From 5c08600547c059e3fd072995f9f367cdaf3c7d9d Mon Sep 17 00:00:00 2001 From: Eric Auger Date: Wed, 4 Apr 2018 22:30:50 +0200 Subject: [PATCH] vfio: Use a trace point when a RAM section cannot be DMA mapped MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 567b5b309abe ("vfio/pci: Relax DMA map errors for MMIO regions") added an error message if a passed memory section address or size is not aligned to the page size and thus cannot be DMA mapped. This patch fixes the trace by printing the region name and the memory region section offset within the address space (instead of offset_within_region). We also turn the error_report into a trace event. Indeed, In some cases, the traces can be confusing to non expert end-users and let think the use case does not work (whereas it works as before). This is the case where a BAR is successively mapped at different GPAs and its sections are not compatible with dma map. The listener is called several times and traces are issued for each intermediate mapping. The end-user cannot easily match those GPAs against the final GPA output by lscpi. So let's keep those information to informed users. In mid term, the plan is to advise the user about BAR relocation relevance. Fixes: 567b5b309abe ("vfio/pci: Relax DMA map errors for MMIO regions") Signed-off-by: Eric Auger Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Alexey Kardashevskiy Signed-off-by: Alex Williamson --- hw/vfio/common.c | 11 +++++------ hw/vfio/trace-events | 1 + 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/hw/vfio/common.c b/hw/vfio/common.c index 5e84716218..07ffa0ba10 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -548,12 +548,11 @@ static void vfio_listener_region_add(MemoryListener *listener, hwaddr pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1; if ((iova & pgmask) || (int128_get64(llsize) & pgmask)) { - error_report("Region 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx - " is not aligned to 0x%"HWADDR_PRIx - " and cannot be mapped for DMA", - section->offset_within_region, - int128_getlo(section->size), - pgmask + 1); + trace_vfio_listener_region_add_no_dma_map( + memory_region_name(section->mr), + section->offset_within_address_space, + int128_getlo(section->size), + pgmask + 1); return; } } diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events index 79f63a2ff6..20109cb758 100644 --- a/hw/vfio/trace-events +++ b/hw/vfio/trace-events @@ -90,6 +90,7 @@ vfio_iommu_map_notify(const char *op, uint64_t iova_start, uint64_t iova_end) "i vfio_listener_region_add_skip(uint64_t start, uint64_t end) "SKIPPING region_add 0x%"PRIx64" - 0x%"PRIx64 vfio_listener_region_add_iommu(uint64_t start, uint64_t end) "region_add [iommu] 0x%"PRIx64" - 0x%"PRIx64 vfio_listener_region_add_ram(uint64_t iova_start, uint64_t iova_end, void *vaddr) "region_add [ram] 0x%"PRIx64" - 0x%"PRIx64" [%p]" +vfio_listener_region_add_no_dma_map(const char *name, uint64_t iova, uint64_t size, uint64_t page_size) "Region \"%s\" 0x%"PRIx64" size=0x%"PRIx64" is not aligned to 0x%"PRIx64" and cannot be mapped for DMA" vfio_listener_region_del_skip(uint64_t start, uint64_t end) "SKIPPING region_del 0x%"PRIx64" - 0x%"PRIx64 vfio_listener_region_del(uint64_t start, uint64_t end) "region_del 0x%"PRIx64" - 0x%"PRIx64 vfio_disconnect_container(int fd) "close container->fd=%d"