[PATCH v4 0/5] x86/pkeys: update PKRU to enable pkey 0 before

From: Aruna Ramakrishna
Date: Tue May 28 2024 - 10:43:51 EST


v4 updates (based on review feedback from Thomas Gleixner):
- Simplified update_pkru_in_sigframe()
- Changed sigpkru to enable minimally required keys (init_pkru and current
pkru)
- Modified pkey_sighandler_tests.c to use kselfttest framework
- Fixed commit descriptions
- Fixed sigreturn use case (pointed out by Jeff Xu)
- Added a new sigreturn test case

v3 updates (based on review feedback from Ingo Molnar and Dave Hansen):
- Split the original patch into 3:
- function interface changes
- helper functions
- functional change to write pkru on sigframe
- Enabled all pkeys before XSAVE - i.e. wrpkru(0), rather than assuming
that the alt sig stack is always protected by pkey 0.
- Added a few test cases in pkey_sighandler_tests.c.

I had some trouble adding these tests to
tools/testing/selftests/mm/protection_keys.c, so they're in a separate
file.

Aruna Ramakrishna (4):
x86/pkeys: Add PKRU as a parameter in signal handling functions
x86/pkeys: Add helper functions to update PKRU on sigframe
x86/pkeys: Update PKRU to enable minimally required pkeys before XSAVE
x86/pkeys: Restore altstack before sigcontext

Keith Lucas (1):
selftests/mm: Add new testcases for pkeys

arch/x86/include/asm/fpu/signal.h | 2 +-
arch/x86/include/asm/sighandling.h | 10 +-
arch/x86/kernel/fpu/signal.c | 27 +-
arch/x86/kernel/fpu/xstate.c | 13 +
arch/x86/kernel/fpu/xstate.h | 1 +
arch/x86/kernel/signal.c | 42 +-
arch/x86/kernel/signal_32.c | 12 +-
arch/x86/kernel/signal_64.c | 14 +-
tools/testing/selftests/mm/Makefile | 5 +-
tools/testing/selftests/mm/pkey-helpers.h | 11 +-
.../selftests/mm/pkey_sighandler_tests.c | 480 ++++++++++++++++++
tools/testing/selftests/mm/protection_keys.c | 10 -
12 files changed, 582 insertions(+), 45 deletions(-)
create mode 100644 tools/testing/selftests/mm/pkey_sighandler_tests.c


base-commit: a38297e3fb012ddfa7ce0321a7e5a8daeb1872b6
prerequisite-patch-id: d84439301b44c03df2555d3722ec512001ae52f2
--
2.39.3