Impact: extend on-kernel-stack DMA debug checks to all !highmem pages
We only checked dma_map_single() - extend it to dma_map_page()
and dma_map_sg() as well.
Also, fix dma_map_single() corner case bug: make sure we dont
stack-check highmem (not mapped) pages.
Reported-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: iommu@lists.linux-foundation.org
LKML-Reference: <1237818908-26516-1-git-send-email-joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: allow architectures to monitor busses for dma mem leakage
This patch adds checking code to detect if a device has pending DMA
operations when it is about to be unbound from its device driver.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Impact: get notified if a device dma maps illegal areas
This patch adds a check to print a warning message when a device driver
tries to map a memory area from the kernel text segment or rodata.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Impact: saves stacktrace of a dma mapping and prints it if there is an error
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This adds a function to dump the DMA mappings that the debugging code is
aware of -- either for a single device, or for _all_ devices.
This can be useful for debugging -- sticking a call to it in the DMA
page fault handler, for example, to see if the faulting address _should_
be mapped or not, and hence work out whether it's IOMMU bugs we're
seeing, or driver bugs.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Joerg Roedel