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Commit a5dbd76a authored by Linus Torvalds's avatar Linus Torvalds
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Merge tag 'x86-urgent-2024-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:

 - Prevent a deadlock on cpu_hotplug_lock in the aperf/mperf driver.

   A recent change in the ACPI code which consolidated code pathes moved
   the invocation of init_freq_invariance_cppc() to be moved to a CPU
   hotplug handler. The first invocation on AMD CPUs ends up enabling a
   static branch which dead locks because the static branch enable tries
   to acquire cpu_hotplug_lock but that lock is already held write by
   the hotplug machinery.

   Use static_branch_enable_cpuslocked() instead and take the hotplug
   lock read for the Intel code path which is invoked from the
   architecture code outside of the CPU hotplug operations.

 - Fix the number of reserved bits in the sev_config structure bit field
   so that the bitfield does not exceed 64 bit.

 - Add missing Zen5 model numbers

 - Fix the alignment assumptions of pti_clone_pgtable() and
   clone_entry_text() on 32-bit:

   The code assumes PMD aligned code sections, but on 32-bit the kernel
   entry text is not PMD aligned. So depending on the code size and
   location, which is configuration and compiler dependent, entry text
   can cross a PMD boundary. As the start is not PMD aligned adding PMD
   size to the start address is larger than the end address which
   results in partially mapped entry code for user space. That causes
   endless recursion on the first entry from userspace (usually #PF).

   Cure this by aligning the start address in the addition so it ends up
   at the next PMD start address.

   clone_entry_text() enforces PMD mapping, but on 32-bit the tail might
   eventually be PTE mapped, which causes a map fail because the PMD for
   the tail is not a large page mapping. Use PTI_LEVEL_KERNEL_IMAGE for
   the clone() invocation which resolves to PTE on 32-bit and PMD on
   64-bit.

 - Zero the 8-byte case for get_user() on range check failure on 32-bit

   The recend consolidation of the 8-byte get_user() case broke the
   zeroing in the failure case again. Establish it by clearing ECX
   before the range check and not afterwards as that obvioulsy can't be
   reached when the range check fails

* tag 'x86-urgent-2024-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/uaccess: Zero the 8-byte get_range case on failure on 32-bit
  x86/mm: Fix pti_clone_entry_text() for i386
  x86/mm: Fix pti_clone_pgtable() alignment assumption
  x86/setup: Parse the builtin command line before merging
  x86/CPU/AMD: Add models 0x60-0x6f to the Zen5 range
  x86/sev: Fix __reserved field in sev_config
  x86/aperfmperf: Fix deadlock on cpu_hotplug_lock
parents 61ca6c78 dd35a093
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