mirror of https://github.com/torvalds/linux.git
8ba38a7a9a
emulate_vsyscall() expects to see X86_PF_INSTR in PFEC on a vsyscall page fault, but the CPU does not report X86_PF_INSTR if neither X86_FEATURE_NX nor X86_FEATURE_SMEP are enabled. X86_FEATURE_NX should be enabled on nearly all 64-bit CPUs, except for early P4 processors that did not support this feature. Instead of explicitly checking for X86_PF_INSTR, compare the fault address to RIP. On machines with X86_FEATURE_NX enabled, issue a warning if RIP is equal to fault address but X86_PF_INSTR is absent. [ dhansen: flesh out code comments ] Originally-by: Dave Hansen <dave.hansen@intel.com> Reported-by: Andrew Cooper <andrew.cooper3@citrix.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> Link: https://lore.kernel.org/all/bd81a98b-f8d4-4304-ac55-d4151a1a77ab@intel.com Link: https://lore.kernel.org/all/20250624145918.2720487-1-kirill.shutemov%40linux.intel.com |
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| Makefile | ||
| vsyscall_64.c | ||
| vsyscall_emu_64.S | ||
| vsyscall_trace.h | ||