linux-toradex.git/lib/dma-debug.c, branch v2.6.30.2

dma-debug: fix off-by-one error in overlap function

2009-07-20T03:38:51+00:00

commit c79ee4e466dd12347f112e2af306dca35198458f upstream.

This patch fixes a bug in the overlap function which returned true if
one region ends exactly before the second region begins. This is no
overlap but the function returned true in that case.

Reported-by: Andrew Randrianasulu 
Signed-off-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

dma-debug: change hash_bucket_find from first-fit to best-fit

2009-07-02T23:49:44+00:00

commit 7caf6a49bb17d0377210693af5737563b31aa5ee upstream.

Some device drivers map the same physical address multiple times to a
dma address. Without an IOMMU this results in the same dma address being
put into the dma-debug hash multiple times. With a first-fit match in
hash_bucket_find() this function may return the wrong dma_debug_entry.

This can result in false positive warnings. This patch fixes it by
changing the first-fit behavior of hash_bucket_find() into a best-fit
algorithm.

Reported-by: Torsten Kaiser 
Reported-by: FUJITA Tomonori 
Signed-off-by: Joerg Roedel 
Cc: lethal@linux-sh.org
Cc: just.for.lkml@googlemail.com
Cc: hancockrwd@gmail.com
Cc: jens.axboe@oracle.com
Cc: bharrosh@panasas.com
Cc: FUJITA Tomonori 
Cc: Linus Torvalds 
LKML-Reference: <20090605104132.GE24836@amd.com>
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

dma-debug: remove broken dma memory leak detection for 2.6.30

2009-04-26T16:23:56+00:00

The feature needs some more work because the notfier which is used to
check for pending allocations is called before the device drivers
->remove() function. Therefore this feature reports false positives.

A real fix for this issue is to introduce a new notifier event which sent
_after_ the driver has deinitialized itself. That will done for the next
kernel version.

[ Impact: reduce the scope of CONFIG_DMA_API_DEBUG=y checks ]

Signed-off-by: Joerg Roedel 
Cc: iommu@lists.linux-foundation.org
LKML-Reference: <1240576557-22442-1-git-send-email-joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar

dma-debug: fix printk formats (i386)

2009-03-30T21:28:59+00:00

Fix printk format warnings in dma-debug:

  lib/dma-debug.c:645: warning: format '%016llx' expects type 'long long unsigned int', but argument 6 has type 'dma_addr_t'
  lib/dma-debug.c:662: warning: format '%016llx' expects type 'long long unsigned int', but argument 6 has type 'dma_addr_t'
  lib/dma-debug.c:676: warning: format '%016llx' expects type 'long long unsigned int', but argument 6 has type 'dma_addr_t'
  lib/dma-debug.c:686: warning: format '%016llx' expects type 'long long unsigned int', but argument 6 has type 'dma_addr_t'

Signed-off-by: Randy Dunlap 
Signed-off-by: Linus Torvalds

dma-debug: make memory range checks more consistent

2009-03-24T07:39:32+00:00

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 
Signed-off-by: Joerg Roedel 
Cc: iommu@lists.linux-foundation.org
LKML-Reference: <1237818908-26516-1-git-send-email-joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar

dma-debug: warn of unmapping an invalid dma address

2009-03-19T07:39:48+00:00

Impact: extend DMA-debug checks

Calling dma_unmap families against an invalid dma address should be a
bug.

Signed-off-by: FUJITA Tomonori 
Cc: Joerg Roedel 
LKML-Reference: <20090319103743N.fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar

dma-debug: add a check dma memory leaks

2009-03-17T11:56:49+00:00

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

dma-debug: add checks for kernel text and rodata

2009-03-17T11:56:48+00:00

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

dma-debug: print stacktrace of mapping path on unmap error

2009-03-17T11:56:48+00:00

Impact: saves stacktrace of a dma mapping and prints it if there is an  error

Signed-off-by: David Woodhouse 
Signed-off-by: Joerg Roedel

dma-debug: add function to dump dma mappings

2009-03-17T11:56:39+00:00

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