[PATCH v2 0/6] x86: Clean up fast syscall return validation

From: Brian Gerst
Date: Fri Jul 21 2023 - 12:10:52 EST


This patch set cleans up the tests done to determine if a fast syscall
return instruction can be used to return to userspace. It converts the
code to C, and refactors existing code to be more readable.

v2:
- Fix shift value for canonical RIP test and use
__is_canonical_address()

Brian Gerst (6):
x86/entry/64: Remove obsolete comment on tracing vs. SYSRET
x86/entry/64: Convert SYSRET validation tests to C
x86/entry/compat: Combine return value test from syscall handler
x86/entry/32: Convert do_fast_syscall_32() to bool return type
x86/entry/32: Remove SEP test for SYSEXIT
x86/entry/32: Clean up syscall fast exit tests

arch/x86/entry/common.c | 99 +++++++++++++++++++++-----------
arch/x86/entry/entry_32.S | 2 +-
arch/x86/entry/entry_64.S | 68 +---------------------
arch/x86/entry/entry_64_compat.S | 12 ++--
arch/x86/include/asm/syscall.h | 6 +-
5 files changed, 77 insertions(+), 110 deletions(-)

--
2.41.0