF_SVE, 2f // Does that state include SVE? | | 1: orr <fid>, <fid>, ARM_SMCCC_1_3_SVE_HINT | 2: | << SMCCC call using FID >> This is not safe as-is: (1) SMCCC calls can be made in a preemptible context and preemption can result in TIF_FOREIGN_FPSTATE being set or cleared at arbitrary points in time. Thus checking for TIF_FOREIGN_FPSTATE provides no guarantee. (2) TIF_FOREIGN_FPSTATE only indicates that the live FP/SVE/SME state in the CPU does not belong to the current task, and does not indicate that clobbering this state is acceptable. When the live CPU state is clobbered it is necessary to update fpsimd_last_state.st to ensure that a subsequent context switch will reload FP/SVE/SME state from memory rather than consuming the clobbered state. This and the SMCCC call itself must happen in a critical section with preemption disabled to avoid races. (3) Live SVE/SME state can exist with TIF_SVE clear (e.g. with only TIF_SME set), and checking TIF_SVE alone is insufficient. Remove the broken support for the SMCCCv1.3 SVE saving hint. This is effectively a revert of commits: * cfa7ff959a78 ("arm64: smccc: Support SMCCC v1.3 SVE register saving hint") * a7c3acca5380 ("arm64: smccc: Save lr before calling __arm_smccc_sve_check()") ... leaving behind the ARM_SMCCC_VERSION_1_3 and ARM_SMCCC_1_3_SVE_HINT definitions, since these are simply definitions from the SMCCC specification, and the latter is used in KVM via ARM_SMCCC_CALL_HINTS. If we want to bring this back in future, we'll probably want to handle this logic in C where we can use all the usual FPSIMD/SVE/SME helper functions, and that'll likely require some rework of the SMCCC code and/or its callers. Fixes: cfa7ff959a78 ("arm64: smccc: Support SMCCC v1.3 SVE register saving hint") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Cc: stable@vger.kernel.org Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241106160448.2712997-1-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-11-07x86/sev: Cleanup vc_handle_msr()Borislav Petkov (AMD)
Carve out the MSR_SVSM_CAA into a helper with the suggestion that upcoming future users should do the same. Rename that silly exit_info_1 into what it actually means in this function - whether the MSR access is a read or a write. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Link: https://lore.kernel.org/r/20241106172647.GAZyum1zngPDwyD2IJ@fat_crate.local
2024-11-07s390/pci: Add header guards and includes to internal headersNiklas Schnelle
While pci_iov.h has include guards it doesn't include the necessary header for struct zpci_dev, pci_bus.h on the other hand lacks even basic include guards. This isn't only fragile and breaks convention but also confuses tooling such as clang-analyzer. Add both include guards and the necessary includes. Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Reviewed-by: Gerd Bayer <gbayer@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-07s390/sparsemem: Provide phys_to_target_node() with CONFIG_NUMAHeiko Carstens
Add a trival phys_to_target_node() implementation which always returns 0 if CONFIG_NUMA is enabled, since the s390 NUMA implementation only supports node 0. This is similar to memory_add_physaddr_to_nid() in order to avoid runtime warnings. Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-07s390/configs: Enable CONFIG_VIRTIO_MEMHeiko Carstens
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-07s390/sparsemem: Provide memory_add_physaddr_to_nid() with CONFIG_NUMADavid Hildenbrand
virtio-mem uses memory_add_physaddr_to_nid() to determine the NID to use for memory it adds. We currently fallback to the dummy implementation in mm/numa.c with CONFIG_NUMA, which will end up triggering an undesired pr_info_once(): Unknown online node for memory at 0x100000000, assuming node 0 On s390, we map all cpus and memory to node 0, so let's add a simple memory_add_physaddr_to_nid() implementation that does exactly that, but without complaining. Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Tested-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com> Link: https://lore.kernel.org/r/20241025141453.1210600-8-david@redhat.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-07s390/sparsemem: Reduce section size to 128 MiBDavid Hildenbrand
Ever since commit 421c175c4d609 ("[S390] Add support for memory hot-add.") we've been using a section size of 256 MiB on s390 and 32 MiB on s390. Before that, we were using a section size of 32 MiB on both architectures. Now that we have a new mechanism to expose additional memory to a VM -- virtio-mem -- reduce the section size to 128 MiB to allow for more flexibility and reduce the metadata overhead when dealing with hot(un)plug granularity smaller than 256 MiB. 128 MiB has been used by x86-64 since the very beginning. arm64 with 4k base pages switched to 128 MiB as well: it's just big enough on these architectures to allows for using a huge page (2 MiB) in the vmemmap in sane setups with sizeof(struct page) == 64 bytes and a huge page mapping in the direct mapping, while still allowing for small hot(un)plug granularity. For s390, we could even switch to a 64 MiB section size, as our huge page size is 1 MiB: but the smaller the section size, the more sections we'll have to manage especially on bigger machines. Making it consistent with x86-64 and arm64 feels like the right thing for now. Note that the smallest memory hot(un)plug granularity is also limited by the memory block size, determined by extracting the memory increment size from SCLP. Under QEMU/KVM, implementing virtio-mem, we expose 0; therefore, we'll end up with a memory block size of 128 MiB with a 128 MiB section size. Tested-by: Mario Casquero <mcasquer@redhat.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: David Hildenbrand <david@redhat.com> Tested-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com> Link: https://lore.kernel.org/r/20241025141453.1210600-7-david@redhat.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-07s390/physmem_info: Query diag500(STORAGE LIMIT) to support QEMU/KVM memory ↵David Hildenbrand
devices To support memory devices under QEMU/KVM, such as virtio-mem, we have to prepare our kernel virtual address space accordingly and have to know the highest possible physical memory address we might see later: the storage limit. The good old SCLP interface is not suitable for this use case. In particular, memory owned by memory devices has no relationship to storage increments, it is always detected using the device driver, and unaware OSes (no driver) must never try making use of that memory. Consequently this memory is located outside of the "maximum storage increment"-indicated memory range. Let's use our new diag500 STORAGE_LIMIT subcode to query this storage limit that can exceed the "maximum storage increment", and use the existing interfaces (i.e., SCLP) to obtain information about the initial memory that is not owned+managed by memory devices. If a hypervisor does not support such memory devices, the address exposed through diag500 STORAGE_LIMIT will correspond to the maximum storage increment exposed through SCLP. To teach kdump on s390 to include memory owned by memory devices, there will be ways to query the relevant memory ranges from the device via a driver running in special kdump mode (like virtio-mem already implements to filter /proc/vmcore access so we don't end up reading from unplugged device blocks). Update setup_ident_map_size(), to clarify that there can be more than just online and standby memory. Tested-by: Mario Casquero <mcasquer@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Tested-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com> Link: https://lore.kernel.org/r/20241025141453.1210600-4-david@redhat.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-07s390/kvm: Mask extra bits from program interrupt codeClaudio Imbrenda
The program interrupt code has some extra bits that are sometimes set by hardware for various reasons; those bits should be ignored when the program interrupt number is needed for interrupt handling. Fixes: 05066cafa925 ("s390/mm/fault: Handle guest-related program interrupts in KVM") Reported-by: Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Tested-by: Christian Borntraeger <borntraeger@linux.ibm.com> Link: https://lore.kernel.org/r/20241031120316.25462-1-imbrenda@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-06x86/percpu: fix clang warning when dealing with unsigned typesAndy Shevchenko
Patch series "percpu: Add a test case and fix for clang", v2. Add a test case to percpu to check a corner case with the specific 64-bit unsigned value. This test case shows why the first patch is done in the way it's done. The before and after has been tested with binary comparison of the percpu_test module and runnig it on the real Intel system. This patch (of 2): When percpu_add_op() is used with an unsigned argument, it prevents kernel builds with clang, `make W=1` and CONFIG_WERROR=y: net/ipv4/tcp_output.c:187:3: error: result of comparison of constant -1 with expression of type 'u8' (aka 'unsigned char') is always false [-Werror,-Wtautological-constant-out-of-range-compare] 187 | NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPACKCOMPRESSED, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 188 | tp->compressed_ack); | ~~~~~~~~~~~~~~~~~~~ ... arch/x86/include/asm/percpu.h:238:31: note: expanded from macro 'percpu_add_op' 238 | ((val) == 1 || (val) == -1)) ? \ | ~~~~~ ^ ~~ Fix this by casting -1 to the type of the parameter and then compare. Link: https://lkml.kernel.org/r/20241016182635.1156168-1-andriy.shevchenko@linux.intel.com Link: https://lkml.kernel.org/r/20241016182635.1156168-2-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Christoph Lameter <cl@linux.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: remove unused hugepage for vma_alloc_folio()Kefeng Wang
The hugepage parameter was deprecated since commit ddc1a5cbc05d ("mempolicy: alloc_pages_mpol() for NUMA policy without vma"), for PMD-sized THP, it still tries only preferred node if possible in vma_alloc_folio() by checking the order of the folio allocation. Link: https://lkml.kernel.org/r/20241010061556.1846751-1-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Barry Song <baohua@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06kaslr: rename physmem_end and PHYSMEM_END to direct_map_physmem_endJohn Hubbard
For clarity. It's increasingly hard to reason about the code, when KASLR is moving around the boundaries. In this case where KASLR is randomizing the location of the kernel image within physical memory, the maximum number of address bits for physical memory has not changed. What has changed is the ending address of memory that is allowed to be directly mapped by the kernel. Let's name the variable, and the associated macro accordingly. Also, enhance the comment above the direct_map_physmem_end definition, to further clarify how this all works. Link: https://lkml.kernel.org/r/20241009025024.89813-1-jhubbard@nvidia.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Will Deacon <will@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alistair Popple <apopple@nvidia.com> Cc: Jordan Niethe <jniethe@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: consolidate common checks in hugetlb_get_unmapped_areaOscar Salvador
prepare_hugepage_range() performs almost the same checks for all architectures that define it, with the exception of mips and loongarch that also check for overflows. The rest checks for the addr and len to be properly aligned, so we can move that to hugetlb_get_unmapped_area() and get rid of a fair amount of duplicated code. [akpm@linux-foundation.org: remove now-unused local] Link: https://lore.kernel.org/oe-kbuild-all/202410081210.uNLbf3Jk-lkp@intel.com/ Link: https://lkml.kernel.org/r/20241007075037.267650-10-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06arch/s390: clean up hugetlb definitionsOscar Salvador
s390 redefines functions that are already defined (and the same) in include/asm-generic/hugetlb.h. Do as the other architectures: 1) include include/asm-generic/hugetlb.h 2) drop the already defined functions in the generic hugetlb.h and 3) use the __HAVE_ARCH_HUGE_* macros to define our own. This gets rid of quite some code. Link: https://lkml.kernel.org/r/20241007075037.267650-9-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: drop hugetlb_get_unmapped_area{_*} functionsOscar Salvador
Hugetlb mappings are now handled through normal channels just like any other mapping, so we no longer need hugetlb_get_unmapped_area* specific functions. Link: https://lkml.kernel.org/r/20241007075037.267650-8-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06arch/powerpc: teach book3s64 arch_get_unmapped_area{_topdown} to handle ↵Oscar Salvador
hugetlb mappings We want to stop special casing hugetlb mappings and make them go through generic channels, so teach arch_get_unmapped_area{_topdown} to handle those. Reshuffle file_to_psize() definition so arch_get_unmapped_area{_topdown} can make use of it. Link: https://lkml.kernel.org/r/20241007075037.267650-6-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06arch/sparc: teach arch_get_unmapped_area{_topdown} to handle hugetlb mappingsOscar Salvador
We want to stop special casing hugetlb mappings and make them go through generic channels, so teach arch_get_unmapped_area{_topdown} to handle those. sparc specific hugetlb function does not set info.align_offset, and does not care about adjusting the align_mask for MAP_SHARED cases, so the same here for compatibility. Link: https://lkml.kernel.org/r/20241007075037.267650-5-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06arch/x86: teach arch_get_unmapped_area_vmflags to handle hugetlb mappingsOscar Salvador
We want to stop special casing hugetlb mappings and make them go through generic channels, so teach arch_get_unmapped_area_{topdown_}vmflags to handle those. x86 specific hugetlb function does not set either info.start_gap or info.align_offset so the same here for compatibility. Link: https://lkml.kernel.org/r/20241007075037.267650-4-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06arch/s390: teach arch_get_unmapped_area{_topdown} to handle hugetlb mappingsOscar Salvador
We want to stop special casing hugetlb mappings and make them go through generic channels, so teach arch_get_unmapped_area{_topdown} to handle those. s390 specific hugetlb function does not set info.align_offset, so do the same here for compatibility. Link: https://lkml.kernel.org/r/20241007075037.267650-3-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: move set_pxd_safe() helpers from generic to platformAnshuman Khandual
set_pxd_safe() helpers that serve a specific purpose for both x86 and riscv platforms, do not need to be in the common memory code. Otherwise they just unnecessarily make the common API more complicated. This moves the helpers from common code to platform instead. Link: https://lkml.kernel.org/r/20241003044842.246016-1-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Suggested-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Hildenbrand <david@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07KVM: x86/xen: Initialize hrtimer in kvm_xen_init_vcpu()Nam Cao
The hrtimer is initialized in the KVM_XEN_VCPU_SET_ATTR ioctl. That caused problem in the past, because the hrtimer can be initialized multiple times, which was fixed by commit af735db31285 ("KVM: x86/xen: Initialize Xen timer only once"). This commit avoids initializing the timer multiple times by checking the field 'function' of struct hrtimer to determine if it has already been initialized. This is not required and in the way to make the function field private. Move the hrtimer initialization into kvm_xen_init_vcpu() so that it will only be initialized once. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/all/9c33c7224d97d08f4fa30d3cc8687981c1d3e953.1730386209.git.namcao@linutronix.de
2024-11-06riscv: dts: thead: Add TH1520 ethernet nodesEmil Renner Berthing
Add gmac, mdio, and phy nodes to enable the gigabit Ethernet ports on the BeagleV Ahead and Sipeed Lichee Pi 4a boards. Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> [drew: change apb registers from syscon to second reg of gmac node, add phy reset delay properties for beaglev ahead] Signed-off-by: Drew Fustini <dfustini@tenstorrent.com>
2024-11-07powerpc/ps3: Mark ps3_setup_uhc_device() __initGeert Uytterhoeven
ps3_setup_uhc_device() is only called from ps3_setup_ehci_device() and ps3_setup_ohci_device(), which are both marked __init. Hence replace the former's __ref marker by __init. Note that before commit bd721ea73e1f9655 ("treewide: replace obsolete _refok by __ref"), the function was marked __init_refok, which probably should have been __init in the first place. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/31fe9435056fcfbf82c3a01693be278d5ce4ad0f.1730899557.git.geert+renesas@glider.be
2024-11-07riscv: defconfig: Enable T-HEAD C900 ACLINT SSWI driversInochi Amaoto
Add support for T-HEAD C900 ACLINT SSWI irqchip. Signed-off-by: Inochi Amaoto <inochiama@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20241031060859.722258-4-inochiama@gmail.com
2024-11-06PCI: Detect and trust built-in Thunderbolt chipsEsther Shimanovich
Some computers with CPUs that lack Thunderbolt features use discrete Thunderbolt chips to add Thunderbolt functionality. These Thunderbolt chips are located within the chassis; between the Root Port labeled ExternalFacingPort and the USB-C port. These Thunderbolt PCIe devices should be labeled as fixed and trusted, as they are built into the computer. Otherwise, security policies that rely on those flags may have unintended results, such as preventing USB-C ports from enumerating. Detect the above scenario through the process of elimination. 1) Integrated Thunderbolt host controllers already have Thunderbolt implemented, so anything outside their external facing Root Port is removable and untrusted. Detect them using the following properties: - Most integrated host controllers have the "usb4-host-interface" ACPI property, as described here: https://learn.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#mapping-native-protocols-pcie-displayport-tunneled-through-usb4-to-usb4-host-routers - Integrated Thunderbolt PCIe Root Ports before Alder Lake do not have the "usb4-host-interface" ACPI property. Identify those by their PCI IDs instead. 2) If a Root Port does not have integrated Thunderbolt capabilities, but has the "ExternalFacingPort" ACPI property, that means the manufacturer has opted to use a discrete Thunderbolt host controller that is built into the computer. This host controller can be identified by virtue of being located directly below an external-facing Root Port that lacks integrated Thunderbolt. Label it as trusted and fixed. Everything downstream from it is untrusted and removable. The "ExternalFacingPort" ACPI property is described here: https://learn.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-externally-exposed-pcie-root-ports Link: https://lore.kernel.org/r/20240910-trust-tbt-fix-v5-1-7a7a42a5f496@chromium.org Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Esther Shimanovich <eshimanovich@chromium.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Tested-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
2024-11-06ACPI: processor: Move arch_init_invariance_cppc() call laterMario Limonciello
arch_init_invariance_cppc() is called at the end of acpi_cppc_processor_probe() in order to configure frequency invariance based upon the values from _CPC. This however doesn't work on AMD CPPC shared memory designs that have AMD preferred cores enabled because _CPC needs to be analyzed from all cores to judge if preferred cores are enabled. This issue manifests to users as a warning since commit 21fb59ab4b97 ("ACPI: CPPC: Adjust debug messages in amd_set_max_freq_ratio() to warn"): ``` Could not retrieve highest performance (-19) ``` However the warning isn't the cause of this, it was actually commit 279f838a61f9 ("x86/amd: Detect preferred cores in amd_get_boost_ratio_numerator()") which exposed the issue. To fix this problem, change arch_init_invariance_cppc() into a new weak symbol that is called at the end of acpi_processor_driver_init(). Each architecture that supports it can declare the symbol to override the weak one. Define it for x86, in arch/x86/kernel/acpi/cppc.c, and for all of the architectures using the generic arch_topology.c code. Fixes: 279f838a61f9 ("x86/amd: Detect preferred cores in amd_get_boost_ratio_numerator()") Reported-by: Ivan Shapovalov <intelfx@intelfx.name> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219431 Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Link: https://patch.msgid.link/20241104222855.3959267-1-superm1@kernel.org [ rjw: Changelog edit ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-11-06fs/xattr: add *at family syscallsChristian Göttsche
Add the four syscalls setxattrat(), getxattrat(), listxattrat() and removexattrat(). Those can be used to operate on extended attributes, especially security related ones, either relative to a pinned directory or on a file descriptor without read access, avoiding a /proc/<pid>/fd/<fd> detour, requiring a mounted procfs. One use case will be setfiles(8) setting SELinux file contexts ("security.selinux") without race conditions and without a file descriptor opened with read access requiring SELinux read permission. Use the do_{name}at() pattern from fs/open.c. Pass the value of the extended attribute, its length, and for setxattrat(2) the command (XATTR_CREATE or XATTR_REPLACE) via an added struct xattr_args to not exceed six syscall arguments and not merging the AT_* and XATTR_* flags. [AV: fixes by Christian Brauner folded in, the entire thing rebased on top of {filename,file}_...xattr() primitives, treatment of empty pathnames regularized. As the result, AT_EMPTY_PATH+NULL handling is cheap, so f...(2) can use it] Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Link: https://lore.kernel.org/r/20240426162042.191916-1-cgoettsche@seltendoof.de Reviewed-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christian Brauner <brauner@kernel.org> CC: x86@kernel.org CC: linux-alpha@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: linux-arm-kernel@lists.infradead.org CC: linux-ia64@vger.kernel.org CC: linux-m68k@lists.linux-m68k.org CC: linux-mips@vger.kernel.org CC: linux-parisc@vger.kernel.org CC: linuxppc-dev@lists.ozlabs.org CC: linux-s390@vger.kernel.org CC: linux-sh@vger.kernel.org CC: sparclinux@vger.kernel.org CC: linux-fsdevel@vger.kernel.org CC: audit@vger.kernel.org CC: linux-arch@vger.kernel.org CC: linux-api@vger.kernel.org CC: linux-security-module@vger.kernel.org CC: selinux@vger.kernel.org [brauner: slight tweaks] Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-11-07x86/kprobes: Cleanup kprobes on ftrace codeMasami Hiramatsu (Google)
Cleanup kprobes on ftrace code for x86. - Set instruction pointer (ip + MCOUNT_INSN_SIZE) after pre_handler only when p->post_handler exists. - Use INT3_INSN_SIZE instead of 1. - Use instruction_pointer/instruction_pointer_set() functions instead of accessing regs->ip directly. Link: https://lore.kernel.org/all/172951436219.167263.18330240454389154327.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-11-06Merge tag 'perf-core-for-bpf-next' from tip treeAndrii Nakryiko
Stable tag for bpf-next's uprobe work. Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2024-11-06m68k: mvme147: Reinstate early consoleDaniel Palmer
Commit a38eaa07a0ce ("m68k/mvme147: config.c - Remove unused functions"), removed the console functionality for the mvme147 instead of wiring it up to an early console. Put the console write function back and wire it up like mvme16x does so it's possible to see Linux boot on this fine hardware once more. Fixes: a38eaa07a0ce ("m68k/mvme147: config.c - Remove unused functions") Signed-off-by: Daniel Palmer <daniel@0x0f.com> Co-developed-by: Finn Thain <fthain@linux-m68k.org> Signed-off-by: Finn Thain <fthain@linux-m68k.org> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/a82e8f0068a8722996a0ccfe666abb5e0a5c120d.1730850684.git.fthain@linux-m68k.org Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2024-11-06m68k: Make sure NR_IRQS is never zeroGeert Uytterhoeven
When compiling an MMU kernel without any platform support, e.g. "MMU=y allnoconfig": echo CONFIG_MMU=y > allno.config make KCONFIG_ALLCONFIG=1 allnoconfig NR_IRQS is zero, causing a build failure: kernel/irq/irqdesc.c:593:3: error: array index in initializer exceeds array bounds 593 | [0 ... NR_IRQS-1] = { | ^ kernel/irq/irqdesc.c:593:3: note: (near initialization for ‘irq_desc’) kernel/irq/irqdesc.c:593:22: warning: excess elements in array initializer 593 | [0 ... NR_IRQS-1] = { | ^ kernel/irq/irqdesc.c:593:22: note: (near initialization for ‘irq_desc’) Fix this by setting the default value of NR_IRQS to 8, which is the mininum number of interrupts on any m68k CPU (the DIP48 variant of the MC68008 has tied IPL0 and IPL2 together, but that does not impact the range). Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/71db70dc27b46e5326518cd23cb94fa6bee172fe.1730805216.git.geert@linux-m68k.org
2024-11-06m68k: Select M68020 as fallback for classicArnd Bergmann
Building without a CPU selected does not work. Change the Kconfig logic slightly to make sure we always pick M68020 if nothing else is enabled. There are still some intentional warnings for builds with all platforms disabled. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/20241030195638.22542-2-arnd@kernel.org Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2024-11-06m68k: Move Sun 3 into a top-level platform optionArnd Bergmann
It is possible to select an m68k MMU build but not actually enable any of the three MMU options, which then results in a build failure: arch/m68k/include/asm/page.h:10:25: error: 'CONFIG_PAGE_SHIFT' undeclared here (not in a function); did you mean 'CONFIG_LOG_BUF_SHIFT'? Change the Kconfig selection to ensure that exactly one of the three options is always enabled whenever an MMU-enabled kernel is built, but moving CONFIG_SUN3 into a top-level option next to M68KCLASSIC and COLDFIRE. All defconfig files should keep working without changes, but alldefconfig now builds support for the classic MMU. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202408032138.P7sBvIns-lkp@intel.com/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Ungerer <gerg@linux-m68k.org> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/20241030195638.22542-1-arnd@kernel.org Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2024-11-06m68k: kernel: Use str_read_write() helper functionThorsten Blum
Remove hard-coded strings by using the str_read_write() helper function and remove some unnecessary negations. Compile-tested only. Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/20241020205758.332095-1-thorsten.blum@linux.dev Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2024-11-06m68k: Initialize jump labels early during setup_arch()Jean-Michel Hautbois
When using static keys early, e.g. by specifying "thread_backlog_napi" on the kernel command line: WARNING: CPU: 0 PID: 0 at include/linux/jump_label.h:322 setup_backlog_napi_threads+0x40/0xa0 static_key_enable(): static key '0x5ceec0' used before call to jump_label_init() The function jump_label_init() should be called from setup_arch() very early for proper functioning of jump label support. Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/20241016-fix-jump-label-v1-1-eb74c5f68405@yoseli.org [geert: Add reproducer] Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2024-11-06m68k: mvme147: Fix SCSI controller IRQ numbersDaniel Palmer
Sometime long ago the m68k IRQ code was refactored and the interrupt numbers for SCSI controller on this board ended up wrong, and it hasn't worked since. The PCC adds 0x40 to the vector for its interrupts so they end up in the user interrupt range. Hence, the kernel number should be the kernel offset for user interrupt range + the PCC interrupt number. Fixes: 200a3d352cd5 ("[PATCH] m68k: convert VME irq code") Signed-off-by: Daniel Palmer <daniel@0x0f.com> Reviewed-by: Finn Thain <fthain@linux-m68k.org> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/0e7636a21a0274eea35bfd5d874459d5078e97cc.1727926187.git.fthain@linux-m68k.org Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2024-11-06m68k: mvme147: Make mvme147_sched_init() __initDaniel Palmer
mvme147_sched_init() is only used once at init time so it can be made __init and save a few bytes of memory. Signed-off-by: Daniel Palmer <daniel@0x0f.com> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/20240929025506.1212237-1-daniel@0x0f.com Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2024-11-06arm64/sve: Discard stale CPU state when handling SVE trapsMark Brown
The logic for handling SVE traps manipulates saved FPSIMD/SVE state incorrectly, and a race with preemption can result in a task having TIF_SVE set and TIF_FOREIGN_FPSTATE clear even though the live CPU state is stale (e.g. with SVE traps enabled). This has been observed to result in warnings from do_sve_acc() where SVE traps are not expected while TIF_SVE is set: | if (test_and_set_thread_flag(TIF_SVE)) | WARN_ON(1); /* SVE access shouldn't have trapped */ Warnings of this form have been reported intermittently, e.g. https://lore.kernel.org/linux-arm-kernel/CA+G9fYtEGe_DhY2Ms7+L7NKsLYUomGsgqpdBj+QwDLeSg=JhGg@mail.gmail.com/ https://lore.kernel.org/linux-arm-kernel/000000000000511e9a060ce5a45c@google.com/ The race can occur when the SVE trap handler is preempted before and after manipulating the saved FPSIMD/SVE state, starting and ending on the same CPU, e.g. | void do_sve_acc(unsigned long esr, struct pt_regs *regs) | { | // Trap on CPU 0 with TIF_SVE clear, SVE traps enabled | // task->fpsimd_cpu is 0. | // per_cpu_ptr(&fpsimd_last_state, 0) is task. | | ... | | // Preempted; migrated from CPU 0 to CPU 1. | // TIF_FOREIGN_FPSTATE is set. | | get_cpu_fpsimd_context(); | | if (test_and_set_thread_flag(TIF_SVE)) | WARN_ON(1); /* SVE access shouldn't have trapped */ | | sve_init_regs() { | if (!test_thread_flag(TIF_FOREIGN_FPSTATE)) { | ... | } else { | fpsimd_to_sve(current); | current->thread.fp_type = FP_STATE_SVE; | } | } | | put_cpu_fpsimd_context(); | | // Preempted; migrated from CPU 1 to CPU 0. | // task->fpsimd_cpu is still 0 | // If per_cpu_ptr(&fpsimd_last_state, 0) is still task then: | // - Stale HW state is reused (with SVE traps enabled) | // - TIF_FOREIGN_FPSTATE is cleared | // - A return to userspace skips HW state restore | } Fix the case where the state is not live and TIF_FOREIGN_FPSTATE is set by calling fpsimd_flush_task_state() to detach from the saved CPU state. This ensures that a subsequent context switch will not reuse the stale CPU state, and will instead set TIF_FOREIGN_FPSTATE, forcing the new state to be reloaded from memory prior to a return to userspace. Fixes: cccb78ce89c4 ("arm64/sve: Rework SVE access trap to convert state in registers") Reported-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org Reviewed-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20241030-arm64-fpsimd-foreign-flush-v1-1-bd7bd66905a2@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2024-11-06kbuild: Add AutoFDO support for Clang buildRong Xu
Add the build support for using Clang's AutoFDO. Building the kernel with AutoFDO does not reduce the optimization level from the compiler. AutoFDO uses hardware sampling to gather information about the frequency of execution of different code paths within a binary. This information is then used to guide the compiler's optimization decisions, resulting in a more efficient binary. Experiments showed that the kernel can improve up to 10% in latency. The support requires a Clang compiler after LLVM 17. This submission is limited to x86 platforms that support PMU features like LBR on Intel machines and AMD Zen3 BRS. Support for SPE on ARM 1, and BRBE on ARM 1 is part of planned future work. Here is an example workflow for AutoFDO kernel: 1) Build the kernel on the host machine with LLVM enabled, for example, $ make menuconfig LLVM=1 Turn on AutoFDO build config: CONFIG_AUTOFDO_CLANG=y With a configuration that has LLVM enabled, use the following command: scripts/config -e AUTOFDO_CLANG After getting the config, build with $ make LLVM=1 2) Install the kernel on the test machine. 3) Run the load tests. The '-c' option in perf specifies the sample event period. We suggest using a suitable prime number, like 500009, for this purpose. For Intel platforms: $ perf record -e BR_INST_RETIRED.NEAR_TAKEN:k -a -N -b -c <count> \ -o <perf_file> -- <loadtest> For AMD platforms: The supported system are: Zen3 with BRS, or Zen4 with amd_lbr_v2 For Zen3: $ cat proc/cpuinfo | grep " brs" For Zen4: $ cat proc/cpuinfo | grep amd_lbr_v2 $ perf record --pfm-events RETIRED_TAKEN_BRANCH_INSTRUCTIONS:k -a \ -N -b -c <count> -o <perf_file> -- <loadtest> 4) (Optional) Download the raw perf file to the host machine. 5) To generate an AutoFDO profile, two offline tools are available: create_llvm_prof and llvm_profgen. The create_llvm_prof tool is part of the AutoFDO project and can be found on GitHub (https://github.com/google/autofdo), version v0.30.1 or later. The llvm_profgen tool is included in the LLVM compiler itself. It's important to note that the version of llvm_profgen doesn't need to match the version of Clang. It needs to be the LLVM 19 release or later, or from the LLVM trunk. $ llvm-profgen --kernel --binary=<vmlinux> --perfdata=<perf_file> \ -o <profile_file> or $ create_llvm_prof --binary=<vmlinux> --profile=<perf_file> \ --format=extbinary --out=<profile_file> Note that multiple AutoFDO profile files can be merged into one via: $ llvm-profdata merge -o <profile_file> <profile_1> ... <profile_n> 6) Rebuild the kernel using the AutoFDO profile file with the same config as step 1, (Note CONFIG_AUTOFDO_CLANG needs to be enabled): $ make LLVM=1 CLANG_AUTOFDO_PROFILE=<profile_file> Co-developed-by: Han Shen <shenhan@google.com> Signed-off-by: Han Shen <shenhan@google.com> Signed-off-by: Rong Xu <xur@google.com> Suggested-by: Sriraman Tallam <tmsriram@google.com> Suggested-by: Krzysztof Pszeniczny <kpszeniczny@google.com> Suggested-by: Nick Desaulniers <ndesaulniers@google.com> Suggested-by: Stephane Eranian <eranian@google.com> Tested-by: Yonghong Song <yonghong.song@linux.dev> Tested-by: Yabin Cui <yabinc@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Tested-by: Peter Jung <ptr1337@cachyos.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>