The branch main has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=eb8326421e6b35b0dee1a8db669914a97bce5cdf
commit eb8326421e6b35b0dee1a8db669914a97bce5cdf Author: Konstantin Belousov <[email protected]> AuthorDate: 2024-10-03 03:51:20 +0000 Commit: Konstantin Belousov <[email protected]> CommitDate: 2024-10-03 06:19:09 +0000 iommu_qi_seq_processed: use atomic to read hw-written seq number otherwise iommu_qi_wait_for_seq() can be legitimately optimized out. Sponsored by: Advanced Micro Devices (AMD) Sponsored by: The FreeBSD Foundation MFC after: 1 week --- sys/x86/iommu/iommu_utils.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/sys/x86/iommu/iommu_utils.c b/sys/x86/iommu/iommu_utils.c index 8ff15cc86cb8..db8f94eb584f 100644 --- a/sys/x86/iommu/iommu_utils.c +++ b/sys/x86/iommu/iommu_utils.c @@ -350,8 +350,8 @@ iommu_qi_seq_processed(struct iommu_unit *unit, x86c = IOMMU2X86C(unit); gen = x86c->inv_waitd_gen; - return (pseq->gen < gen || - (pseq->gen == gen && pseq->seq <= x86c->inv_waitd_seq_hw)); + return (pseq->gen < gen || (pseq->gen == gen && pseq->seq <= + atomic_load_64(&x86c->inv_waitd_seq_hw))); } void
