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charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-03-10_03,2026-03-09_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 malwarescore=0 bulkscore=0 mlxlogscore=999 adultscore=0 phishscore=0 suspectscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2602130000 definitions=main-2603100143 X-Proofpoint-ORIG-GUID: SdiDRQwfvHOWLU1v5mqh24j0twY4lTuS X-Proofpoint-GUID: SdiDRQwfvHOWLU1v5mqh24j0twY4lTuS X-Authority-Analysis: v=2.4 cv=LeYxKzfi c=1 sm=1 tr=0 ts=69b0476c b=1 cx=c_pps a=e1sVV491RgrpLwSTMOnk8w==:117 a=e1sVV491RgrpLwSTMOnk8w==:17 a=IkcTkHD0fZMA:10 a=Yq5XynenixoA:10 a=VkNPw1HP01LnGYTKEx00:22 a=jiCTI4zE5U7BLdzWsZGv:22 a=o5oIOnhZENCTenyL_yNV:22 a=yPCof4ZbAAAA:8 a=ThXoxqst169cUD3MQKIA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 cc=ntf awl=host:13819 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMzEwMDE0MyBTYWx0ZWRfX83U6W0Xt6Xfm 4c/sHYC+UpC8XTtjYf8SJvssDTo8g/JzbLC9MceZpuwd79jwhCRI9upo5BufuXsfv7EC6oGznV2 0qUfwp54kmhG4UeTC9m2GIoUJj4zd3SXUQsoS9XOoxfU52QrU9E9qUG+UAMHFPxSXFh8oY6FZbx Tde8nGVY3Ku5fmlfaZ7sLB49XLAKaE1le7N0SEq6pbukbM9hjZ6v4wzsr4L5Zo4IAspSeIN0HwA 64W1Ui7RbKDMZ+XSsjJnJFif5oqkKij5X2s00c84qs+B0S7tn2bU8DDAqPlri8Q+/jCxJDkGW6p uPyDlLowJabvLzKpRiO8nChKqDIYJIOr74zIVIXLMORp0A/F452Gtecs0R73S4HXK668NXDPj7L DeiNuimcbxw44Q2ooeHhBQ5yXlXW7CHLYCSHW897nupTGczGTGqxUkmaumfaiUmH94XjJhmWE2l cpAmwpvi4nSGgnWsLaG6tjwMI1PahBOtrAJ1A2Og= After enabling CONFIG_GCOV_KERNEL and CONFIG_GCOV_PROFILE_ALL, following build failure is observed: In function 'amdv1pt_install_leaf_entry', inlined from '__do_map_single_page' at drivers/iommu/generic_pt/fmt/../= iommu_pt.h:650:3, inlined from '__map_single_page0' at drivers/iommu/generic_pt/fmt/../io= mmu_pt.h:661:1, inlined from 'pt_descend' at drivers/iommu/generic_pt/fmt/../pt_iter.h:= 391:9, inlined from '__do_map_single_page' at drivers/iommu/generic_pt/fmt/../= iommu_pt.h:657:10, inlined from '__map_single_page1.constprop' at drivers/iommu/generic_pt= /fmt/../iommu_pt.h:661:1: ././include/linux/compiler_types.h:706:45: error: call to '__compiletime_as= sert_71' declared with attribute error: FIELD_PREP: value too large for the= field 706 | _compiletime_assert(condition, msg, __compiletime_assert_, = __COUNTER__) | ...... drivers/iommu/generic_pt/fmt/amdv1.h:220:26: note: in expansion of macro 'F= IELD_PREP' 220 | FIELD_PREP(AMDV1PT_FMT_OA, | ^~~~~~~~~~ In the path '__do_map_single_page()', level 0 always invokes 'pt_install_leaf_entry(&pts, map->oa, PAGE_SHIFT, =E2=80=A6)'. At runtime t= hat lands in the 'if (oasz_lg2 =3D=3D isz_lg2)' arm of 'amdv1pt_install_leaf_en= try()'; the contiguous-only 'else' block is unreachable for 4=E2=80=AFKiB pages. With CONFIG_GCOV_KERNEL + CONFIG_GCOV_PROFILE_ALL, the extra instrumentation changes GCC's inlining so that the "dead" 'else' branch still gets instantiated. The compiler constant-folds the contiguous OA expression, runs the 'FIELD_PREP()' compile-time check, and produces: FIELD_PREP: value too large for the field gcov-enabled builds therefore fail even though the code path never executes. Fix this by keeping the compile-time guard on the NEXT_LEVEL field but encoding the OA field manually after a runtime 'FIELD_FIT()' check. We shift-and-mask the value ourselves, so the compiler no longer evaluates 'FIELD_PREP(AMDV1PT_FMT_OA, =E2=80=A6)' with constant inputs, while we pres= erve the range validation and resulting bit pattern. Fixes: 879ced2bab1b ("iommupt: Add the AMD IOMMU v1 page table format") Signed-off-by: Sherry Yang --- drivers/iommu/generic_pt/fmt/amdv1.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/generic_pt/fmt/amdv1.h b/drivers/iommu/generic_p= t/fmt/amdv1.h index aa8e1a8ec95f..c0a200afbe79 100644 --- a/drivers/iommu/generic_pt/fmt/amdv1.h +++ b/drivers/iommu/generic_pt/fmt/amdv1.h @@ -214,13 +214,14 @@ amdv1pt_install_leaf_entry(struct pt_state *pts, pt_o= addr_t oa, } else { unsigned int num_contig_lg2 =3D oasz_lg2 - isz_lg2; u64 *end =3D tablep + log2_to_int(num_contig_lg2); + pt_oaddr_t contig_oa =3D oalog2_to_int(oasz_lg2 - PT_GRANULE_LG2SZ - 1) = - 1; + + if (PT_WARN_ON(!FIELD_FIT(AMDV1PT_FMT_OA, contig_oa))) + return; =20 entry |=3D FIELD_PREP(AMDV1PT_FMT_NEXT_LEVEL, AMDV1PT_FMT_NL_SIZE) | - FIELD_PREP(AMDV1PT_FMT_OA, - oalog2_to_int(oasz_lg2 - PT_GRANULE_LG2SZ - - 1) - - 1); + (((u64)contig_oa << __bf_shf(AMDV1PT_FMT_OA)) & AMDV1PT_FMT_OA); =20 /* See amdv1pt_clear_entries() */ if (num_contig_lg2 <=3D ilog2(32)) { --=20 2.50.1