fix(vmm): Support kernel >= 5.16 and < 5.17 for xfeature enabling #5447
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Codecov Report❌ Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## main #5447 +/- ##
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- Coverage 82.76% 82.75% -0.02%
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Files 263 263
Lines 27300 27307 +7
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+ Hits 22594 22597 +3
- Misses 4706 4710 +4
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zulinx86
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Status: Awaiting review
Manciukic
previously approved these changes
Oct 1, 2025
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I think we should add a changelog entry. |
It is the kernel commit that actually is needed for ARCH_GET_XCOMP_SUPP. Signed-off-by: Takahiro Itazuri <[email protected]>
The link would be helpful for people who don't have much context around that. Signed-off-by: Takahiro Itazuri <[email protected]>
The Linux kernel introduced some arch_prctl() APIs (ARCH_GET_XCOMP_SUPP, ARCH_GET_XCOMP_PERM and ARCH_REQ_XCOMP_PERM) to support dynamic XSTATE feature enabling for "userspace applications" in 5.16 [1]. To support that for "KVM guest", v5.17 introduced additional arch_prctl() APIs (ARCH_GET_XCOMP_GUEST_PERM and ARCH_REQ_XCOMP_GUEST_PERM) [2]. Note that ARCH_XCOMP_GUEST_SUPP does not exist, so regardless of userspace application or KVM guest, ARCH_GET_XCOMP_SUPP is used to retrieve supported features. As a result, kernel versions >= 5.16 and < 5.17 report supported features via ARCH_GET_XCOMP_SUPP but ARCH_REQ_XCOMP_GUEST_PERM fail with EINVAL. [1]: torvalds/linux@db8268d [2]: torvalds/linux@980fe2f Signed-off-by: Takahiro Itazuri <[email protected]>
Manciukic
approved these changes
Oct 2, 2025
roypat
approved these changes
Oct 2, 2025
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Fixes #5438.
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