[PATCH v5 0/3] x86/bugs: more BHI

From: Josh Poimboeuf
Date: Tue May 07 2024 - 01:30:22 EST


Patch 1 fixes some objtool warnings and enables noreturn-related
optimizations for direct-called syscall handlers.

Patches 2 and 3 add 'spectre_bhi=vmexit' which is useful for mitigating
BHI in cloud host environments.

v5:
- dropped syscall hardening patch for now
- dropped "Fix CPU mitigation defaults for !x86" in favor of Sean's fix
- patch 1 fixes (Paul)

Josh Poimboeuf (3):
x86/syscall: Mark exit[_group] syscall handlers __noreturn
x86/bugs: Remove duplicate Spectre cmdline option descriptions
x86/bugs: Add 'spectre_bhi=vmexit' cmdline option

Documentation/admin-guide/hw-vuln/spectre.rst | 84 ++-----------------
.../admin-guide/kernel-parameters.txt | 12 ++-
arch/x86/entry/syscall_32.c | 10 ++-
arch/x86/entry/syscall_64.c | 9 +-
arch/x86/entry/syscall_x32.c | 7 +-
arch/x86/entry/syscalls/syscall_32.tbl | 6 +-
arch/x86/entry/syscalls/syscall_64.tbl | 6 +-
arch/x86/kernel/cpu/bugs.c | 16 ++--
arch/x86/um/sys_call_table_32.c | 10 ++-
arch/x86/um/sys_call_table_64.c | 11 ++-
scripts/syscalltbl.sh | 18 +++-
tools/objtool/noreturns.h | 4 +
12 files changed, 85 insertions(+), 108 deletions(-)

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2.44.0