| Message ID | 1455632084-14666-1-git-send-email-m.szyprowski@samsung.com |
|---|---|
| State | Accepted |
| Commit | 722ec35f7faefcc34d12616eca7976a848870f9d |
| Headers | show |
Hello, On 2016-02-16 20:05, Robin Murphy wrote: > On 16/02/16 14:14, Marek Szyprowski wrote: >> This patch ensures that devices, which got registered before >> arch_initcall >> will be handled correctly by IOMMU-based DMA-mapping code. >> >> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> >> --- >> arch/arm64/mm/dma-mapping.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c >> index 573b1e6..ce6019f 100644 >> --- a/arch/arm64/mm/dma-mapping.c >> +++ b/arch/arm64/mm/dma-mapping.c >> @@ -928,6 +928,10 @@ static int __init __iommu_dma_init(void) >> ret = register_iommu_dma_ops_notifier(&platform_bus_type); >> if (!ret) >> ret = register_iommu_dma_ops_notifier(&amba_bustype); >> + >> + /* handle devices queued before this arch_initcall */ >> + if (!ret) >> + __iommu_attach_notifier(NULL, BUS_NOTIFY_ADD_DEVICE, NULL); > > Hmm, surely unless *all* the devices on the relevant buses are created > before arch_initcall level, then the next one is going to kick off the > notifier to walk the whole list anyway. Have you seen this being a > problem in practice? Yes, I've observed such situation, that's why I've posted this patch. I was really surprised that this code doesn't handle all cases. Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c index 573b1e6..ce6019f 100644 --- a/arch/arm64/mm/dma-mapping.c +++ b/arch/arm64/mm/dma-mapping.c @@ -928,6 +928,10 @@ static int __init __iommu_dma_init(void) ret = register_iommu_dma_ops_notifier(&platform_bus_type); if (!ret) ret = register_iommu_dma_ops_notifier(&amba_bustype); + + /* handle devices queued before this arch_initcall */ + if (!ret) + __iommu_attach_notifier(NULL, BUS_NOTIFY_ADD_DEVICE, NULL); return ret; } arch_initcall(__iommu_dma_init);
This patch ensures that devices, which got registered before arch_initcall will be handled correctly by IOMMU-based DMA-mapping code. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> --- arch/arm64/mm/dma-mapping.c | 4 ++++ 1 file changed, 4 insertions(+) -- 1.9.2 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel