>-----Original Message----- >From: Cao, Junjie <junjie.cao@intel.com> >Subject: [PATCH v4 0/2] intel_iommu: fix guest-triggerable assert in MMIO >handlers > >An 8-byte guest access to a 32-bit-only VT-d register hits >assert(size == 4) and aborts QEMU. Found by generic-fuzz. > >v1: https://lore.kernel.org/all/20260420170523.17908-1-junjie.cao@intel.com/ >v2: https://lore.kernel.org/all/20260424201842.176953-1-junjie.cao@intel.com/ >v3: https://lore.kernel.org/all/20260506031942.251335-1-junjie.cao@intel.com/ > >Changes in v4: > - Switch the guest-error log from error_report_once() to > qemu_log_mask(LOG_GUEST_ERROR, ...) so it is surfaced only > under -d guest_errors (Zhenzhong). > - Add a block comment at each of the 4 reachable sites > (FECTL 0x38, IECTL 0xa0, IEADDR 0xa8, PECTL 0xe0) > explaining why the check must stay, so future readers do > not delete it as "harmless" (Yi). > - No functional change beyond the logging-API swap. > >Changes in v3: > - Drop v2's min_access_size=8 approach: per Zhenzhong, it > silently zero-extends 4-byte guest writes, wiping upper > wmask bits of 64-bit registers and firing triggers gated > on size==8. > - Keep min_access_size=4. Remove the 25 assert(size == 4) > sites: 21 are unreachable (non-8-aligned), the 4 reachable > (FECTL 0x38, IECTL 0xa0, IEADDR 0xa8, PECTL 0xe0) fall > through to vtd_set_long() and log a guest error. > >Junjie Cao (2): > intel_iommu: fix guest-triggerable abort on oversized MMIO access > tests/qtest: add 8-byte MMIO access sweep for intel-iommu > > hw/i386/intel_iommu.c | 74 ++++++++++++++++++++++------------ > tests/qtest/intel-iommu-test.c | 30 ++++++++++++++ > 2 files changed, 79 insertions(+), 25 deletions(-) > > >base-commit: 5e61afe211e82a9af15a8794a0bd29bb574e953b >-- >2.43.0 For the whole series, Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com> Thanks Zhenzhong
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