Messages in this thread | | | From | Yu-cheng Yu <> | Subject | [PATCH 0/3] Fix two issues in XSAVES offset calculation | Date | Thu, 9 Jan 2020 13:14:49 -0800 |
| |
This series fixes two issues in XSAVES offset calculation:
- In setup_xstate_features(), supervisor xstate offsets are left as -1's, but still being tracked as last_good_offset; - In setup_xstate_comp(), alignments are being added to disabled xstate offsets.
These issues have not been visible because supervisor xstates have not been enabled and there is no xfeature requiring alignment. They are triggered only when adding an aligned non-supervisor xstate after CET [1] supervisor states.
To detect future potential issues, also add a patch to issue warnings when checking alignments of disabled xfeatures.
Details are in each patch's commit log.
[1] CET patches:
https://lkml.kernel.org/r/20190813205225.12032-1-yu-cheng.yu@intel.com/ https://lkml.kernel.org/r/20190813205359.12196-1-yu-cheng.yu@intel.com/
Yu-cheng Yu (3): x86/fpu/xstate: Fix last_good_offset in setup_xstate_features() x86/fpu/xstate: Fix XSAVES offsets in setup_xstate_comp() x86/fpu/xstate: WARN_ONCE on checking alignment of disabled xfeatures
arch/x86/kernel/fpu/xstate.c | 61 +++++++++++++++++++----------------- 1 file changed, 32 insertions(+), 29 deletions(-)
-- 2.21.0
| |