linux/kernel/dma, branch v5.15

Merge tag 'dma-mapping-5.15-2' of git://git.infradead.org/users/hch/dma-mapping

2021-10-20T20:16:51Z

Pull dma-mapping fixes from Christoph Hellwig: - fix more dma-debug fallout (Gerald Schaefer, Hamza Mahfooz) - fix a kerneldoc warning (Logan Gunthorpe) * tag 'dma-mapping-5.15-2' of git://git.infradead.org/users/hch/dma-mapping: dma-debug: teach add_dma_entry() about DMA_ATTR_SKIP_CPU_SYNC dma-debug: fix sg checks in debug_dma_map_sg() dma-mapping: fix the kerneldoc for dma_map_sgtable()

dma-debug: teach add_dma_entry() about DMA_ATTR_SKIP_CPU_SYNC

2021-10-18T10:46:45Z

Mapping something twice should be possible as long as, DMA_ATTR_SKIP_CPU_SYNC is passed to the strictly speaking second relevant mapping operation (that attempts to map the same thing). So, don't issue a warning if the specified condition is met in add_dma_entry(). Signed-off-by: Hamza Mahfooz Signed-off-by: Christoph Hellwig

dma-debug: fix sg checks in debug_dma_map_sg()

2021-10-11T11:43:31Z

The following warning occurred sporadically on s390: DMA-API: nvme 0006:00:00.0: device driver maps memory from kernel text or rodata [addr=0000000048cc5e2f] [len=131072] WARNING: CPU: 4 PID: 825 at kernel/dma/debug.c:1083 check_for_illegal_area+0xa8/0x138 It is a false-positive warning, due to broken logic in debug_dma_map_sg(). check_for_illegal_area() checks for overlay of sg elements with kernel text or rodata. It is called with sg_dma_len(s) instead of s->length as parameter. After the call to ->map_sg(), sg_dma_len() will contain the length of possibly combined sg elements in the DMA address space, and not the individual sg element length, which would be s->length. The check will then use the physical start address of an sg element, and add the DMA length for the overlap check, which could result in the false warning, because the DMA length can be larger than the actual single sg element length. In addition, the call to check_for_illegal_area() happens in the iteration over mapped_ents, which will not include all individual sg elements if any of them were combined in ->map_sg(). Fix this by using s->length instead of sg_dma_len(s). Also put the call to check_for_illegal_area() in a separate loop, iterating over all the individual sg elements ("nents" instead of "mapped_ents"). While at it, as suggested by Robin Murphy, also move check_for_stack() inside the new loop, as it is similarly concerned with validating the individual sg elements. Link: https://lore.kernel.org/lkml/20210705185252.4074653-1-gerald.schaefer@linux.ibm.com Fixes: 884d05970bfb ("dma-debug: use sg_dma_len accessor") Signed-off-by: Gerald Schaefer Signed-off-by: Christoph Hellwig

dma-mapping: fix the kerneldoc for dma_map_sgtable()

2021-10-11T11:43:04Z

htmldocs began producing the following warnings: kernel/dma/mapping.c:256: WARNING: Definition list ends without a blank line; unexpected unindent. kernel/dma/mapping.c:257: WARNING: Bullet list ends without a blank line; unexpected unindent. Reformatting the list without hyphens fixes the warnings and produces both a readable text and HTML output. Fixes: fffe3cc8c219 ("dma-mapping: allow map_sg() ops to return negative error code") Reported-by: Stephen Rothwell Signed-off-by: Logan Gunthorpe Signed-off-by: Christoph Hellwig

Merge tag 'dma-mapping-5.15-1' of git://git.infradead.org/users/hch/dma-mapping

2021-09-17T18:54:48Z

Pull dma-mapping fixes from Christoph Hellwig: - page align size in sparc32 arch_dma_alloc (Andreas Larsson) - tone down a new dma-debug message (Hamza Mahfooz) - fix the kerneldoc for dma_map_sg_attrs (me) * tag 'dma-mapping-5.15-1' of git://git.infradead.org/users/hch/dma-mapping: sparc32: page align size in arch_dma_alloc dma-debug: prevent an error message from causing runtime problems dma-mapping: fix the kerneldoc for dma_map_sg_attrs

dma-debug: prevent an error message from causing runtime problems

2021-09-13T16:29:24Z

For some drivers, that use the DMA API. This error message can be reached several millions of times per second, causing spam to the kernel's printk buffer and bringing the CPU usage up to 100% (so, it should be rate limited). However, since there is at least one driver that is in the mainline and suffers from the error condition, it is more useful to err_printk() here instead of just rate limiting the error message (in hopes that it will make it easier for other drivers that suffer from this issue to be spotted). Link: https://lkml.kernel.org/r/fd67fbac-64bf-f0ea-01e1-5938ccfab9d0@arm.com Reported-by: Jeremy Linton Signed-off-by: Hamza Mahfooz Signed-off-by: Christoph Hellwig

dma-mapping: fix the kerneldoc for dma_map_sg_attrs

2021-09-06T12:40:47Z

Add the missing description for the nents parameter, and fix a trivial misalignment. Fixes: fffe3cc8c219 ("dma-mapping: allow map_sg() ops to return negative error codes") Reported-by: Stephen Rothwell Signed-off-by: Christoph Hellwig

Merge branch 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb

2021-09-03T17:34:44Z

Pull swiotlb updates from Konrad Rzeszutek Wilk: "A new feature called restricted DMA pools. It allows SWIOTLB to utilize per-device (or per-platform) allocated memory pools instead of using the global one. The first big user of this is ARM Confidential Computing where the memory for DMA operations can be set per platform" * 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: (23 commits) swiotlb: use depends on for DMA_RESTRICTED_POOL of: restricted dma: Don't fail device probe on rmem init failure of: Move of_dma_set_restricted_buffer() into device.c powerpc/svm: Don't issue ultracalls if !mem_encrypt_active() s390/pv: fix the forcing of the swiotlb swiotlb: Free tbl memory in swiotlb_exit() swiotlb: Emit diagnostic in swiotlb_exit() swiotlb: Convert io_default_tlb_mem to static allocation of: Return success from of_dma_set_restricted_buffer() when !OF_ADDRESS swiotlb: add overflow checks to swiotlb_bounce swiotlb: fix implicit debugfs declarations of: Add plumbing for restricted DMA pool dt-bindings: of: Add restricted DMA pool swiotlb: Add restricted DMA pool initialization swiotlb: Add restricted DMA alloc/free support swiotlb: Refactor swiotlb_tbl_unmap_single swiotlb: Move alloc_size to swiotlb_find_slots swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing swiotlb: Update is_swiotlb_active to add a struct device argument swiotlb: Update is_swiotlb_buffer to add a struct device argument ...

swiotlb: use depends on for DMA_RESTRICTED_POOL

2021-08-31T18:48:14Z

Use depends on instead of select for DMA_RESTRICTED_POOL; otherwise it will make SWIOTLB user configurable and cause compile errors for some arch (e.g. mips). Fixes: 0b84e4f8b793 ("swiotlb: Add restricted DMA pool initialization") Acked-by: Will Deacon Reported-by: Guenter Roeck Signed-off-by: Claire Chang Signed-off-by: Konrad Rzeszutek Wilk

dma-mapping: make the global coherent pool conditional

2021-08-19T07:02:39Z

Only build the code to support the global coherent pool if support for it is enabled. Signed-off-by: Christoph Hellwig Tested-by: Dillon Min