From 0354aec19ce3d355c6213b0434064efc25c9b22c Mon Sep 17 00:00:00 2001 From: Daniel Mentz Date: Tue, 15 Dec 2015 17:38:48 -0800 Subject: dma-debug: Fix dma_debug_entry offset calculation dma-debug uses struct dma_debug_entry to keep track of dma coherent memory allocation requests. The virtual address is converted into a pfn and an offset. Previously, the offset was calculated using an incorrect bit mask. As a result, we saw incorrect error messages from dma-debug like the following: "DMA-API: exceeded 7 overlapping mappings of cacheline 0x03e00000" Cacheline 0x03e00000 does not exist on our platform. Cc: Fixes: 0abdd7a81b7e ("dma-debug: introduce debug_dma_assert_idle()") Signed-off-by: Daniel Mentz Signed-off-by: Dan Williams --- lib/dma-debug.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'lib/dma-debug.c') diff --git a/lib/dma-debug.c b/lib/dma-debug.c index 8855f019ebe8..d34bd24c2c84 100644 --- a/lib/dma-debug.c +++ b/lib/dma-debug.c @@ -1464,7 +1464,7 @@ void debug_dma_alloc_coherent(struct device *dev, size_t size, entry->type = dma_debug_coherent; entry->dev = dev; entry->pfn = page_to_pfn(virt_to_page(virt)); - entry->offset = (size_t) virt & PAGE_MASK; + entry->offset = (size_t) virt & ~PAGE_MASK; entry->size = size; entry->dev_addr = dma_addr; entry->direction = DMA_BIDIRECTIONAL; @@ -1480,7 +1480,7 @@ void debug_dma_free_coherent(struct device *dev, size_t size, .type = dma_debug_coherent, .dev = dev, .pfn = page_to_pfn(virt_to_page(virt)), - .offset = (size_t) virt & PAGE_MASK, + .offset = (size_t) virt & ~PAGE_MASK, .dev_addr = addr, .size = size, .direction = DMA_BIDIRECTIONAL, -- cgit v1.2.3 From ea535e418c01837d07b6c94e817540f50bfdadb0 Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Thu, 14 Jan 2016 15:16:50 -0800 Subject: dma-debug: switch check from _text to _stext In include/asm-generic/sections.h: /* * Usage guidelines: * _text, _data: architecture specific, don't use them in * arch-independent code * [_stext, _etext]: contains .text.* sections, may also contain * .rodata.* * and/or .init.* sections _text is not guaranteed across architectures. Architectures such as ARM may reuse parts which are not actually text and erroneously trigger a bug. Switch to using _stext which is guaranteed to contain text sections. Came out of https://lkml.kernel.org/g/<567B1176.4000106@redhat.com> Signed-off-by: Laura Abbott Reviewed-by: Kees Cook Cc: Russell King Cc: Arnd Bergmann Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/dma-debug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib/dma-debug.c') diff --git a/lib/dma-debug.c b/lib/dma-debug.c index d34bd24c2c84..4a1515f4b452 100644 --- a/lib/dma-debug.c +++ b/lib/dma-debug.c @@ -1181,7 +1181,7 @@ static inline bool overlap(void *addr, unsigned long len, void *start, void *end static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len) { - if (overlap(addr, len, _text, _etext) || + if (overlap(addr, len, _stext, _etext) || overlap(addr, len, __start_rodata, __end_rodata)) err_printk(dev, NULL, "DMA-API: device driver maps memory from kernel text or rodata [addr=%p] [len=%lu]\n", addr, len); } -- cgit v1.2.3