Merge tag 'powerpc-7.0-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

torvalds · torvalds · commit 7ca6d1cfec80 · 2026-04-03T20:08:25.000-07:00
Pull powerpc fix from Madhavan Srinivasan:

 - fix iommu incorrectly bypassing DMA APIs

Thanks to Dan Horak, Gaurav Batra, and Ritesh Harjani (IBM).

* tag 'powerpc-7.0-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/powernv/iommu: iommu incorrectly bypass DMA APIs
diff --git a/arch/powerpc/kernel/dma-iommu.c b/arch/powerpc/kernel/dma-iommu.c
@@ -67,15 +67,15 @@ bool arch_dma_unmap_sg_direct(struct device *dev, struct scatterlist *sg,
 }
 bool arch_dma_alloc_direct(struct device *dev)
 {
-	if (dev->dma_ops_bypass)
+	if (dev->dma_ops_bypass && dev->bus_dma_limit)
 		return true;
 
 	return false;
 }
 
 bool arch_dma_free_direct(struct device *dev, dma_addr_t dma_handle)
 {
-	if (!dev->dma_ops_bypass)
+	if (!dev->dma_ops_bypass || !dev->bus_dma_limit)
 		return false;
 
 	return is_direct_handle(dev, dma_handle);

Original file line number	Diff line number	Diff line change
`@@ -67,15 +67,15 @@ bool arch_dma_unmap_sg_direct(struct device dev, struct scatterlist sg,`
`67`	`67`	`}`
`68`	`68`	`bool arch_dma_alloc_direct(struct device *dev)`
`69`	`69`	`{`
`70`		`- if (dev->dma_ops_bypass)`
	`70`	`+ if (dev->dma_ops_bypass && dev->bus_dma_limit)`
`71`	`71`	`return true;`
`72`	`72`
`73`	`73`	`return false;`
`74`	`74`	`}`
`75`	`75`
`76`	`76`	`bool arch_dma_free_direct(struct device *dev, dma_addr_t dma_handle)`
`77`	`77`	`{`
`78`		`- if (!dev->dma_ops_bypass)`
	`78`	`+ if (!dev->dma_ops_bypass \|\| !dev->bus_dma_limit)`
`79`	`79`	`return false;`
`80`	`80`
`81`	`81`	`return is_direct_handle(dev, dma_handle);`