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2025-05-21x86/xen/msr: Fix uninitialized variable 'err'Xin Li (Intel)
xen_read_msr_safe() currently passes an uninitialized argument 'err' to xen_do_read_msr(). But as xen_do_read_msr() may not set the argument, xen_read_msr_safe() could return err with an unpredictable value. To ensure correctness, initialize err to 0 (representing success) in xen_read_msr_safe(). Do the same in xen_read_msr(), even err is not used after being passed to xen_do_read_msr(). Closes: https://lore.kernel.org/xen-devel/aBxNI_Q0-MhtBSZG@stanley.mountain/ Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Xin Li (Intel) <xin@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Link: https://lore.kernel.org/r/20250517165713.935384-1-xin@zytor.com
2025-05-15x86/cpuid: Set <asm/cpuid/api.h> as the main CPUID headerAhmed S. Darwish
The main CPUID header <asm/cpuid.h> was originally a storefront for the headers: <asm/cpuid/api.h> <asm/cpuid/leaf_0x2_api.h> Now that the latter CPUID(0x2) header has been merged into the former, there is no practical difference between <asm/cpuid.h> and <asm/cpuid/api.h>. Migrate all users to the <asm/cpuid/api.h> header, in preparation of the removal of <asm/cpuid.h>. Don't remove <asm/cpuid.h> just yet, in case some new code in -next started using it. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: x86-cpuid@lists.linux.dev Link: https://lore.kernel.org/r/20250508150240.172915-3-darwi@linutronix.de
2025-05-02x86/msr: Change the function type of native_read_msr_safe()Xin Li (Intel)
Modify the function type of native_read_msr_safe() to: int native_read_msr_safe(u32 msr, u64 *val) This change makes the function return an error code instead of the MSR value, aligning it with the type of native_write_msr_safe(). Consequently, their callers can check the results in the same way. While at it, convert leftover MSR data type "unsigned int" to u32. Signed-off-by: Xin Li (Intel) <xin@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Uros Bizjak <ubizjak@gmail.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Link: https://lore.kernel.org/r/20250427092027.1598740-16-xin@zytor.com
2025-05-02x86/pvops/msr: Refactor pv_cpu_ops.write_msr{,_safe}()Xin Li (Intel)
An MSR value is represented as a 64-bit unsigned integer, with existing MSR instructions storing it in EDX:EAX as two 32-bit segments. The new immediate form MSR instructions, however, utilize a 64-bit general-purpose register to store the MSR value. To unify the usage of all MSR instructions, let the default MSR access APIs accept an MSR value as a single 64-bit argument instead of two 32-bit segments. The dual 32-bit APIs are still available as convenient wrappers over the APIs that handle an MSR value as a single 64-bit argument. The following illustrates the updated derivation of the MSR write APIs: __wrmsrq(u32 msr, u64 val) / \ / \ native_wrmsrq(msr, val) native_wrmsr(msr, low, high) | | native_write_msr(msr, val) / \ / \ wrmsrq(msr, val) wrmsr(msr, low, high) When CONFIG_PARAVIRT is enabled, wrmsrq() and wrmsr() are defined on top of paravirt_write_msr(): paravirt_write_msr(u32 msr, u64 val) / \ / \ wrmsrq(msr, val) wrmsr(msr, low, high) paravirt_write_msr() invokes cpu.write_msr(msr, val), an indirect layer of pv_ops MSR write call: If on native: cpu.write_msr = native_write_msr If on Xen: cpu.write_msr = xen_write_msr Therefore, refactor pv_cpu_ops.write_msr{_safe}() to accept an MSR value in a single u64 argument, replacing the current dual u32 arguments. No functional change intended. Signed-off-by: Xin Li (Intel) <xin@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Uros Bizjak <ubizjak@gmail.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Link: https://lore.kernel.org/r/20250427092027.1598740-14-xin@zytor.com
2025-05-02x86/xen/msr: Remove the error pointer argument from set_seg()Xin Li (Intel)
set_seg() is used to write the following MSRs on Xen: MSR_FS_BASE MSR_KERNEL_GS_BASE MSR_GS_BASE But none of these MSRs are written using any MSR write safe API. Therefore there is no need to pass an error pointer argument to set_seg() for returning an error code to be used in MSR safe APIs. Remove the error pointer argument. Signed-off-by: Xin Li (Intel) <xin@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Uros Bizjak <ubizjak@gmail.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Link: https://lore.kernel.org/r/20250427092027.1598740-13-xin@zytor.com
2025-05-02x86/xen/msr: Remove pmu_msr_{read,write}()Xin Li (Intel)
As pmu_msr_{read,write}() are now wrappers of pmu_msr_chk_emulated(), remove them and use pmu_msr_chk_emulated() directly. As pmu_msr_chk_emulated() could easily return false in the cases where it would set *emul to false, remove the "emul" argument and use the return value instead. While at it, convert the data type of MSR index to u32 in functions called in pmu_msr_chk_emulated(). Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com> Suggested-by: Juergen Gross <jgross@suse.com> Signed-off-by: Xin Li (Intel) <xin@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Uros Bizjak <ubizjak@gmail.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Link: https://lore.kernel.org/r/20250427092027.1598740-12-xin@zytor.com
2025-05-02x86/xen/msr: Remove calling native_{read,write}_msr{,_safe}() in ↵Xin Li (Intel)
pmu_msr_{read,write}() hpa found that pmu_msr_write() is actually a completely pointless function: https://lore.kernel.org/lkml/0ec48b84-d158-47c6-b14c-3563fd14bcc4@zytor.com/ all it does is shuffle some arguments, then calls pmu_msr_chk_emulated() and if it returns true AND the emulated flag is clear then does *exactly the same thing* that the calling code would have done if pmu_msr_write() itself had returned true. And pmu_msr_read() does the equivalent stupidity. Remove the calls to native_{read,write}_msr{,_safe}() within pmu_msr_{read,write}(). Instead reuse the existing calling code that decides whether to call native_{read,write}_msr{,_safe}() based on the return value from pmu_msr_{read,write}(). Consequently, eliminate the need to pass an error pointer to pmu_msr_{read,write}(). While at it, refactor pmu_msr_write() to take the MSR value as a u64 argument, replacing the current dual u32 arguments, because the dual u32 arguments were only used to call native_write_msr{,_safe}(), which has now been removed. Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Xin Li (Intel) <xin@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Uros Bizjak <ubizjak@gmail.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Link: https://lore.kernel.org/r/20250427092027.1598740-11-xin@zytor.com
2025-05-02x86/msr: Add explicit includes of <asm/msr.h>Xin Li (Intel)
For historic reasons there are some TSC-related functions in the <asm/msr.h> header, even though there's an <asm/tsc.h> header. To facilitate the relocation of rdtsc{,_ordered}() from <asm/msr.h> to <asm/tsc.h> and to eventually eliminate the inclusion of <asm/msr.h> in <asm/tsc.h>, add an explicit <asm/msr.h> dependency to the source files that reference definitions from <asm/msr.h>. [ mingo: Clarified the changelog. ] Signed-off-by: Xin Li (Intel) <xin@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Kees Cook <keescook@chromium.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Uros Bizjak <ubizjak@gmail.com> Link: https://lore.kernel.org/r/20250501054241.1245648-1-xin@zytor.com
2025-04-01Merge tag 'mm-stable-2025-03-30-16-52' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - The series "Enable strict percpu address space checks" from Uros Bizjak uses x86 named address space qualifiers to provide compile-time checking of percpu area accesses. This has caused a small amount of fallout - two or three issues were reported. In all cases the calling code was found to be incorrect. - The series "Some cleanup for memcg" from Chen Ridong implements some relatively monir cleanups for the memcontrol code. - The series "mm: fixes for device-exclusive entries (hmm)" from David Hildenbrand fixes a boatload of issues which David found then using device-exclusive PTE entries when THP is enabled. More work is needed, but this makes thins better - our own HMM selftests now succeed. - The series "mm: zswap: remove z3fold and zbud" from Yosry Ahmed remove the z3fold and zbud implementations. They have been deprecated for half a year and nobody has complained. - The series "mm: further simplify VMA merge operation" from Lorenzo Stoakes implements numerous simplifications in this area. No runtime effects are anticipated. - The series "mm/madvise: remove redundant mmap_lock operations from process_madvise()" from SeongJae Park rationalizes the locking in the madvise() implementation. Performance gains of 20-25% were observed in one MADV_DONTNEED microbenchmark. - The series "Tiny cleanup and improvements about SWAP code" from Baoquan He contains a number of touchups to issues which Baoquan noticed when working on the swap code. - The series "mm: kmemleak: Usability improvements" from Catalin Marinas implements a couple of improvements to the kmemleak user-visible output. - The series "mm/damon/paddr: fix large folios access and schemes handling" from Usama Arif provides a couple of fixes for DAMON's handling of large folios. - The series "mm/damon/core: fix wrong and/or useless damos_walk() behaviors" from SeongJae Park fixes a few issues with the accuracy of kdamond's walking of DAMON regions. - The series "expose mapping wrprotect, fix fb_defio use" from Lorenzo Stoakes changes the interaction between framebuffer deferred-io and core MM. No functional changes are anticipated - this is preparatory work for the future removal of page structure fields. - The series "mm/damon: add support for hugepage_size DAMOS filter" from Usama Arif adds a DAMOS filter which permits the filtering by huge page sizes. - The series "mm: permit guard regions for file-backed/shmem mappings" from Lorenzo Stoakes extends the guard region feature from its present "anon mappings only" state. The feature now covers shmem and file-backed mappings. - The series "mm: batched unmap lazyfree large folios during reclamation" from Barry Song cleans up and speeds up the unmapping for pte-mapped large folios. - The series "reimplement per-vma lock as a refcount" from Suren Baghdasaryan puts the vm_lock back into the vma. Our reasons for pulling it out were largely bogus and that change made the code more messy. This patchset provides small (0-10%) improvements on one microbenchmark. - The series "Docs/mm/damon: misc DAMOS filters documentation fixes and improves" from SeongJae Park does some maintenance work on the DAMON docs. - The series "hugetlb/CMA improvements for large systems" from Frank van der Linden addresses a pile of issues which have been observed when using CMA on large machines. - The series "mm/damon: introduce DAMOS filter type for unmapped pages" from SeongJae Park enables users of DMAON/DAMOS to filter my the page's mapped/unmapped status. - The series "zsmalloc/zram: there be preemption" from Sergey Senozhatsky teaches zram to run its compression and decompression operations preemptibly. - The series "selftests/mm: Some cleanups from trying to run them" from Brendan Jackman fixes a pile of unrelated issues which Brendan encountered while runnimg our selftests. - The series "fs/proc/task_mmu: add guard region bit to pagemap" from Lorenzo Stoakes permits userspace to use /proc/pid/pagemap to determine whether a particular page is a guard page. - The series "mm, swap: remove swap slot cache" from Kairui Song removes the swap slot cache from the allocation path - it simply wasn't being effective. - The series "mm: cleanups for device-exclusive entries (hmm)" from David Hildenbrand implements a number of unrelated cleanups in this code. - The series "mm: Rework generic PTDUMP configs" from Anshuman Khandual implements a number of preparatoty cleanups to the GENERIC_PTDUMP Kconfig logic. - The series "mm/damon: auto-tune aggregation interval" from SeongJae Park implements a feedback-driven automatic tuning feature for DAMON's aggregation interval tuning. - The series "Fix lazy mmu mode" from Ryan Roberts fixes some issues in powerpc, sparc and x86 lazy MMU implementations. Ryan did this in preparation for implementing lazy mmu mode for arm64 to optimize vmalloc. - The series "mm/page_alloc: Some clarifications for migratetype fallback" from Brendan Jackman reworks some commentary to make the code easier to follow. - The series "page_counter cleanup and size reduction" from Shakeel Butt cleans up the page_counter code and fixes a size increase which we accidentally added late last year. - The series "Add a command line option that enables control of how many threads should be used to allocate huge pages" from Thomas Prescher does that. It allows the careful operator to significantly reduce boot time by tuning the parallalization of huge page initialization. - The series "Fix calculations in trace_balance_dirty_pages() for cgwb" from Tang Yizhou fixes the tracing output from the dirty page balancing code. - The series "mm/damon: make allow filters after reject filters useful and intuitive" from SeongJae Park improves the handling of allow and reject filters. Behaviour is made more consistent and the documention is updated accordingly. - The series "Switch zswap to object read/write APIs" from Yosry Ahmed updates zswap to the new object read/write APIs and thus permits the removal of some legacy code from zpool and zsmalloc. - The series "Some trivial cleanups for shmem" from Baolin Wang does as it claims. - The series "fs/dax: Fix ZONE_DEVICE page reference counts" from Alistair Popple regularizes the weird ZONE_DEVICE page refcount handling in DAX, permittig the removal of a number of special-case checks. - The series "refactor mremap and fix bug" from Lorenzo Stoakes is a preparatoty refactoring and cleanup of the mremap() code. - The series "mm: MM owner tracking for large folios (!hugetlb) + CONFIG_NO_PAGE_MAPCOUNT" from David Hildenbrand reworks the manner in which we determine whether a large folio is known to be mapped exclusively into a single MM. - The series "mm/damon: add sysfs dirs for managing DAMOS filters based on handling layers" from SeongJae Park adds a couple of new sysfs directories to ease the management of DAMON/DAMOS filters. - The series "arch, mm: reduce code duplication in mem_init()" from Mike Rapoport consolidates many per-arch implementations of mem_init() into code generic code, where that is practical. - The series "mm/damon/sysfs: commit parameters online via damon_call()" from SeongJae Park continues the cleaning up of sysfs access to DAMON internal data. - The series "mm: page_ext: Introduce new iteration API" from Luiz Capitulino reworks the page_ext initialization to fix a boot-time crash which was observed with an unusual combination of compile and cmdline options. - The series "Buddy allocator like (or non-uniform) folio split" from Zi Yan reworks the code to split a folio into smaller folios. The main benefit is lessened memory consumption: fewer post-split folios are generated. - The series "Minimize xa_node allocation during xarry split" from Zi Yan reduces the number of xarray xa_nodes which are generated during an xarray split. - The series "drivers/base/memory: Two cleanups" from Gavin Shan performs some maintenance work on the drivers/base/memory code. - The series "Add tracepoints for lowmem reserves, watermarks and totalreserve_pages" from Martin Liu adds some more tracepoints to the page allocator code. - The series "mm/madvise: cleanup requests validations and classifications" from SeongJae Park cleans up some warts which SeongJae observed during his earlier madvise work. - The series "mm/hwpoison: Fix regressions in memory failure handling" from Shuai Xue addresses two quite serious regressions which Shuai has observed in the memory-failure implementation. - The series "mm: reliable huge page allocator" from Johannes Weiner makes huge page allocations cheaper and more reliable by reducing fragmentation. - The series "Minor memcg cleanups & prep for memdescs" from Matthew Wilcox is preparatory work for the future implementation of memdescs. - The series "track memory used by balloon drivers" from Nico Pache introduces a way to track memory used by our various balloon drivers. - The series "mm/damon: introduce DAMOS filter type for active pages" from Nhat Pham permits users to filter for active/inactive pages, separately for file and anon pages. - The series "Adding Proactive Memory Reclaim Statistics" from Hao Jia separates the proactive reclaim statistics from the direct reclaim statistics. - The series "mm/vmscan: don't try to reclaim hwpoison folio" from Jinjiang Tu fixes our handling of hwpoisoned pages within the reclaim code. * tag 'mm-stable-2025-03-30-16-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (431 commits) mm/page_alloc: remove unnecessary __maybe_unused in order_to_pindex() x86/mm: restore early initialization of high_memory for 32-bits mm/vmscan: don't try to reclaim hwpoison folio mm/hwpoison: introduce folio_contain_hwpoisoned_page() helper cgroup: docs: add pswpin and pswpout items in cgroup v2 doc mm: vmscan: split proactive reclaim statistics from direct reclaim statistics selftests/mm: speed up split_huge_page_test selftests/mm: uffd-unit-tests support for hugepages > 2M docs/mm/damon/design: document active DAMOS filter type mm/damon: implement a new DAMOS filter type for active pages fs/dax: don't disassociate zero page entries MM documentation: add "Unaccepted" meminfo entry selftests/mm: add commentary about 9pfs bugs fork: use __vmalloc_node() for stack allocation docs/mm: Physical Memory: Populate the "Zones" section xen: balloon: update the NR_BALLOON_PAGES state hv_balloon: update the NR_BALLOON_PAGES state balloon_compaction: update the NR_BALLOON_PAGES state meminfo: add a per node counter for balloon drivers mm: remove references to folio in __memcg_kmem_uncharge_page() ...
2025-03-19x86/xen: Move Xen upcall handlerBrian Gerst
Move the upcall handler to Xen-specific files. No functional changes. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Reviewed-by: Sohil Mehta <sohil.mehta@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/20250314151220.862768-2-brgerst@gmail.com
2025-03-17Revert "x86/xen: allow nesting of same lazy mode"Ryan Roberts
Commit 49147beb0ccb ("x86/xen: allow nesting of same lazy mode") was added as a solution for a core-mm code change where arch_[enter|leave]_lazy_mmu_mode() started to be called in a nested manner; see commit bcc6cc832573 ("mm: add default definition of set_ptes()"). However, now that we have fixed the API to avoid nesting, we no longer need this capability in the x86 implementation. Additionally, from code review, I don't believe the fix was ever robust in the case of preemption occurring while in the nested lazy mode. The implementation usually deals with preemption by calling arch_leave_lazy_mmu_mode() from xen_start_context_switch() for the outgoing task if we are in the lazy mmu mode. Then in xen_end_context_switch(), it restarts the lazy mode by calling arch_enter_lazy_mmu_mode() for an incoming task that was in the lazy mode when it was switched out. But arch_leave_lazy_mmu_mode() will only unwind a single level of nesting. If we are in the double nest, then it's not fully unwound and per-cpu variables are left in a bad state. So the correct solution is to remove the possibility of nesting from the higher level (which has now been done) and remove this x86-specific solution. Link: https://lkml.kernel.org/r/20250303141542.3371656-6-ryan.roberts@arm.com Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Juergen Gross <jgross@suse.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Borislav Betkov <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juegren Gross <jgross@suse.com> Cc: Matthew Wilcow (Oracle) <willy@infradead.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-21Merge tag 'x86_misc_for_v6.14_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 updates from Borislav Petkov: - The first part of a restructuring of AMD's representation of a northbridge which is legacy now, and the creation of the new AMD node concept which represents the Zen architecture of having a collection of I/O devices within an SoC. Those nodes comprise the so-called data fabric on Zen. This has at least one practical advantage of not having to add a PCI ID each time a new data fabric PCI device releases. Eventually, the lot more uniform provider of data fabric functionality amd_node.c will be used by all the drivers which need it - Smaller cleanups * tag 'x86_misc_for_v6.14_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/amd_node: Use defines for SMN register offsets x86/amd_node: Remove dependency on AMD_NB x86/amd_node: Update __amd_smn_rw() error paths x86/amd_nb: Move SMN access code to a new amd_node driver x86/amd_nb, hwmon: (k10temp): Simplify amd_pci_dev_to_node_id() x86/amd_nb: Simplify function 3 search x86/amd_nb: Use topology info to get AMD node count x86/amd_nb: Simplify root device search x86/amd_nb: Simplify function 4 search x86: Start moving AMD node functionality out of AMD_NB x86/amd_nb: Clean up early_is_amd_nb() x86/amd_nb: Restrict init function to AMD-based systems x86/mtrr: Rename mtrr_overwrite_state() to guest_force_mtrr_state()
2025-01-21Merge tag 'x86_cpu_for_v6.14_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpuid updates from Borislav Petkov: - Remove the less generic CPU matching infra around struct x86_cpu_desc and use the generic struct x86_cpu_id thing - Remove magic naked numbers for CPUID functions and use proper defines of the prefix CPUID_LEAF_*. Consolidate some of the crazy use around the tree - Smaller cleanups and improvements * tag 'x86_cpu_for_v6.14_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Make all all CPUID leaf names consistent x86/fpu: Remove unnecessary CPUID level check x86/fpu: Move CPUID leaf definitions to common code x86/tsc: Remove CPUID "frequency" leaf magic numbers. x86/tsc: Move away from TSC leaf magic numbers x86/cpu: Move TSC CPUID leaf definition x86/cpu: Refresh DCA leaf reading code x86/cpu: Remove unnecessary MwAIT leaf checks x86/cpu: Use MWAIT leaf definition x86/cpu: Move MWAIT leaf definition to common header x86/cpu: Remove 'x86_cpu_desc' infrastructure x86/cpu: Move AMD erratum 1386 table over to 'x86_cpu_id' x86/cpu: Replace PEBS use of 'x86_cpu_desc' use with 'x86_cpu_id' x86/cpu: Expose only stepping min/max interface x86/cpu: Introduce new microcode matching helper x86/cpufeature: Document cpu_feature_enabled() as the default to use x86/paravirt: Remove the WBINVD callback x86/cpufeatures: Free up unused feature bits
2024-12-18x86/cpu: Make all all CPUID leaf names consistentDave Hansen
The leaf names are not consistent. Give them all a CPUID_LEAF_ prefix for consistency and vertical alignment. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Dave Jiang <dave.jiang@intel.com> # for ioatdma bits Link: https://lore.kernel.org/all/20241213205040.7B0C3241%40davehans-spike.ostc.intel.com
2024-12-18x86/cpu: Move MWAIT leaf definition to common headerDave Hansen
Begin constructing a common place to keep all CPUID leaf definitions. Move CPUID_MWAIT_LEAF to the CPUID header and include it where needed. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Zhao Liu <zhao1.liu@intel.com> Link: https://lore.kernel.org/all/20241213205028.EE94D02A%40davehans-spike.ostc.intel.com
2024-12-17x86/xen: add central hypercall functionsJuergen Gross
Add generic hypercall functions usable for all normal (i.e. not iret) hypercalls. Depending on the guest type and the processor vendor different functions need to be used due to the to be used instruction for entering the hypervisor: - PV guests need to use syscall - HVM/PVH guests on Intel need to use vmcall - HVM/PVH guests on AMD and Hygon need to use vmmcall As PVH guests need to issue hypercalls very early during boot, there is a 4th hypercall function needed for HVM/PVH which can be used on Intel and AMD processors. It will check the vendor type and then set the Intel or AMD specific function to use via static_call(). This is part of XSA-466 / CVE-2024-53241. Reported-by: Andrew Cooper <andrew.cooper3@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com> Co-developed-by: Peter Zijlstra <peterz@infradead.org>
2024-12-06x86/paravirt: Remove the WBINVD callbackJuergen Gross
The pv_ops::cpu.wbinvd paravirt callback is a leftover of lguest times. Today it is no longer needed, as all users use the native WBINVD implementation. Remove the callback and rename native_wbinvd() to wbinvd(). Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20241203071550.26487-1-jgross@suse.com
2024-12-04x86/mtrr: Rename mtrr_overwrite_state() to guest_force_mtrr_state()Kirill A. Shutemov
Rename the helper to better reflect its function. Suggested-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Link: https://lore.kernel.org/all/20241202073139.448208-1-kirill.shutemov%40linux.intel.com
2024-10-08x86/xen: mark boot CPU of PV guest in MSR_IA32_APICBASEJuergen Gross
Recent topology checks of the x86 boot code uncovered the need for PV guests to have the boot cpu marked in the APICBASE MSR. Fixes: 9d22c96316ac ("x86/topology: Handle bogus ACPI tables correctly") Reported-by: Niels Dettenbach <nd@syndicat.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Juergen Gross <jgross@suse.com>
2024-07-11x86/xen: eliminate some private header filesJuergen Gross
Under arch/x86/xen there is one large private header file xen-ops.h containing most of the Xen-private x86 related declarations, and then there are several small headers with a handful of declarations each. Merge the small headers into xen-ops.h. While doing that, move the declaration of xen_fifo_events from xen-ops.h into include/xen/events.h where it should have been from the beginning. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Message-ID: <20240710093718.14552-3-jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2024-05-02x86/xen: return a sane initial apic id when running as PV guestJuergen Gross
With recent sanity checks for topology information added, there are now warnings issued for APs when running as a Xen PV guest: [Firmware Bug]: CPU 1: APIC ID mismatch. CPUID: 0x0000 APIC: 0x0001 This is due to the initial APIC ID obtained via CPUID for PV guests is always 0. Avoid the warnings by synthesizing the CPUID data to contain the same initial APIC ID as xen_pv_smp_config() is using for registering the APIC IDs of all CPUs. Fixes: 52128a7a21f7 ("86/cpu/topology: Make the APIC mismatch warnings complete") Signed-off-by: Juergen Gross <jgross@suse.com>
2024-02-15x86/xen/smp_pv: Count number of vCPUs earlyThomas Gleixner
XEN/PV has a completely broken vCPU enumeration scheme, which just works by chance and provides zero topology information. Each vCPU ends up being a single core package. Dom0 provides MADT which can be used for topology information, but that table is the unmodified host table, which means that there can be more CPUs registered than the number of vCPUs XEN provides for the dom0 guest. DomU does not have ACPI and both rely on counting the possible vCPUs via an hypercall. To prepare for using CPUID topology information either via MADT or via fake APIC IDs count the number of possible CPUs during early boot and adjust nr_cpu_ids() accordingly. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240213210252.571795063@linutronix.de
2023-12-07x86/entry: Convert INT 0x80 emulation to IDTENTRYThomas Gleixner
There is no real reason to have a separate ASM entry point implementation for the legacy INT 0x80 syscall emulation on 64-bit. IDTENTRY provides all the functionality needed with the only difference that it does not: - save the syscall number (AX) into pt_regs::orig_ax - set pt_regs::ax to -ENOSYS Both can be done safely in the C code of an IDTENTRY before invoking any of the syscall related functions which depend on this convention. Aside of ASM code reduction this prepares for detecting and handling a local APIC injected vector 0x80. [ kirill.shutemov: More verbose comments ] Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@vger.kernel.org> # v6.0+
2023-09-19x86/xen: allow nesting of same lazy modeJuergen Gross
When running as a paravirtualized guest under Xen, Linux is using "lazy mode" for issuing hypercalls which don't need to take immediate effect in order to improve performance (examples are e.g. multiple PTE changes). There are two different lazy modes defined: MMU and CPU lazy mode. Today it is not possible to nest multiple lazy mode sections, even if they are of the same kind. A recent change in memory management added nesting of MMU lazy mode sections, resulting in a regression when running as Xen PV guest. Technically there is no reason why nesting of multiple sections of the same kind of lazy mode shouldn't be allowed. So add support for that for fixing the regression. Fixes: bcc6cc832573 ("mm: add default definition of set_ptes()") Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20230913113828.18421-4-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-09-19x86/xen: move paravirt lazy codeJuergen Gross
Only Xen is using the paravirt lazy mode code, so it can be moved to Xen specific sources. This allows to make some of the functions static or to merge them into their only call sites. While at it do a rename from "paravirt" to "xen" for all moved specifiers. No functional change. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20230913113828.18421-3-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-08-31Merge tag 'x86_shstk_for_6.6-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 shadow stack support from Dave Hansen: "This is the long awaited x86 shadow stack support, part of Intel's Control-flow Enforcement Technology (CET). CET consists of two related security features: shadow stacks and indirect branch tracking. This series implements just the shadow stack part of this feature, and just for userspace. The main use case for shadow stack is providing protection against return oriented programming attacks. It works by maintaining a secondary (shadow) stack using a special memory type that has protections against modification. When executing a CALL instruction, the processor pushes the return address to both the normal stack and to the special permission shadow stack. Upon RET, the processor pops the shadow stack copy and compares it to the normal stack copy. For more information, refer to the links below for the earlier versions of this patch set" Link: https://lore.kernel.org/lkml/20220130211838.8382-1-rick.p.edgecombe@intel.com/ Link: https://lore.kernel.org/lkml/20230613001108.3040476-1-rick.p.edgecombe@intel.com/ * tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits) x86/shstk: Change order of __user in type x86/ibt: Convert IBT selftest to asm x86/shstk: Don't retry vm_munmap() on -EINTR x86/kbuild: Fix Documentation/ reference x86/shstk: Move arch detail comment out of core mm x86/shstk: Add ARCH_SHSTK_STATUS x86/shstk: Add ARCH_SHSTK_UNLOCK x86: Add PTRACE interface for shadow stack selftests/x86: Add shadow stack test x86/cpufeatures: Enable CET CR4 bit for shadow stack x86/shstk: Wire in shadow stack interface x86: Expose thread features in /proc/$PID/status x86/shstk: Support WRSS for userspace x86/shstk: Introduce map_shadow_stack syscall x86/shstk: Check that signal frame is shadow stack mem x86/shstk: Check that SSP is aligned on sigreturn x86/shstk: Handle signals for shadow stack x86/shstk: Introduce routines modifying shstk x86/shstk: Handle thread shadow stack x86/shstk: Add user-mode shadow stack support ...
2023-08-30Merge tag 'x86_apic_for_6.6-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic updates from Dave Hansen: "This includes a very thorough rework of the 'struct apic' handlers. Quite a variety of them popped up over the years, especially in the 32-bit days when odd apics were much more in vogue. The end result speaks for itself, which is a removal of a ton of code and static calls to replace indirect calls. If there's any breakage here, it's likely to be around the 32-bit museum pieces that get light to no testing these days. Summary: - Rework apic callbacks, getting rid of unnecessary ones and coalescing lots of silly duplicates. - Use static_calls() instead of indirect calls for apic->foo() - Tons of cleanups an crap removal along the way" * tag 'x86_apic_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits) x86/apic: Turn on static calls x86/apic: Provide static call infrastructure for APIC callbacks x86/apic: Wrap IPI calls into helper functions x86/apic: Mark all hotpath APIC callback wrappers __always_inline x86/xen/apic: Mark apic __ro_after_init x86/apic: Convert other overrides to apic_update_callback() x86/apic: Replace acpi_wake_cpu_handler_update() and apic_set_eoi_cb() x86/apic: Provide apic_update_callback() x86/xen/apic: Use standard apic driver mechanism for Xen PV x86/apic: Provide common init infrastructure x86/apic: Wrap apic->native_eoi() into a helper x86/apic: Nuke ack_APIC_irq() x86/apic: Remove pointless arguments from [native_]eoi_write() x86/apic/noop: Tidy up the code x86/apic: Remove pointless NULL initializations x86/apic: Sanitize APIC ID range validation x86/apic: Prepare x2APIC for using apic::max_apic_id x86/apic: Simplify X2APIC ID validation x86/apic: Add max_apic_id member x86/apic: Wrap APIC ID validation into an inline ...
2023-08-28Merge tag 'acpi-6.6-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "These include new ACPICA material, a rework of the ACPI thermal driver, a switch-over of the ACPI processor driver to using _OSC instead of (long deprecated) _PDC for CPU initialization, a rework of firmware notifications handling in several drivers, fixes and cleanups for suspend-to-idle handling on AMD systems, ACPI backlight driver updates and more. Specifics: - Update the ACPICA code in the kernel to upstream revision 20230628 including the following changes: - Suppress a GCC 12 dangling-pointer warning (Philip Prindeville) - Reformat the ACPI_STATE_COMMON macro and its users (George Guo) - Replace the ternary operator with ACPI_MIN() (Jiangshan Yi) - Add support for _DSC as per ACPI 6.5 (Saket Dumbre) - Remove a duplicate macro from zephyr header (Najumon B.A) - Add data structures for GED and _EVT tracking (Jose Marinho) - Fix misspelled CDAT DSMAS define (Dave Jiang) - Simplify an error message in acpi_ds_result_push() (Christophe Jaillet) - Add a struct size macro related to SRAT (Dave Jiang) - Add AML_NO_OPERAND_RESOLVE flag to Timer (Abhishek Mainkar) - Add support for RISC-V external interrupt controllers in MADT (Sunil V L) - Add RHCT flags, CMO and MMU nodes (Sunil V L) - Change ACPICA version to 20230628 (Bob Moore) - Introduce new wrappers for ACPICA notify handler install/remove and convert multiple drivers to using their own Notify() handlers instead of the ACPI bus type .notify() slated for removal (Michal Wilczynski) - Add backlight=native DMI quirk for Apple iMac12,1 and iMac12,2 (Hans de Goede) - Put ACPI video and its child devices explicitly into D0 on boot to avoid platform firmware confusion (Kai-Heng Feng) - Add backlight=native DMI quirk for Lenovo Ideapad Z470 (Jiri Slaby) - Support obtaining physical CPU ID from MADT on LoongArch (Bibo Mao) - Convert ACPI CPU initialization to using _OSC instead of _PDC that has been depreceted since 2018 and dropped from the specification in ACPI 6.5 (Michal Wilczynski, Rafael Wysocki) - Drop non-functional nocrt parameter from ACPI thermal (Mario Limonciello) - Clean up the ACPI thermal driver, rework the handling of firmware notifications in it and make it provide a table of generic trip point structures to the core during initialization (Rafael Wysocki) - Defer enumeration of devices with _DEP pointing to IVSC (Wentong Wu) - Install SystemCMOS address space handler for ACPI000E (TAD) to meet platform firmware expectations on some platforms (Zhang Rui) - Fix finding the generic error data in the ACPi extlog driver for compatibility with old and new firmware interface versions (Xiaochun Lee) - Remove assorted unused declarations of functions (Yue Haibing) - Move AMBA bus scan handling into arm64 specific directory (Sudeep Holla) - Fix and clean up suspend-to-idle interface for AMD systems (Mario Limonciello, Andy Shevchenko) - Fix string truncation warning in pnpacpi_add_device() (Sunil V L)" * tag 'acpi-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (66 commits) ACPI: x86: s2idle: Add a function to get LPS0 constraint for a device ACPI: x86: s2idle: Add for_each_lpi_constraint() helper ACPI: x86: s2idle: Add more debugging for AMD constraints parsing ACPI: x86: s2idle: Fix a logic error parsing AMD constraints table ACPI: x86: s2idle: Catch multiple ACPI_TYPE_PACKAGE objects ACPI: x86: s2idle: Post-increment variables when getting constraints ACPI: Adjust #ifdef for *_lps0_dev use ACPI: TAD: Install SystemCMOS address space handler for ACPI000E ACPI: Remove assorted unused declarations of functions ACPI: extlog: Fix finding the generic error data for v3 structure PNP: ACPI: Fix string truncation warning ACPI: Remove unused extern declaration acpi_paddr_to_node() ACPI: video: Add backlight=native DMI quirk for Apple iMac12,1 and iMac12,2 ACPI: video: Put ACPI video and its child devices into D0 on boot ACPI: processor: LoongArch: Get physical ID from MADT ACPI: scan: Defer enumeration of devices with a _DEP pointing to IVSC device ACPI: thermal: Eliminate code duplication from acpi_thermal_notify() ACPI: thermal: Drop unnecessary thermal zone callbacks ACPI: thermal: Rework thermal_get_trend() ACPI: thermal: Use trip point table to register thermal zones ...
2023-08-21x86/xen: Make virt_to_pfn() a static inlineLinus Walleij
Making virt_to_pfn() a static inline taking a strongly typed (const void *) makes the contract of a passing a pointer of that type to the function explicit and exposes any misuse of the macro virt_to_pfn() acting polymorphic and accepting many types such as (void *), (unitptr_t) or (unsigned long) as arguments without warnings. Also fix all offending call sites to pass a (void *) rather than an unsigned long. Since virt_to_mfn() is wrapping virt_to_pfn() this function has become polymorphic as well so the usage need to be fixed up. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20230810-virt-to-phys-x86-xen-v1-1-9e966d333e7a@linaro.org Signed-off-by: Juergen Gross <jgross@suse.com>
2023-08-09x86/xen/apic: Use standard apic driver mechanism for Xen PVJuergen Gross
Instead of setting the Xen PV apic driver very early during boot, just use the standard apic driver probing by setting an appropriate x86_init.irqs.intr_mode_init callback. At the same time eliminate xen_apic_check() which has never been used. The #ifdef CONFIG_X86_LOCAL_APIC around the call of xen_init_apic() can be removed, too, as CONFIG_XEN depends on CONFIG_X86_LOCAL_APIC. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest) Link: https://lore.kernel.org/lkml/aa086365-fd02-210f-67c6-5c9175c0dfee@suse.com
2023-08-02x86/shstk: Add user control-protection fault handlerRick Edgecombe
A control-protection fault is triggered when a control-flow transfer attempt violates Shadow Stack or Indirect Branch Tracking constraints. For example, the return address for a RET instruction differs from the copy on the shadow stack. There already exists a control-protection fault handler for handling kernel IBT faults. Refactor this fault handler into separate user and kernel handlers, like the page fault handler. Add a control-protection handler for usermode. To avoid ifdeffery, put them both in a new file cet.c, which is compiled in the case of either of the two CET features supported in the kernel: kernel IBT or user mode shadow stack. Move some static inline functions from traps.c into a header so they can be used in cet.c. Opportunistically fix a comment in the kernel IBT part of the fault handler that is on the end of the line instead of preceding it. Keep the same behavior for the kernel side of the fault handler, except for converting a BUG to a WARN in the case of a #CP happening when the feature is missing. This unifies the behavior with the new shadow stack code, and also prevents the kernel from crashing under this situation which is potentially recoverable. The control-protection fault handler works in a similar way as the general protection fault handler. It provides the si_code SEGV_CPERR to the signal handler. Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org> Tested-by: Pengfei Xu <pengfei.xu@intel.com> Tested-by: John Allen <john.allen@amd.com> Tested-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/all/20230613001108.3040476-28-rick.p.edgecombe%40intel.com
2023-07-14ACPI: processor: Rename ACPI_PDC symbolsMichal Wilczynski
The prefix in the names of the ACPI_PDC symbols suggests that they are only relevant for _PDC, but in fact they can also be used in the _OSC. Change that prefix to a more generic ACPI_PROC_CAP that will better reflect the purpose of those symbols as they represent bits in a general processor capabilities buffer. Rename pdc_intel.h to proc_cap_intel.h to follow the change of the symbol name prefix. No intentional functional impact. Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com> [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-06-16x86/xen: Set default memory type for PV guests to WBJuergen Gross
When running as an unprivileged PV guest under Xen (not dom0), the default MTRR memory type should be write-back. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20230615123959.12298-1-jgross@suse.com
2023-06-01x86/xen: Set MTRR state when running as Xen PV initial domainJuergen Gross
When running as Xen PV initial domain (aka dom0), MTRRs are disabled by the hypervisor, but the system should nevertheless use correct cache memory types. This has always kind of worked, as disabled MTRRs resulted in disabled PAT, too, so that the kernel avoided code paths resulting in inconsistencies. This bypassed all of the sanity checks the kernel is doing with enabled MTRRs in order to avoid memory mappings with conflicting memory types. This has been changed recently, leading to PAT being accepted to be enabled, while MTRRs stayed disabled. The result is that mtrr_type_lookup() no longer is accepting all memory type requests, but started to return WB even if UC- was requested. This led to driver failures during initialization of some devices. In reality MTRRs are still in effect, but they are under complete control of the Xen hypervisor. It is possible, however, to retrieve the MTRR settings from the hypervisor. In order to fix those problems, overwrite the MTRR state via mtrr_overwrite_state() with the MTRR data from the hypervisor, if the system is running as a Xen dom0. Fixes: 72cbc8f04fe2 ("x86/PAT: Have pat_enabled() properly reflect state when running on Xen") Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20230502120931.20719-6-jgross@suse.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2023-03-17Merge tag 'for-linus-6.3-rc3-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - cleanup for xen time handling - enable the VGA console in a Xen PVH dom0 - cleanup in the xenfs driver * tag 'for-linus-6.3-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: remove unnecessary (void*) conversions x86/PVH: obtain VGA console info in Dom0 x86/xen/time: cleanup xen_tsc_safe_clocksource xen: update arch/x86/include/asm/xen/cpuid.h
2023-03-14x86/PVH: obtain VGA console info in Dom0Jan Beulich
A new platform-op was added to Xen to allow obtaining the same VGA console information PV Dom0 is handed. Invoke the new function and have the output data processed by xen_init_vga(). Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/8f315e92-7bda-c124-71cc-478ab9c5e610@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-02-21Merge tag 'x86_cpu_for_v6.3_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpuid updates from Borislav Petkov: - Cache the AMD debug registers in per-CPU variables to avoid MSR writes where possible, when supporting a debug registers swap feature for SEV-ES guests - Add support for AMD's version of eIBRS called Automatic IBRS which is a set-and-forget control of indirect branch restriction speculation resources on privilege change - Add support for a new x86 instruction - LKGS - Load kernel GS which is part of the FRED infrastructure - Reset SPEC_CTRL upon init to accomodate use cases like kexec which rediscover - Other smaller fixes and cleanups * tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/amd: Cache debug register values in percpu variables KVM: x86: Propagate the AMD Automatic IBRS feature to the guest x86/cpu: Support AMD Automatic IBRS x86/cpu, kvm: Add the SMM_CTL MSR not present feature x86/cpu, kvm: Add the Null Selector Clears Base feature x86/cpu, kvm: Move X86_FEATURE_LFENCE_RDTSC to its native leaf x86/cpu, kvm: Add the NO_NESTED_DATA_BP feature KVM: x86: Move open-coded CPUID leaf 0x80000021 EAX bit propagation code x86/cpu, kvm: Add support for CPUID_80000021_EAX x86/gsseg: Add the new <asm/gsseg.h> header to <asm/asm-prototypes.h> x86/gsseg: Use the LKGS instruction if available for load_gs_index() x86/gsseg: Move load_gs_index() to its own new header file x86/gsseg: Make asm_load_gs_index() take an u16 x86/opcode: Add the LKGS instruction to x86-opcode-map x86/cpufeature: Add the CPU feature bit for LKGS x86/bugs: Reset speculation control settings on init x86/cpu: Remove redundant extern x86_read_arch_cap_msr()
2023-01-13cpuidle, xenpv: Make more PARAVIRT_XXL noinstr cleanPeter Zijlstra
objtool found a few cases where this code called out into instrumented code: vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() leaves .noinstr.text section vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() leaves .noinstr.text section vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to HYPERVISOR_sched_op.constprop.0() leaves .noinstr.text section Solve this by: - marking arch_safe_halt(), wbinvd(), native_wbinvd() and HYPERVISOR_sched_op() as __always_inline(). - Explicitly uninlining xen_safe_halt() and pv_native_wbinvd() [they were already uninlined by the compiler on use as function pointers] and annotating them as 'noinstr'. - Annotating pv_native_safe_halt() as 'noinstr'. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20230112195541.171918174@infradead.org
2023-01-13x86/gsseg: Use the LKGS instruction if available for load_gs_index()H. Peter Anvin (Intel)
The LKGS instruction atomically loads a segment descriptor into the %gs descriptor registers, *except* that %gs.base is unchanged, and the base is instead loaded into MSR_IA32_KERNEL_GS_BASE, which is exactly what we want this function to do. Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20230112072032.35626-6-xin3.li@intel.com Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org>
2022-12-14Merge tag 'x86_core_for_v6.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 core updates from Borislav Petkov: - Add the call depth tracking mitigation for Retbleed which has been long in the making. It is a lighterweight software-only fix for Skylake-based cores where enabling IBRS is a big hammer and causes a significant performance impact. What it basically does is, it aligns all kernel functions to 16 bytes boundary and adds a 16-byte padding before the function, objtool collects all functions' locations and when the mitigation gets applied, it patches a call accounting thunk which is used to track the call depth of the stack at any time. When that call depth reaches a magical, microarchitecture-specific value for the Return Stack Buffer, the code stuffs that RSB and avoids its underflow which could otherwise lead to the Intel variant of Retbleed. This software-only solution brings a lot of the lost performance back, as benchmarks suggest: https://lore.kernel.org/all/20220915111039.092790446@infradead.org/ That page above also contains a lot more detailed explanation of the whole mechanism - Implement a new control flow integrity scheme called FineIBT which is based on the software kCFI implementation and uses hardware IBT support where present to annotate and track indirect branches using a hash to validate them - Other misc fixes and cleanups * tag 'x86_core_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (80 commits) x86/paravirt: Use common macro for creating simple asm paravirt functions x86/paravirt: Remove clobber bitmask from .parainstructions x86/debug: Include percpu.h in debugreg.h to get DECLARE_PER_CPU() et al x86/cpufeatures: Move X86_FEATURE_CALL_DEPTH from bit 18 to bit 19 of word 11, to leave space for WIP X86_FEATURE_SGX_EDECCSSA bit x86/Kconfig: Enable kernel IBT by default x86,pm: Force out-of-line memcpy() objtool: Fix weak hole vs prefix symbol objtool: Optimize elf_dirty_reloc_sym() x86/cfi: Add boot time hash randomization x86/cfi: Boot time selection of CFI scheme x86/ibt: Implement FineIBT objtool: Add --cfi to generate the .cfi_sites section x86: Add prefix symbols for function padding objtool: Add option to generate prefix symbols objtool: Avoid O(bloody terrible) behaviour -- an ode to libelf objtool: Slice up elf_create_section_symbol() kallsyms: Revert "Take callthunks into account" x86: Unconfuse CONFIG_ and X86_FEATURE_ namespaces x86/retpoline: Fix crash printing warning x86/paravirt: Fix a !PARAVIRT build warning ...
2022-12-13Merge tag 'x86_boot_for_v6.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Borislav Petkov: "A of early boot cleanups and fixes. - Do some spring cleaning to the compressed boot code by moving the EFI mixed-mode code to a separate compilation unit, the AMD memory encryption early code where it belongs and fixing up build dependencies. Make the deprecated EFI handover protocol optional with the goal of removing it at some point (Ard Biesheuvel) - Skip realmode init code on Xen PV guests as it is not needed there - Remove an old 32-bit PIC code compiler workaround" * tag 'x86_boot_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Remove x86_32 PIC using %ebx workaround x86/boot: Skip realmode init code when running as Xen PV guest x86/efi: Make the deprecated EFI handover protocol optional x86/boot/compressed: Only build mem_encrypt.S if AMD_MEM_ENCRYPT=y x86/boot/compressed: Adhere to calling convention in get_sev_encryption_bit() x86/boot/compressed: Move startup32_check_sev_cbit() out of head_64.S x86/boot/compressed: Move startup32_check_sev_cbit() into .text x86/boot/compressed: Move startup32_load_idt() out of head_64.S x86/boot/compressed: Move startup32_load_idt() into .text section x86/boot/compressed: Pull global variable reference into startup32_load_idt() x86/boot/compressed: Avoid touching ECX in startup32_set_idt_entry() x86/boot/compressed: Simplify IDT/GDT preserve/restore in the EFI thunk x86/boot/compressed, efi: Merge multiple definitions of image_offset into one x86/boot/compressed: Move efi32_pe_entry() out of head_64.S x86/boot/compressed: Move efi32_entry out of head_64.S x86/boot/compressed: Move efi32_pe_entry into .text section x86/boot/compressed: Move bootargs parsing out of 32-bit startup code x86/boot/compressed: Move 32-bit entrypoint code into .text section x86/boot/compressed: Rename efi_thunk_64.S to efi-mixed.S
2022-12-12Merge tag 'random-6.2-rc1-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/crng/random Pull random number generator updates from Jason Donenfeld: - Replace prandom_u32_max() and various open-coded variants of it, there is now a new family of functions that uses fast rejection sampling to choose properly uniformly random numbers within an interval: get_random_u32_below(ceil) - [0, ceil) get_random_u32_above(floor) - (floor, U32_MAX] get_random_u32_inclusive(floor, ceil) - [floor, ceil] Coccinelle was used to convert all current users of prandom_u32_max(), as well as many open-coded patterns, resulting in improvements throughout the tree. I'll have a "late" 6.1-rc1 pull for you that removes the now unused prandom_u32_max() function, just in case any other trees add a new use case of it that needs to converted. According to linux-next, there may be two trivial cases of prandom_u32_max() reintroductions that are fixable with a 's/.../.../'. So I'll have for you a final conversion patch doing that alongside the removal patch during the second week. This is a treewide change that touches many files throughout. - More consistent use of get_random_canary(). - Updates to comments, documentation, tests, headers, and simplification in configuration. - The arch_get_random*_early() abstraction was only used by arm64 and wasn't entirely useful, so this has been replaced by code that works in all relevant contexts. - The kernel will use and manage random seeds in non-volatile EFI variables, refreshing a variable with a fresh seed when the RNG is initialized. The RNG GUID namespace is then hidden from efivarfs to prevent accidental leakage. These changes are split into random.c infrastructure code used in the EFI subsystem, in this pull request, and related support inside of EFISTUB, in Ard's EFI tree. These are co-dependent for full functionality, but the order of merging doesn't matter. - Part of the infrastructure added for the EFI support is also used for an improvement to the way vsprintf initializes its siphash key, replacing an sleep loop wart. - The hardware RNG framework now always calls its correct random.c input function, add_hwgenerator_randomness(), rather than sometimes going through helpers better suited for other cases. - The add_latent_entropy() function has long been called from the fork handler, but is a no-op when the latent entropy gcc plugin isn't used, which is fine for the purposes of latent entropy. But it was missing out on the cycle counter that was also being mixed in beside the latent entropy variable. So now, if the latent entropy gcc plugin isn't enabled, add_latent_entropy() will expand to a call to add_device_randomness(NULL, 0), which adds a cycle counter, without the absent latent entropy variable. - The RNG is now reseeded from a delayed worker, rather than on demand when used. Always running from a worker allows it to make use of the CPU RNG on platforms like S390x, whose instructions are too slow to do so from interrupts. It also has the effect of adding in new inputs more frequently with more regularity, amounting to a long term transcript of random values. Plus, it helps a bit with the upcoming vDSO implementation (which isn't yet ready for 6.2). - The jitter entropy algorithm now tries to execute on many different CPUs, round-robining, in hopes of hitting even more memory latencies and other unpredictable effects. It also will mix in a cycle counter when the entropy timer fires, in addition to being mixed in from the main loop, to account more explicitly for fluctuations in that timer firing. And the state it touches is now kept within the same cache line, so that it's assured that the different execution contexts will cause latencies. * tag 'random-6.2-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (23 commits) random: include <linux/once.h> in the right header random: align entropy_timer_state to cache line random: mix in cycle counter when jitter timer fires random: spread out jitter callback to different CPUs random: remove extraneous period and add a missing one in comments efi: random: refresh non-volatile random seed when RNG is initialized vsprintf: initialize siphash key using notifier random: add back async readiness notifier random: reseed in delayed work rather than on-demand random: always mix cycle counter in add_latent_entropy() hw_random: use add_hwgenerator_randomness() for early entropy random: modernize documentation comment on get_random_bytes() random: adjust comment to account for removed function random: remove early archrandom abstraction random: use random.trust_{bootloader,cpu} command line option only stackprotector: actually use get_random_canary() stackprotector: move get_random_canary() into stackprotector.h treewide: use get_random_u32_inclusive() when possible treewide: use get_random_u32_{above,below}() instead of manual loop treewide: use get_random_u32_below() instead of deprecated function ...
2022-11-25x86/boot: Skip realmode init code when running as Xen PV guestJuergen Gross
When running as a Xen PV guest there is no need for setting up the realmode trampoline, as realmode isn't supported in this environment. Trying to setup the trampoline has been proven to be problematic in some cases, especially when trying to debug early boot problems with Xen requiring to keep the EFI boot-services memory mapped (some firmware variants seem to claim basically all memory below 1Mb for boot services). Introduce new x86_platform_ops operations for that purpose, which can be set to a NOP by the Xen PV specific kernel boot code. [ bp: s/call_init_real_mode/do_init_real_mode/ ] Fixes: 084ee1c641a0 ("x86, realmode: Relocator for realmode code") Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20221123114523.3467-1-jgross@suse.com
2022-11-21Merge tag 'v6.1-rc6' into x86/core, to resolve conflictsIngo Molnar
Resolve conflicts between these commits in arch/x86/kernel/asm-offsets.c: # upstream: debc5a1ec0d1 ("KVM: x86: use a separate asm-offsets.c file") # retbleed work in x86/core: 5d8213864ade ("x86/retbleed: Add SKL return thunk") ... and these commits in include/linux/bpf.h: # upstram: 18acb7fac22f ("bpf: Revert ("Fix dispatcher patchable function entry to 5 bytes nop")") # x86/core commits: 931ab63664f0 ("x86/ibt: Implement FineIBT") bea75b33895f ("x86/Kconfig: Introduce function padding") The latter two modify BPF_DISPATCHER_ATTRIBUTES(), which was removed upstream. Conflicts: arch/x86/kernel/asm-offsets.c include/linux/bpf.h Signed-off-by: Ingo Molnar <mingo@kernel.org>
2022-11-18stackprotector: move get_random_canary() into stackprotector.hJason A. Donenfeld
This has nothing to do with random.c and everything to do with stack protectors. Yes, it uses randomness. But many things use randomness. random.h and random.c are concerned with the generation of randomness, not with each and every use. So move this function into the more specific stackprotector.h file where it belongs. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-11-16Merge tag 'for-linus-6.1-rc6-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: "Two trivial cleanups, and three simple fixes" * tag 'for-linus-6.1-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/platform-pci: use define instead of literal number xen/platform-pci: add missing free_irq() in error path xen-pciback: Allow setting PCI_MSIX_FLAGS_MASKALL too xen/pcpu: fix possible memory leak in register_pcpu() x86/xen: Use kstrtobool() instead of strtobool()
2022-11-14x86/xen: Use kstrtobool() instead of strtobool()Christophe JAILLET
strtobool() is the same as kstrtobool(). However, the latter is more used within the kernel. In order to remove strtobool() and slightly simplify kstrtox.h, switch to the other function name. While at it, include the corresponding header file (<linux/kstrtox.h>) Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/e91af3c8708af38b1c57e0a2d7eb9765dda0e963.1667336095.git.christophe.jaillet@wanadoo.fr Signed-off-by: Juergen Gross <jgross@suse.com>
2022-10-17x86/cpu: Get rid of redundant switch_to_new_gdt() invocationsThomas Gleixner
The only place where switch_to_new_gdt() is required is early boot to switch from the early GDT to the direct GDT. Any other invocation is completely redundant because it does not change anything. Secondary CPUs come out of the ASM code with GDT and GSBASE correctly set up. The same is true for XEN_PV. Remove all the voodoo invocations which are left overs from the ancient past, rename the function to switch_gdt_and_percpu_base() and mark it init. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220915111143.198076128@infradead.org
2022-10-12Merge tag 'for-linus-6.1-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - Some minor typo fixes - A fix of the Xen pcifront driver for supporting the device model to run in a Linux stub domain - A cleanup of the pcifront driver - A series to enable grant-based virtio with Xen on x86 - A cleanup of Xen PV guests to distinguish between safe and faulting MSR accesses - Two fixes of the Xen gntdev driver - Two fixes of the new xen grant DMA driver * tag 'for-linus-6.1-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: Kconfig: Fix spelling mistake "Maxmium" -> "Maximum" xen/pv: support selecting safe/unsafe msr accesses xen/pv: refactor msr access functions to support safe and unsafe accesses xen/pv: fix vendor checks for pmu emulation xen/pv: add fault recovery control to pmu msr accesses xen/virtio: enable grant based virtio on x86 xen/virtio: use dom0 as default backend for CONFIG_XEN_VIRTIO_FORCE_GRANT xen/virtio: restructure xen grant dma setup xen/pcifront: move xenstore config scanning into sub-function xen/gntdev: Accommodate VMA splitting xen/gntdev: Prevent leaking grants xen/virtio: Fix potential deadlock when accessing xen_grant_dma_devices xen/virtio: Fix n_pages calculation in xen_grant_dma_map(unmap)_page() xen/xenbus: Fix spelling mistake "hardward" -> "hardware" xen-pcifront: Handle missed Connected state
2022-10-11xen/pv: support selecting safe/unsafe msr accessesJuergen Gross
Instead of always doing the safe variants for reading and writing MSRs in Xen PV guests, make the behavior controllable via Kconfig option and a boot parameter. The default will be the current behavior, which is to always use the safe variant. Signed-off-by: Juergen Gross <jgross@suse.com>