Commit 3a2ffd3f authored by Josh Poimboeuf's avatar Josh Poimboeuf Committed by Jason Gunthorpe
Browse files

iommu: Convert unreachable() to BUG() 

Bare unreachable() should be avoided as it generates undefined behavior,
e.g. falling through to the next function.  Use BUG() instead so the
error is defined.

Fixes the following warnings:

  drivers/iommu/dma-iommu.o: warning: objtool: iommu_dma_sw_msi+0x92: can't find jump dest instruction at .text+0x54d5
  vmlinux.o: warning: objtool: iommu_dma_get_msi_page() falls through to next function __iommu_dma_unmap()

Link: https://patch.msgid.link/r/0c801ae017ec078cacd39f8f0898fc7780535f85.1743053325.git.jpoimboe@kernel.org


Reported-by: default avatarRandy Dunlap <rdunlap@infradead.org>
Closes: https://lore.kernel.org/314f8809-cd59-479b-97d7-49356bf1c8d1@infradead.org


Reported-by: default avatarPaul E. McKenney <paulmck@kernel.org>
Closes: https://lore.kernel.org/5dd1f35e-8ece-43b7-ad6d-86d02d2718f6@paulmck-laptop


Fixes: 6aa63a4e ("iommu: Sort out domain user data")
Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 6fc85bbb

drivers/iommu/dma-iommu.c

+2 −2
Original line number Diff line number Diff line
@@ -1762,7 +1762,7 @@ static size_t cookie_msi_granule(const struct iommu_domain *domain) 
	case IOMMU_COOKIE_DMA_MSI:

		return PAGE_SIZE;

	default:

		unreachable();

		BUG();

	};

}
@@ -1774,7 +1774,7 @@ static struct list_head *cookie_msi_pages(const struct iommu_domain *domain) 
	case IOMMU_COOKIE_DMA_MSI:

		return &domain->msi_cookie->msi_page_list;

	default:

		unreachable();

		BUG();

	};

}