From 68dee8e2f2cacc54d038394e70d22411dee89da2 Mon Sep 17 00:00:00 2001 From: Nikola Pajkovsky Date: Tue, 15 Nov 2016 09:47:49 +0100 Subject: [PATCH] x86/pci-calgary: Fix iommu_free() comparison of unsigned expression >= 0 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit 8fd524b355da ("x86: Kill bad_dma_address variable") has killed bad_dma_address variable and used instead of macro DMA_ERROR_CODE which is always zero. Since dma_addr is unsigned, the statement dma_addr >= DMA_ERROR_CODE is always true, and not needed. arch/x86/kernel/pci-calgary_64.c: In function ‘iommu_free’: arch/x86/kernel/pci-calgary_64.c:299:2: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] if (unlikely((dma_addr >= DMA_ERROR_CODE) && (dma_addr < badend))) { Fixes: 8fd524b355da ("x86: Kill bad_dma_address variable") Signed-off-by: Nikola Pajkovsky Cc: iommu@lists.linux-foundation.org Cc: Jon Mason Cc: Muli Ben-Yehuda Link: http://lkml.kernel.org/r/7612c0f9dd7c1290407dbf8e809def922006920b.1479161177.git.npajkovsky@suse.cz Signed-off-by: Thomas Gleixner --- arch/x86/kernel/pci-calgary_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/pci-calgary_64.c b/arch/x86/kernel/pci-calgary_64.c index 5d400ba1349d..d47517941bbc 100644 --- a/arch/x86/kernel/pci-calgary_64.c +++ b/arch/x86/kernel/pci-calgary_64.c @@ -296,7 +296,7 @@ static void iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr, /* were we called with bad_dma_address? */ badend = DMA_ERROR_CODE + (EMERGENCY_PAGES * PAGE_SIZE); - if (unlikely((dma_addr >= DMA_ERROR_CODE) && (dma_addr < badend))) { + if (unlikely(dma_addr < badend)) { WARN(1, KERN_ERR "Calgary: driver tried unmapping bad DMA " "address 0x%Lx\n", dma_addr); return;