From: Anders Roxell <anders.roxell@linaro.org> mainline inclusion from mainline-v5.3-rc5 commit 11f4fe9ba3c85a4efac7ec25e75056a9b612d9da category: bugfix bugzilla: 20500 CVE: NA ------------------------------------------------------------------------- Now that -Wimplicit-fallthrough is passed to GCC by default, the following warning shows up: ../drivers/iommu/arm-smmu-v3.c: In function ‘arm_smmu_write_strtab_ent’: ../drivers/iommu/arm-smmu-v3.c:1189:7: warning: this statement may fall through [-Wimplicit-fallthrough=] if (disable_bypass) ^ ../drivers/iommu/arm-smmu-v3.c:1191:3: note: here default: ^~~~~~~ Rework so that the compiler doesn't warn about fall-through. Make it clearer by calling 'BUG_ON()' when disable_bypass is set, and always 'break;' Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Reviewed-by: Hanjun Guo <guohanjun@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- drivers/iommu/arm-smmu-v3.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index e8f7bd3..5ee08ab 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -1226,8 +1226,8 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_device *smmu, u32 sid, ste_live = true; break; case STRTAB_STE_0_CFG_ABORT: - if (disable_bypass) - break; + BUG_ON(!disable_bypass); + break; default: BUG(); /* STE corruption */ } -- 1.8.3