]> www.infradead.org Git - nvme.git/commit
Revert "KVM: arm64: nv: Fix RESx behaviour of disabled FGTs with negative polarity"
authorOliver Upton <oliver.upton@linux.dev>
Mon, 8 Jul 2024 19:50:51 +0000 (19:50 +0000)
committerOliver Upton <oliver.upton@linux.dev>
Mon, 8 Jul 2024 19:50:51 +0000 (19:50 +0000)
commitcb52b5c8b81bfbc34df13537d82cd1849725d6c7
treec401770b8c83025fa0129180d3a04363506ef6dc
parent3dc14eefa504d2fbe8e75113c7bb164a20bc39b0
Revert "KVM: arm64: nv: Fix RESx behaviour of disabled FGTs with negative polarity"

This reverts commit eb9d53d4a949c6d6d7c9f130e537f6b5687fedf9.

As Marc pointed out on the list [*], this patch is wrong, and those who
find themselves in the SOB chain should have their heads checked.

Annoyingly, the architecture has some FGT trap bits that are negative
(i.e. 0 implies trap), and there was some confusion how KVM handles
this for nested guests. However, it is clear now that KVM honors the
RES0-ness of FGT traps already, meaning traps for features never exposed
to the guest hypervisor get handled at L0. As they should.

Link: https://lore.kernel.org/kvmarm/86bk3c3uss.wl-maz@kernel.org/T/#mb9abb3dd79f6a4544a91cb35676bd637c3a5e836
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
arch/arm64/kvm/nested.c