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2024-04-30x86/irq: Factor out common code for checking pending interruptsJacob Pan2-6/+4
Use a common function for checking pending interrupt vector in APIC IRR instead of duplicated open coding them. Additional checks for posted MSI vectors can then be contained in this function. Signed-off-by: Jacob Pan <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-30x86/irq: Install posted MSI notification handlerJacob Pan2-4/+124
All MSI vectors are multiplexed into a single notification vector when posted MSI is enabled. It is the responsibility of the notification vector handler to demultiplex MSI vectors. In the handler the MSI vector handlers are dispatched without IDT delivery for each pending MSI interrupt. For example, the interrupt flow will change as follows: (3 MSIs of different vectors arrive in a a high frequency burst) BEFORE: interrupt(MSI) irq_enter() handler() /* EOI */ irq_exit() process_softirq() interrupt(MSI) irq_enter() handler() /* EOI */ irq_exit() process_softirq() interrupt(MSI) irq_enter() handler() /* EOI */ irq_exit() process_softirq() AFTER: interrupt /* Posted MSI notification vector */ irq_enter() atomic_xchg(PIR) handler() handler() handler() pi_clear_on() apic_eoi() irq_exit() process_softirq() Except for the leading MSI, CPU notifications are skipped/coalesced. For MSIs which arrive at a low frequency, the demultiplexing loop does not wait for more interrupts to coalesce. Therefore, there's no additional latency other than the processing time. Signed-off-by: Jacob Pan <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-30x86/irq: Factor out handler invocation from common_interrupt()Jacob Pan1-9/+14
Prepare for calling external interrupt handlers directly from the posted MSI demultiplexing loop. Extract the common code from common_interrupt() to avoid code duplication. Signed-off-by: Jacob Pan <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-30x86/irq: Set up per host CPU posted interrupt descriptorsJacob Pan2-0/+26
To support posted MSIs, create a posted interrupt descriptor (PID) for each host CPU. Later on, when setting up interrupt affinity, the IOMMU's interrupt remapping table entry (IRTE) will point to the physical address of the matching CPU's PID. Each PID is initialized with the owner CPU's physical APICID as the destination. Originally-by: Thomas Gleixner <[email protected]> Signed-off-by: Jacob Pan <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-29x86/tsc: Trust initial offset in architectural TSC-adjust MSRsDaniel J Blueman1-4/+2
When the BIOS configures the architectural TSC-adjust MSRs on secondary sockets to correct a constant inter-chassis offset, after Linux brings the cores online, the TSC sync check later resets the core-local MSR to 0, triggering HPET fallback and leading to performance loss. Fix this by unconditionally using the initial adjust values read from the MSRs. Trusting the initial offsets in this architectural mechanism is a better approach than special-casing workarounds for specific platforms. Signed-off-by: Daniel J Blueman <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Steffen Persvold <[email protected]> Reviewed-by: James Cleverdon <[email protected]> Reviewed-by: Dimitri Sivanich <[email protected]> Reviewed-by: Prarit Bhargava <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-29x86/e820: Add a new e820 table update helperAshish Kalra1-3/+4
Add a new API helper e820__range_update_table() with which to update an arbitrary e820 table. Move all current users of e820__range_update_kexec() to this new helper. [ bp: Massage. ] Signed-off-by: Ashish Kalra <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/r/b726af213ad55053f8a7a1e793b01bb3f1ca9dd5.1714090302.git.ashish.kalra@amd.com
2024-04-29x86/tsc_msr: Switch to new Intel CPU model definesTony Luck1-7/+7
New CPU #defines encode vendor and family as well as model. Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/all/20240424181518.41927-1-tony.luck%40intel.com
2024-04-29x86/tsc: Switch to new Intel CPU model definesTony Luck1-3/+3
New CPU #defines encode vendor and family as well as model. Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/all/20240424181517.41907-1-tony.luck%40intel.com
2024-04-29x86/cpu: Switch to new Intel CPU model definesTony Luck1-3/+3
New CPU #defines encode vendor and family as well as model. [ dhansen: vertically align macro and remove stray subject / ] Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/all/20240424181516.41887-1-tony.luck%40intel.com
2024-04-29x86/resctrl: Switch to new Intel CPU model definesTony Luck2-16/+16
New CPU #defines encode vendor and family as well as model. [ bp: Squash two resctrl patches into one. ] Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/all/20240424181514.41848-1-tony.luck%40intel.com
2024-04-29x86/microcode/intel: Switch to new Intel CPU model definesTony Luck1-3/+2
New CPU #defines encode vendor and family as well as model. Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/all/20240424181513.41829-1-tony.luck%40intel.com
2024-04-29x86/mce: Switch to new Intel CPU model definesTony Luck3-19/+18
New CPU #defines encode vendor and family as well as model. [ bp: Squash *three* mce patches into one, fold in fix: https://lore.kernel.org/r/[email protected] ] Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/all/20240424181511.41772-1-tony.luck%40intel.com
2024-04-29x86/cpu: Switch to new Intel CPU model definesTony Luck1-1/+1
New CPU #defines encode vendor and family as well as model. Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/all/20240424181511.41753-1-tony.luck%40intel.com
2024-04-29x86/cpu/intel_epb: Switch to new Intel CPU model definesTony Luck1-6/+6
New CPU #defines encode vendor and family as well as model. Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/all/20240424181510.41733-1-tony.luck%40intel.com
2024-04-29x86/aperfmperf: Switch to new Intel CPU model definesTony Luck1-9/+8
New CPU #defines encode vendor and family as well as model. Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/all/20240424181505.41654-1-tony.luck%40intel.com
2024-04-29x86/apic: Switch to new Intel CPU model definesTony Luck1-19/+19
New CPU #defines encode vendor and family as well as model. Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/all/20240424181504.41634-1-tony.luck%40intel.com
2024-04-25x86/mm: care about shadow stack guard gap during placementRick Edgecombe1-0/+10
When memory is being placed, mmap() will take care to respect the guard gaps of certain types of memory (VM_SHADOWSTACK, VM_GROWSUP and VM_GROWSDOWN). In order to ensure guard gaps between mappings, mmap() needs to consider two things: 1. That the new mapping isn't placed in an any existing mappings guard gaps. 2. That the new mapping isn't placed such that any existing mappings are not in *its* guard gaps. The longstanding behavior of mmap() is to ensure 1, but not take any care around 2. So for example, if there is a PAGE_SIZE free area, and a mmap() with a PAGE_SIZE size, and a type that has a guard gap is being placed, mmap() may place the shadow stack in the PAGE_SIZE free area. Then the mapping that is supposed to have a guard gap will not have a gap to the adjacent VMA. Now that the vm_flags is passed into the arch get_unmapped_area()'s, and vm_unmapped_area() is ready to consider it, have VM_SHADOW_STACK's get guard gap consideration for scenario 2. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Rick Edgecombe <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Aneesh Kumar K.V <[email protected]> Cc: Borislav Petkov (AMD) <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Dan Williams <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Deepak Gupta <[email protected]> Cc: Guo Ren <[email protected]> Cc: Helge Deller <[email protected]> Cc: H. Peter Anvin (Intel) <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Kees Cook <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Liam R. Howlett <[email protected]> Cc: Mark Brown <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Naveen N. Rao <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-04-25x86/mm: implement HAVE_ARCH_UNMAPPED_AREA_VMFLAGSRick Edgecombe1-5/+20
When memory is being placed, mmap() will take care to respect the guard gaps of certain types of memory (VM_SHADOWSTACK, VM_GROWSUP and VM_GROWSDOWN). In order to ensure guard gaps between mappings, mmap() needs to consider two things: 1. That the new mapping isn't placed in an any existing mappings guard gaps. 2. That the new mapping isn't placed such that any existing mappings are not in *its* guard gaps. The longstanding behavior of mmap() is to ensure 1, but not take any care around 2. So for example, if there is a PAGE_SIZE free area, and a mmap() with a PAGE_SIZE size, and a type that has a guard gap is being placed, mmap() may place the shadow stack in the PAGE_SIZE free area. Then the mapping that is supposed to have a guard gap will not have a gap to the adjacent VMA. Add x86 arch implementations of arch_get_unmapped_area_vmflags/_topdown() so future changes can allow the guard gap of type of vma being placed to be taken into account. This will be used for shadow stack memory. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Rick Edgecombe <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Aneesh Kumar K.V <[email protected]> Cc: Borislav Petkov (AMD) <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Dan Williams <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Deepak Gupta <[email protected]> Cc: Guo Ren <[email protected]> Cc: Helge Deller <[email protected]> Cc: H. Peter Anvin (Intel) <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Kees Cook <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Liam R. Howlett <[email protected]> Cc: Mark Brown <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Naveen N. Rao <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-04-25treewide: use initializer for struct vm_unmapped_area_infoRick Edgecombe1-5/+2
Future changes will need to add a new member to struct vm_unmapped_area_info. This would cause trouble for any call site that doesn't initialize the struct. Currently every caller sets each member manually, so if new ones are added they will be uninitialized and the core code parsing the struct will see garbage in the new member. It could be possible to initialize the new member manually to 0 at each call site. This and a couple other options were discussed. Having some struct vm_unmapped_area_info instances not zero initialized will put those sites at risk of feeding garbage into vm_unmapped_area(), if the convention is to zero initialize the struct and any new field addition missed a call site that initializes each field manually. So it is useful to do things similar across the kernel. The consensus (see links) was that in general the best way to accomplish taking into account both code cleanliness and minimizing the chance of introducing bugs, was to do C99 static initialization. As in: struct vm_unmapped_area_info info = {}; With this method of initialization, the whole struct will be zero initialized, and any statements setting fields to zero will be unneeded. The change should not leave cleanup at the call sides. While iterating though the possible solutions a few archs kindly acked other variations that still zero initialized the struct. These sites have been modified in previous changes using the pattern acked by the respective arch. So to be reduce the chance of bugs via uninitialized fields, perform a tree wide change using the consensus for the best general way to do this change. Use C99 static initializing to zero the struct and remove and statements that simply set members to zero. Link: https://lkml.kernel.org/r/[email protected] Link: https://lore.kernel.org/lkml/202402280912.33AEE7A9CF@keescook/#t Link: https://lore.kernel.org/lkml/j7bfvig3gew3qruouxrh7z7ehjjafrgkbcmg6tcghhfh3rhmzi@wzlcoecgy5rs/ Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Rick Edgecombe <[email protected]> Reviewed-by: Kees Cook <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Aneesh Kumar K.V <[email protected]> Cc: Borislav Petkov (AMD) <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Dan Williams <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Deepak Gupta <[email protected]> Cc: Guo Ren <[email protected]> Cc: Helge Deller <[email protected]> Cc: H. Peter Anvin (Intel) <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Liam R. Howlett <[email protected]> Cc: Mark Brown <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Naveen N. Rao <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-04-25mm: switch mm->get_unmapped_area() to a flagRick Edgecombe1-1/+1
The mm_struct contains a function pointer *get_unmapped_area(), which is set to either arch_get_unmapped_area() or arch_get_unmapped_area_topdown() during the initialization of the mm. Since the function pointer only ever points to two functions that are named the same across all arch's, a function pointer is not really required. In addition future changes will want to add versions of the functions that take additional arguments. So to save a pointers worth of bytes in mm_struct, and prevent adding additional function pointers to mm_struct in future changes, remove it and keep the information about which get_unmapped_area() to use in a flag. Add the new flag to MMF_INIT_MASK so it doesn't get clobbered on fork by mmf_init_flags(). Most MM flags get clobbered on fork. In the pre-existing behavior mm->get_unmapped_area() would get copied to the new mm in dup_mm(), so not clobbering the flag preserves the existing behavior around inheriting the topdown-ness. Introduce a helper, mm_get_unmapped_area(), to easily convert code that refers to the old function pointer to instead select and call either arch_get_unmapped_area() or arch_get_unmapped_area_topdown() based on the flag. Then drop the mm->get_unmapped_area() function pointer. Leave the get_unmapped_area() pointer in struct file_operations alone. The main purpose of this change is to reorganize in preparation for future changes, but it also converts the calls of mm->get_unmapped_area() from indirect branches into a direct ones. The stress-ng bigheap benchmark calls realloc a lot, which calls through get_unmapped_area() in the kernel. On x86, the change yielded a ~1% improvement there on a retpoline config. In testing a few x86 configs, removing the pointer unfortunately didn't result in any actual size reductions in the compiled layout of mm_struct. But depending on compiler or arch alignment requirements, the change could shrink the size of mm_struct. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Rick Edgecombe <[email protected]> Acked-by: Dave Hansen <[email protected]> Acked-by: Liam R. Howlett <[email protected]> Reviewed-by: Kirill A. Shutemov <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Cc: Dan Williams <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Aneesh Kumar K.V <[email protected]> Cc: Borislav Petkov (AMD) <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Deepak Gupta <[email protected]> Cc: Guo Ren <[email protected]> Cc: Helge Deller <[email protected]> Cc: H. Peter Anvin (Intel) <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Kees Cook <[email protected]> Cc: Mark Brown <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Naveen N. Rao <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-04-25x86: remove unneeded memblock_find_dma_reserve()Baoquan He1-2/+0
Patch series "mm/mm_init.c: refactor free_area_init_core()". In function free_area_init_core(), the code calculating zone->managed_pages and the subtracting dma_reserve from DMA zone looks very confusing. From git history, the code calculating zone->managed_pages was for zone->present_pages originally. The early rough assignment is for optimize zone's pcp and water mark setting. Later, managed_pages was introduced into zone to represent the number of managed pages by buddy. Now, zone->managed_pages is zeroed out and reset in mem_init() when calling memblock_free_all(). zone's pcp and wmark setting relying on actual zone->managed_pages are done later than mem_init() invocation. So we don't need rush to early calculate and set zone->managed_pages, just set it as zone->present_pages, will adjust it in mem_init(). And also add a new function calc_nr_kernel_pages() to count up free but not reserved pages in memblock, then assign it to nr_all_pages and nr_kernel_pages after memmap pages are allocated. This patch (of 6): Variable dma_reserve and its usage was introduced in commit 0e0b864e069c ("[PATCH] Account for memmap and optionally the kernel image as holes"). Its original purpose was to accounting for the reserved pages in DMA zone to make DMA zone's watermarks calculation more accurate on x86. However, currently there's zone->managed_pages to account for all available pages for buddy, zone->present_pages to account for all present physical pages in zone. What is more important, on x86, calculating and setting the zone->managed_pages is a temporary move, all zone's managed_pages will be zeroed out and reset to the actual value according to how many pages are added to buddy allocator in mem_init(). Before mem_init(), no buddy alloction is requested. And zone's pcp and watermark setting are all done after mem_init(). So, no need to worry about the DMA zone's setting accuracy during free_area_init(). Hence, remove memblock_find_dma_reserve() to stop calculating and setting dma_reserve. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Baoquan He <[email protected]> Reviewed-by: Mike Rapoport (IBM) <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-04-25change alloc_pages name in dma_map_ops to avoid name conflictsSuren Baghdasaryan1-1/+1
After redefining alloc_pages, all uses of that name are being replaced. Change the conflicting names to prevent preprocessor from replacing them when it's not intended. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Suren Baghdasaryan <[email protected]> Tested-by: Kees Cook <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Alex Gaynor <[email protected]> Cc: Alice Ryhl <[email protected]> Cc: Andreas Hindborg <[email protected]> Cc: Benno Lossin <[email protected]> Cc: "Björn Roy Baron" <[email protected]> Cc: Boqun Feng <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Dennis Zhou <[email protected]> Cc: Gary Guo <[email protected]> Cc: Kent Overstreet <[email protected]> Cc: Miguel Ojeda <[email protected]> Cc: Pasha Tatashin <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Tejun Heo <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Wedson Almeida Filho <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-04-25fix missing vmalloc.h includesKent Overstreet2-0/+2
Patch series "Memory allocation profiling", v6. Overview: Low overhead [1] per-callsite memory allocation profiling. Not just for debug kernels, overhead low enough to be deployed in production. Example output: root@moria-kvm:~# sort -rn /proc/allocinfo 127664128 31168 mm/page_ext.c:270 func:alloc_page_ext 56373248 4737 mm/slub.c:2259 func:alloc_slab_page 14880768 3633 mm/readahead.c:247 func:page_cache_ra_unbounded 14417920 3520 mm/mm_init.c:2530 func:alloc_large_system_hash 13377536 234 block/blk-mq.c:3421 func:blk_mq_alloc_rqs 11718656 2861 mm/filemap.c:1919 func:__filemap_get_folio 9192960 2800 kernel/fork.c:307 func:alloc_thread_stack_node 4206592 4 net/netfilter/nf_conntrack_core.c:2567 func:nf_ct_alloc_hashtable 4136960 1010 drivers/staging/ctagmod/ctagmod.c:20 [ctagmod] func:ctagmod_start 3940352 962 mm/memory.c:4214 func:alloc_anon_folio 2894464 22613 fs/kernfs/dir.c:615 func:__kernfs_new_node ... Usage: kconfig options: - CONFIG_MEM_ALLOC_PROFILING - CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT - CONFIG_MEM_ALLOC_PROFILING_DEBUG adds warnings for allocations that weren't accounted because of a missing annotation sysctl: /proc/sys/vm/mem_profiling Runtime info: /proc/allocinfo Notes: [1]: Overhead To measure the overhead we are comparing the following configurations: (1) Baseline with CONFIG_MEMCG_KMEM=n (2) Disabled by default (CONFIG_MEM_ALLOC_PROFILING=y && CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=n) (3) Enabled by default (CONFIG_MEM_ALLOC_PROFILING=y && CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=y) (4) Enabled at runtime (CONFIG_MEM_ALLOC_PROFILING=y && CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=n && /proc/sys/vm/mem_profiling=1) (5) Baseline with CONFIG_MEMCG_KMEM=y && allocating with __GFP_ACCOUNT (6) Disabled by default (CONFIG_MEM_ALLOC_PROFILING=y && CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=n) && CONFIG_MEMCG_KMEM=y (7) Enabled by default (CONFIG_MEM_ALLOC_PROFILING=y && CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=y) && CONFIG_MEMCG_KMEM=y Performance overhead: To evaluate performance we implemented an in-kernel test executing multiple get_free_page/free_page and kmalloc/kfree calls with allocation sizes growing from 8 to 240 bytes with CPU frequency set to max and CPU affinity set to a specific CPU to minimize the noise. Below are results from running the test on Ubuntu 22.04.2 LTS with 6.8.0-rc1 kernel on 56 core Intel Xeon: kmalloc pgalloc (1 baseline) 6.764s 16.902s (2 default disabled) 6.793s (+0.43%) 17.007s (+0.62%) (3 default enabled) 7.197s (+6.40%) 23.666s (+40.02%) (4 runtime enabled) 7.405s (+9.48%) 23.901s (+41.41%) (5 memcg) 13.388s (+97.94%) 48.460s (+186.71%) (6 def disabled+memcg) 13.332s (+97.10%) 48.105s (+184.61%) (7 def enabled+memcg) 13.446s (+98.78%) 54.963s (+225.18%) Memory overhead: Kernel size: text data bss dec diff (1) 26515311 18890222 17018880 62424413 (2) 26524728 19423818 16740352 62688898 264485 (3) 26524724 19423818 16740352 62688894 264481 (4) 26524728 19423818 16740352 62688898 264485 (5) 26541782 18964374 16957440 62463596 39183 Memory consumption on a 56 core Intel CPU with 125GB of memory: Code tags: 192 kB PageExts: 262144 kB (256MB) SlabExts: 9876 kB (9.6MB) PcpuExts: 512 kB (0.5MB) Total overhead is 0.2% of total memory. Benchmarks: Hackbench tests run 100 times: hackbench -s 512 -l 200 -g 15 -f 25 -P baseline disabled profiling enabled profiling avg 0.3543 0.3559 (+0.0016) 0.3566 (+0.0023) stdev 0.0137 0.0188 0.0077 hackbench -l 10000 baseline disabled profiling enabled profiling avg 6.4218 6.4306 (+0.0088) 6.5077 (+0.0859) stdev 0.0933 0.0286 0.0489 stress-ng tests: stress-ng --class memory --seq 4 -t 60 stress-ng --class cpu --seq 4 -t 60 Results posted at: https://evilpiepirate.org/~kent/memalloc_prof_v4_stress-ng/ [2] https://lore.kernel.org/all/[email protected]/ This patch (of 37): The next patch drops vmalloc.h from a system header in order to fix a circular dependency; this adds it to all the files that were pulling it in implicitly. [[email protected]: fix arch/alpha/lib/memcpy.c] Link: https://lkml.kernel.org/r/[email protected] [[email protected]: fix arch/x86/mm/numa_32.c] Link: https://lkml.kernel.org/r/[email protected] [[email protected]: a few places were depending on sizes.h] Link: https://lkml.kernel.org/r/[email protected] [[email protected]: fix mm/kasan/hw_tags.c] Link: https://lkml.kernel.org/r/[email protected] [[email protected]: fix arc build] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kent Overstreet <[email protected]> Signed-off-by: Suren Baghdasaryan <[email protected]> Signed-off-by: Arnd Bergmann <[email protected]> Reviewed-by: Pasha Tatashin <[email protected]> Tested-by: Kees Cook <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Alex Gaynor <[email protected]> Cc: Alice Ryhl <[email protected]> Cc: Andreas Hindborg <[email protected]> Cc: Benno Lossin <[email protected]> Cc: "Björn Roy Baron" <[email protected]> Cc: Boqun Feng <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Dennis Zhou <[email protected]> Cc: Gary Guo <[email protected]> Cc: Miguel Ojeda <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Tejun Heo <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Wedson Almeida Filho <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-04-25x86/sev: Shorten struct name snp_secrets_page_layout to snp_secrets_pageTom Lendacky1-3/+3
Ending a struct name with "layout" is a little redundant, so shorten the snp_secrets_page_layout name to just snp_secrets_page. No functional change. [ bp: Rename the local pointer to "secrets" too for more clarity. ] Signed-off-by: Tom Lendacky <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/r/bc8d58302c6ab66c3beeab50cce3ec2c6bd72d6c.1713974291.git.thomas.lendacky@amd.com
2024-04-25x86/bugs: Switch to new Intel CPU model definesTony Luck1-78/+76
New CPU #defines encode vendor and family as well as model. Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Acked-by: Josh Poimboeuf <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-25x86/bugs: Switch to new Intel CPU model definesTony Luck1-15/+15
New CPU #defines encode vendor and family as well as model. Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Acked-by: Josh Poimboeuf <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-24x86/cpu: Fix check for RDPKRU in __show_regs()David Kaplan1-1/+1
cpu_feature_enabled(X86_FEATURE_OSPKE) does not necessarily reflect whether CR4.PKE is set on the CPU. In particular, they may differ on non-BSP CPUs before setup_pku() is executed. In this scenario, RDPKRU will #UD causing the system to hang. Fix by checking CR4 for PKE enablement which is always correct for the current CPU. The scenario happens by inserting a WARN* before setup_pku() in identiy_cpu() or some other diagnostic which would lead to calling __show_regs(). [ bp: Massage commit message. ] Signed-off-by: David Kaplan <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-24x86/resctrl: Add tracepoint for llc_occupancy trackingHaifeng Xu2-0/+27
In our production environment, after removing monitor groups, those unused RMIDs get stuck in the limbo list forever because their llc_occupancy is always larger than the threshold. But the unused RMIDs can be successfully freed by turning up the threshold. In order to know how much the threshold should be, perf can be used to acquire the llc_occupancy of RMIDs in each rdt domain. Instead of using perf tool to track llc_occupancy and filter the log manually, it is more convenient for users to use tracepoint to do this work. So add a new tracepoint that shows the llc_occupancy of busy RMIDs when scanning the limbo list. Suggested-by: Reinette Chatre <[email protected]> Suggested-by: James Morse <[email protected]> Signed-off-by: Haifeng Xu <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Reviewed-by: James Morse <[email protected]> Reviewed-by: Reinette Chatre <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-24x86/resctrl: Rename pseudo_lock_event.h to trace.hHaifeng Xu2-5/+5
Now only the pseudo-locking part uses tracepoints to do event tracking, but other parts of resctrl may need new tracepoints. It is unnecessary to create separate header files and define CREATE_TRACE_POINTS in different c files which fragments the resctrl tracing. Therefore, give the resctrl tracepoint header file a generic name to support its use for tracepoints that are not specific to pseudo-locking. No functional change. Suggested-by: Reinette Chatre <[email protected]> Signed-off-by: Haifeng Xu <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Reviewed-by: Reinette Chatre <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-24x86/CPU/AMD: Add models 0x10-0x1f to the Zen5 rangeWenkuan Wang1-2/+1
Add some more Zen5 models. Fixes: 3e4147f33f8b ("x86/CPU/AMD: Add X86_FEATURE_ZEN5") Signed-off-by: Wenkuan Wang <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-24x86/resctrl: Simplify call convention for MSR update functionsTony Luck3-27/+18
The per-resource MSR update functions cat_wrmsr(), mba_wrmsr_intel(), and mba_wrmsr_amd() all take three arguments: (struct rdt_domain *d, struct msr_param *m, struct rdt_resource *r) struct msr_param contains pointers to both struct rdt_resource and struct rdt_domain, thus only struct msr_param is necessary. Pass struct msr_param as a single parameter. Clean up formatting and fix some fir tree declaration ordering. No functional change. Suggested-by: Reinette Chatre <[email protected]> Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Reviewed-by: Reinette Chatre <[email protected]> Reviewed-by: Babu Moger <[email protected]> Tested-by: Maciej Wieczor-Retman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-24x86/resctrl: Pass domain to target CPUTony Luck4-52/+17
reset_all_ctrls() and resctrl_arch_update_domains() use on_each_cpu_mask() to call rdt_ctrl_update() on potentially one CPU from each domain. But this means rdt_ctrl_update() needs to figure out which domain to apply changes to. Doing so requires a search of all domains in a resource, which can only be done safely if cpus_lock is held. Both callers do hold this lock, but there isn't a way for a function called on another CPU via IPI to verify this. Commit c0d848fcb09d ("x86/resctrl: Remove lockdep annotation that triggers false positive") removed the incorrect assertions. Add the target domain to the msr_param structure and call rdt_ctrl_update() for each domain separately using smp_call_function_single(). This means that rdt_ctrl_update() doesn't need to search for the domain and get_domain_from_cpu() can safely assert that the cpus_lock is held since the remaining callers do not use IPI. Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Reviewed-by: Reinette Chatre <[email protected]> Reviewed-by: James Morse <[email protected]> Reviewed-by: Babu Moger <[email protected]> Tested-by: Maciej Wieczor-Retman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-23crash: add a new kexec flag for hotplug supportSourabh Jain1-11/+17
Commit a72bbec70da2 ("crash: hotplug support for kexec_load()") introduced a new kexec flag, `KEXEC_UPDATE_ELFCOREHDR`. Kexec tool uses this flag to indicate to the kernel that it is safe to modify the elfcorehdr of the kdump image loaded using the kexec_load system call. However, it is possible that architectures may need to update kexec segments other then elfcorehdr. For example, FDT (Flatten Device Tree) on PowerPC. Introducing a new kexec flag for every new kexec segment may not be a good solution. Hence, a generic kexec flag bit, `KEXEC_CRASH_HOTPLUG_SUPPORT`, is introduced to share the CPU/Memory hotplug support intent between the kexec tool and the kernel for the kexec_load system call. Now we have two kexec flags that enables crash hotplug support for kexec_load system call. First is KEXEC_UPDATE_ELFCOREHDR (only used in x86), and second is KEXEC_CRASH_HOTPLUG_SUPPORT (for all architectures). To simplify the process of finding and reporting the crash hotplug support the following changes are introduced. 1. Define arch specific function to process the kexec flags and determine crash hotplug support 2. Rename the @update_elfcorehdr member of struct kimage to @hotplug_support and populate it for both kexec_load and kexec_file_load syscalls, because architecture can update more than one kexec segment 3. Let generic function crash_check_hotplug_support report hotplug support for loaded kdump image based on value of @hotplug_support To bring the x86 crash hotplug support in line with the above points, the following changes have been made: - Introduce the arch_crash_hotplug_support function to process kexec flags and determine crash hotplug support - Remove the arch_crash_hotplug_[cpu|memory]_support functions Signed-off-by: Sourabh Jain <[email protected]> Acked-by: Baoquan He <[email protected]> Acked-by: Hari Bathini <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://msgid.link/[email protected]
2024-04-23crash: forward memory_notify arg to arch crash hotplug handlerSourabh Jain1-1/+3
In the event of memory hotplug or online/offline events, the crash memory hotplug notifier `crash_memhp_notifier()` receives a `memory_notify` object but doesn't forward that object to the generic and architecture-specific crash hotplug handler. The `memory_notify` object contains the starting PFN (Page Frame Number) and the number of pages in the hot-removed memory. This information is necessary for architectures like PowerPC to update/recreate the kdump image, specifically `elfcorehdr`. So update the function signature of `crash_handle_hotplug_event()` and `arch_crash_handle_hotplug_event()` to accept the `memory_notify` object as an argument from crash memory hotplug notifier. Since no such object is available in the case of CPU hotplug event, the crash CPU hotplug notifier `crash_cpuhp_online()` passes NULL to the crash hotplug handler. Signed-off-by: Sourabh Jain <[email protected]> Acked-by: Baoquan He <[email protected]> Acked-by: Hari Bathini <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://msgid.link/[email protected]
2024-04-22x86/sev: Check for MWAITX and MONITORX opcodes in the #VC handlerTom Lendacky1-2/+4
The MWAITX and MONITORX instructions generate the same #VC error code as the MWAIT and MONITOR instructions, respectively. Update the #VC handler opcode checking to also support the MWAITX and MONITORX opcodes. Fixes: e3ef461af35a ("x86/sev: Harden #VC instruction emulation somewhat") Signed-off-by: Tom Lendacky <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Link: https://lore.kernel.org/r/453d5a7cfb4b9fe818b6fb67f93ae25468bc9e23.1713793161.git.thomas.lendacky@amd.com
2024-04-22x86/cpu/vfm: Update arch/x86/include/asm/intel-family.hTony Luck1-2/+1
New CPU #defines encode vendor and family as well as model. Update the example usage comment in arch/x86/kernel/cpu/match.c Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Reviewed-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-19Merge x86 bugfixes from Linux 6.9-rc3Paolo Bonzini12-68/+65
Pull fix for SEV-SNP late disable bugs. Signed-off-by: Paolo Bonzini <[email protected]>
2024-04-18x86/cpufeatures: Fix dependencies for GFNI, VAES, and VPCLMULQDQEric Biggers1-3/+3
Fix cpuid_deps[] to list the correct dependencies for GFNI, VAES, and VPCLMULQDQ. These features don't depend on AVX512, and there exist CPUs that support these features but not AVX512. GFNI actually doesn't even depend on AVX. This prevents GFNI from being unnecessarily disabled if AVX is disabled to mitigate the GDS vulnerability. This also prevents all three features from being unnecessarily disabled if AVX512VL (or its dependency AVX512F) were to be disabled, but it looks like there isn't any case where this happens anyway. Fixes: c128dbfa0f87 ("x86/cpufeatures: Enable new SSE/AVX/AVX512 CPU features") Signed-off-by: Eric Biggers <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Acked-by: Dave Hansen <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-14x86/bugs: Fix BHI retpoline checkJosh Poimboeuf1-4/+7
Confusingly, X86_FEATURE_RETPOLINE doesn't mean retpolines are enabled, as it also includes the original "AMD retpoline" which isn't a retpoline at all. Also replace cpu_feature_enabled() with boot_cpu_has() because this is before alternatives are patched and cpu_feature_enabled()'s fallback path is slower than plain old boot_cpu_has(). Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Signed-off-by: Josh Poimboeuf <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Reviewed-by: Pawan Gupta <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Linus Torvalds <[email protected]> Link: https://lore.kernel.org/r/ad3807424a3953f0323c011a643405619f2a4927.1712944776.git.jpoimboe@kernel.org
2024-04-12x86/sev: Take NUMA node into account when allocating memory for per-CPU SEV dataLi RongQing1-4/+4
per-CPU SEV data is dominantly accessed from their own local CPUs, so allocate them node-local to improve performance. Signed-off-by: Li RongQing <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Cc: Nikunj A Dadhania <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2024-04-12Merge branch 'x86/urgent' into x86/cpu, to resolve conflictIngo Molnar7-101/+216
There's a new conflict between this commit pending in x86/cpu: 63edbaa48a57 x86/cpu/topology: Add support for the AMD 0x80000026 leaf And these fixes in x86/urgent: c064b536a8f9 x86/cpu/amd: Make the NODEID_MSR union actually work 1b3108f6898e x86/cpu/amd: Make the CPUID 0x80000008 parser correct Resolve them. Conflicts: arch/x86/kernel/cpu/topology_amd.c Signed-off-by: Ingo Molnar <[email protected]>
2024-04-12x86/cpu/amd: Move TOPOEXT enablement into the topology parserThomas Gleixner2-15/+21
The topology rework missed that early_init_amd() tries to re-enable the Topology Extensions when the BIOS disabled them. The new parser is invoked before early_init_amd() so the re-enable attempt happens too late. Move it into the AMD specific topology parser code where it belongs. Fixes: f7fb3b2dd92c ("x86/cpu: Provide an AMD/HYGON specific topology parser") Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Link: https://lore.kernel.org/r/878r1j260l.ffs@tglx
2024-04-12x86/cpu/amd: Make the NODEID_MSR union actually workThomas Gleixner1-3/+3
A system with NODEID_MSR was reported to crash during early boot without any output. The reason is that the union which is used for accessing the bitfields in the MSR is written wrongly and the resulting executable code accesses the wrong part of the MSR data. As a consequence a later division by that value results in 0 and that result is used for another division as divisor, which obviously does not work well. The magic world of C, unions and bitfields: union { u64 bita : 3, bitb : 3; u64 all; } x; x.all = foo(); a = x.bita; b = x.bitb; results in the effective executable code of: a = b = x.bita; because bita and bitb are treated as union members and therefore both end up at bit offset 0. Wrapping the bitfield into an anonymous struct: union { struct { u64 bita : 3, bitb : 3; }; u64 all; } x; works like expected. Rework the NODEID_MSR union in exactly that way to cure the problem. Fixes: f7fb3b2dd92c ("x86/cpu: Provide an AMD/HYGON specific topology parser") Reported-by: "kernelci.org bot" <[email protected]> Reported-by: Laura Nao <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Laura Nao <[email protected]> Link: https://lore.kernel.org/r/[email protected] Closes: https://lore.kernel.org/all/[email protected]/
2024-04-12x86/cpu/amd: Make the CPUID 0x80000008 parser correctThomas Gleixner1-6/+18
CPUID 0x80000008 ECX.cpu_nthreads describes the number of threads in the package. The parser uses this value to initialize the SMT domain level. That's wrong because cpu_nthreads does not describe the number of threads per physical core. So this needs to set the CORE domain level and let the later parsers set the SMT shift if available. Preset the SMT domain level with the assumption of one thread per core, which is correct ifrt here are no other CPUID leafs to parse, and propagate cpu_nthreads and the core level APIC bitwidth into the CORE domain. Fixes: f7fb3b2dd92c ("x86/cpu: Provide an AMD/HYGON specific topology parser") Reported-by: "kernelci.org bot" <[email protected]> Reported-by: Laura Nao <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Laura Nao <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2024-04-12x86/bugs: Replace CONFIG_SPECTRE_BHI_{ON,OFF} with CONFIG_MITIGATION_SPECTRE_BHIJosh Poimboeuf1-1/+1
For consistency with the other CONFIG_MITIGATION_* options, replace the CONFIG_SPECTRE_BHI_{ON,OFF} options with a single CONFIG_MITIGATION_SPECTRE_BHI option. [ mingo: Fix ] Signed-off-by: Josh Poimboeuf <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Cc: Sean Christopherson <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Nikolay Borisov <[email protected]> Link: https://lore.kernel.org/r/3833812ea63e7fdbe36bf8b932e63f70d18e2a2a.1712813475.git.jpoimboe@kernel.org
2024-04-12x86/bugs: Remove CONFIG_BHI_MITIGATION_AUTO and spectre_bhi=autoJosh Poimboeuf1-9/+1
Unlike most other mitigations' "auto" options, spectre_bhi=auto only mitigates newer systems, which is confusing and not particularly useful. Remove it. Signed-off-by: Josh Poimboeuf <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Reviewed-by: Nikolay Borisov <[email protected]> Cc: Sean Christopherson <[email protected]> Cc: Linus Torvalds <[email protected]> Link: https://lore.kernel.org/r/412e9dc87971b622bbbaf64740ebc1f140bff343.1712813475.git.jpoimboe@kernel.org
2024-04-11KVM: SEV: sync FPU and AVX state at LAUNCH_UPDATE_VMSA timePaolo Bonzini2-2/+1
SEV-ES allows passing custom contents for x87, SSE and AVX state into the VMSA. Allow userspace to do that with the usual KVM_SET_XSAVE API and only mark FPU contents as confidential after it has been copied and encrypted into the VMSA. Since the XSAVE state for AVX is the first, it does not need the compacted-state handling of get_xsave_addr(). However, there are other parts of XSAVE state in the VMSA that currently are not handled, and the validation logic of get_xsave_addr() is pointless to duplicate in KVM, so move get_xsave_addr() to public FPU API; it is really just a facility to operate on XSAVE state and does not expose any internal details of arch/x86/kernel/fpu. Acked-by: Dave Hansen <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]> Message-ID: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2024-04-11Merge tag 'v6.9-rc3' into x86/boot, to pick up fixes before queueing up more ↵Ingo Molnar24-201/+185
changes Signed-off-by: Ingo Molnar <[email protected]>
2024-04-11x86/bugs: Clarify that syscall hardening isn't a BHI mitigationJosh Poimboeuf1-3/+3
While syscall hardening helps prevent some BHI attacks, there's still other low-hanging fruit remaining. Don't classify it as a mitigation and make it clear that the system may still be vulnerable if it doesn't have a HW or SW mitigation enabled. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Signed-off-by: Josh Poimboeuf <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Sean Christopherson <[email protected]> Link: https://lore.kernel.org/r/b5951dae3fdee7f1520d5136a27be3bdfe95f88b.1712813475.git.jpoimboe@kernel.org
2024-04-11x86/bugs: Fix BHI handling of RRSBAJosh Poimboeuf1-12/+18
The ARCH_CAP_RRSBA check isn't correct: RRSBA may have already been disabled by the Spectre v2 mitigation (or can otherwise be disabled by the BHI mitigation itself if needed). In that case retpolines are fine. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Signed-off-by: Josh Poimboeuf <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Sean Christopherson <[email protected]> Link: https://lore.kernel.org/r/6f56f13da34a0834b69163467449be7f58f253dc.1712813475.git.jpoimboe@kernel.org