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* lib/dma-debug.c: fix incorrect pfn calculationMiles Chen2017-11-181-2/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | dma-debug reports the following warning: WARNING: CPU: 3 PID: 298 at kernel-4.4/lib/dma-debug.c:604 debug _dma_assert_idle+0x1a8/0x230() DMA-API: cpu touching an active dma mapped cacheline [cln=0x00000882300] CPU: 3 PID: 298 Comm: vold Tainted: G W O 4.4.22+ #1 Hardware name: MT6739 (DT) Call trace: debug_dma_assert_idle+0x1a8/0x230 wp_page_copy.isra.96+0x118/0x520 do_wp_page+0x4fc/0x534 handle_mm_fault+0xd4c/0x1310 do_page_fault+0x1c8/0x394 do_mem_abort+0x50/0xec I found that debug_dma_alloc_coherent() and debug_dma_free_coherent() assume that dma_alloc_coherent() always returns a linear address. However it's possible that dma_alloc_coherent() returns a non-linear address. In this case, page_to_pfn(virt_to_page(virt)) will return an incorrect pfn. If the pfn is valid and mapped as a COW page, we will hit the warning when doing wp_page_copy(). Fix this by calculating pfn for linear and non-linear addresses. [miles.chen@mediatek.com: v4] Link: http://lkml.kernel.org/r/1510872972-23919-1-git-send-email-miles.chen@mediatek.com Link: http://lkml.kernel.org/r/1506484087-1177-1-git-send-email-miles.chen@mediatek.com Signed-off-by: Miles Chen <miles.chen@mediatek.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'dmaengine-4.12-rc1' of git://git.infradead.org/users/vkoul/slave-dmaLinus Torvalds2017-05-101-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull dmaengine updates from Vinod Koul: "This time again a smaller update consisting of: - support for TI DA8xx dma controller and updates to the cppi driver - updates on bunch of drivers like xilinx, pl08x, stm32-dma, mv_xor, ioat, dmatest" * tag 'dmaengine-4.12-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (35 commits) dmaengine: pl08x: remove lock documentation dmaengine: pl08x: fix pl08x_dma_chan_state documentation dmaengine: pl08x: Use the BIT() macro consistently dmaengine: pl080: Fix some missing kerneldoc dmaengine: pl080: Cut some unused defines dmaengine: dmatest: Add check for supported buffer count (sg_buffers) dmaengine: dmatest: Select DMA_ENGINE_RAID as its needed for the slave_sg test dmaengine: virt-dma: Convert to use list_for_each_entry_safe() dma-debug: use offset_in_page() macro dmaengine: mv_xor: use offset_in_page() macro dmaengine: dmatest: use offset_in_page() macro dmaengine: sun4i: fix invalid argument dmaengine: ioat: use setup_timer dmaengine: cppi41: Fix an Oops happening in cppi41_dma_probe() dmaengine: pl330: remove pdata based initialization dmaengine: cppi: fix build error due to bad variable dmaengine: imx-sdma: add 1ms delay to ensure SDMA channel is stopped dmaengine: cppi41: use managed functions devm_*() dmaengine: cppi41: fix cppi41_dma_tx_status() logic dmaengine: qcom_hidma: pause the channel on shutdown ...
| * dma-debug: use offset_in_page() macroGeliang Tang2017-04-241-2/+2
| | | | | | | | | | | | | | Use offset_in_page() macro instead of open-coding. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
* | lib/dma-debug.c: make locking work for RTPankaj Gupta2017-05-041-6/+2
|/ | | | | | | | | | | | | | | | | | | | Interrupt enable/disabled with spinlock is not a valid operation for RT as it can make executing tasks sleep from a non-sleepable context. So convert it to spin_lock_irq[save, restore]. Link: http://lkml.kernel.org/r/1492065666-3816-1-git-send-email-pagupta@redhat.com Signed-off-by: Pankaj Gupta <pagupta@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ville Syrjl <ville.syrjala@linux.intel.com> Cc: Miles Chen <miles.chen@mediatek.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | <linux/sched/task_stack.h> We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task_stack.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | <linux/sched/task.h> We are going to split <linux/sched/task.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* dma-debug: add comment for failed to check map errorMiles Chen2017-02-231-0/+5
| | | | | | | | | Add comment for failure to check a map error to help driver developers. Link: http://lkml.kernel.org/r/1484622289-22085-1-git-send-email-miles.chen@mediatek.com Signed-off-by: Miles Chen <miles.chen@mediatek.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'dmaengine-4.9-rc1' of git://git.infradead.org/users/vkoul/slave-dmaLinus Torvalds2016-10-071-2/+50
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull dmaengine updates from Vinod Koul: "This is bit large pile of code which bring in some nice additions: - Error reporting: we have added a new mechanism for users of dmaenegine to register a callback_result which tells them the result of the dma transaction. Right now only one user (ntb) is using it. - As we discussed on KS mailing list and pointed out NO_IRQ has no place in kernel, this also remove NO_IRQ from dmaengine subsystem (both arm and ppc users) - Support for IOMMU slave transfers and its implementation for arm. - To get better build coverage, enable COMPILE_TEST for bunch of driver, and fix the warning and sparse complaints on these. - Apart from above, usual updates spread across drivers" * tag 'dmaengine-4.9-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (169 commits) async_pq_val: fix DMA memory leak dmaengine: virt-dma: move function declarations dmaengine: omap-dma: Enable burst and data pack for SG DT: dmaengine: rcar-dmac: document R8A7743/5 support dmaengine: fsldma: Unmap region obtained by of_iomap dmaengine: jz4780: fix resource leaks on error exit return dma-debug: fix ia64 build, use PHYS_PFN dmaengine: coh901318: fix integer overflow when shifting more than 32 places dmaengine: edma: avoid uninitialized variable use dma-mapping: fix m32r build warning dma-mapping: fix ia64 build, use PHYS_PFN dmaengine: ti-dma-crossbar: enable COMPILE_TEST dmaengine: omap-dma: enable COMPILE_TEST dmaengine: edma: enable COMPILE_TEST dmaengine: ti-dma-crossbar: Fix of_device_id data parameter usage dmaengine: ti-dma-crossbar: Correct type for of_find_property() third parameter dmaengine/ARM: omap-dma: Fix the DMAengine compile test on non OMAP configs dmaengine: edma: Rename set_bits and remove unused clear_bits helper dmaengine: edma: Use correct type for of_find_property() third parameter dmaengine: edma: Fix of_device_id data parameter usage (legacy vs TPCC) ...
| * dma-debug: fix ia64 build, use PHYS_PFNNiklas Söderlund2016-09-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kbuild test robot reports: lib/dma-debug.c: In function 'debug_dma_map_resource': >> lib/dma-debug.c:1541:16: error: implicit declaration of function '__phys_to_pfn' [-Werror=implicit-function-declaration] entry->pfn = __phys_to_pfn(addr); ^~~~~~~~~~~~~ ia64 does not provide __phys_to_pfn(), use the PHYS_PFN() alias. Fixes: 0e74b34dfc3318bf ("dma-debug: add support for resource mappings") Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
| * dma-debug: add support for resource mappingsNiklas Söderlund2016-09-261-2/+50
| | | | | | | | | | | | | | | | | | | | | | A MMIO mapped resource can not be represented by a struct page so a new debug type is needed to handle this. This patch add such type and functionality to add/remove entries and how to translate them to a physical address. Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
* | dma-api: Teach the "DMA-from-stack" check about vmapped stacksAndy Lutomirski2016-08-241-6/+30
|/ | | | | | | | | | | | | | | | | | | | | | | | | | If we're using CONFIG_VMAP_STACK=y and we manage to point an sg entry at the stack, then either the sg page will be in highmem or sg_virt() will return the direct-map alias. In neither case will the existing check_for_stack() implementation realize that it's a stack page. Fix it by explicitly checking for stack pages. This has no effect by itself. It's broken out for ease of review. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/448460622731312298bf19dcbacb1606e75de7a9.1470907718.git.luto@kernel.org [ Minor edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* dma-debug: track bucket lock state for static checkersStephen Boyd2016-07-271-0/+2
| | | | | | | | | | | | | | | | get_hash_bucket() and put_hash_bucket() acquire and release the same spinlock, but this confuses static checkers such as sparse lib/dma-debug.c:254:27: warning: context imbalance in 'get_hash_bucket' - wrong count at exit lib/dma-debug.c:268:13: warning: context imbalance in 'put_hash_bucket' - unexpected unlock Add the appropriate acquire and release statements so that checkers can properly track the lock state. Link: http://lkml.kernel.org/r/20160701191552.24295-1-sboyd@codeaurora.org Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: avoid spinlock recursion when disabling dma-debugVille Syrjälä2016-05-271-1/+1
| | | | | | | | | | | | | With netconsole (at least) the pr_err("... disablingn") call can recurse back into the dma-debug code, where it'll try to grab free_entries_lock again. Avoid the problem by doing the printk after dropping the lock. Link: http://lkml.kernel.org/r/1463678421-18683-1-git-send-email-ville.syrjala@linux.intel.com Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: switch check from _text to _stextLaura Abbott2016-01-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | 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 <labbott@fedoraproject.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: Fix dma_debug_entry offset calculationDaniel Mentz2015-12-161-2/+2
| | | | | | | | | | | | | | | | | 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: <stable@vger.kernel.org> Fixes: 0abdd7a81b7e ("dma-debug: introduce debug_dma_assert_idle()") Signed-off-by: Daniel Mentz <danielmentz@google.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dma-debug: check nents in dma_sync_sg*Robin Murphy2015-11-071-0/+8
| | | | | | | | | | | | | | | Like dma_unmap_sg, dma_sync_sg* should be called with the original number of entries passed to dma_map_sg, so do the same check in the sync path as we do in the unmap path. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Sakari Ailus <sakari.ailus@iki.fi> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* debugfs: Pass bool pointer to debugfs_create_bool()Viresh Kumar2015-10-041-1/+1
| | | | | | | | | | | | | | | | | | | Its a bit odd that debugfs_create_bool() takes 'u32 *' as an argument, when all it needs is a boolean pointer. It would be better to update this API to make it accept 'bool *' instead, as that will make it more consistent and often more convenient. Over that bool takes just a byte. That required updates to all user sites as well, in the same commit updating the API. regmap core was also using debugfs_{read|write}_file_bool(), directly and variable types were updated for that to be bool as well. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* dma-debug: skip debug_dma_assert_idle() when disabledHaggai Eran2015-07-181-0/+3
| | | | | | | | | | | | | | | | | | | | | | | If dma-debug is disabled due to a memory error, DMA unmaps do not affect the dma_active_cacheline radix tree anymore, and debug_dma_assert_idle() can print false warnings. Disable debug_dma_assert_idle() when dma_debug_disabled() is true. Signed-off-by: Haggai Eran <haggaie@mellanox.com> Fixes: 0abdd7a81b7e ("dma-debug: introduce debug_dma_assert_idle()") Cc: Dan Williams <dan.j.williams@intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: James Bottomley <JBottomley@Parallels.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Horia Geanta <horia.geanta@freescale.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/dma-debug: fix bucket_find_contain()Sebastian Ott2015-04-171-1/+1
| | | | | | | | | | | | | | | | | | | | | bucket_find_contain() will search the bucket list for a dma_debug_entry. When the entry isn't found it needs to search other buckets too, since only the start address of a dma range is hashed (which might be in a different bucket). A copy of the dma_debug_entry is used to get the previous hash bucket but when its list is searched the original dma_debug_entry is to be used not its modified copy. This fixes false "device driver tries to sync DMA memory it has not allocated" warnings. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Horia Geanta <horia.geanta@freescale.com> Cc: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: prevent early callers from crashingFlorian Fainelli2014-12-111-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | dma_debug_init() is called by architecture specific code at different levels, but typically as a fs_initcall due to the debugfs initialization. Some platforms may have early callers of the DMA-API, running prior to the fs_initcall() level, which is not much of an issue unless CONFIG_DMA_API_DEBUG is set. When the DMA-API debugging facilities are turned on a caller will go through: debug_dma_map_{single,page} -> dma_mapping_error (inline function usually) -> debug_dma_mapping_error -> get_hash_bucket Calling get_hash_bucket() returns a valid hash value since we hash on high bits of the dma_addr cookie, but we will grab an unitialized spinlock, which typically won't crash but produce a warning, the real crash will however happen during the bucket list traversal because the list has not been initialized yet. An obvious solution is of course to move some of the offenders to run after the fs_initcall level, but since this might not always be an option, we add a flag "dma_debug_initialized" which is set to false by default, and set to true once dma_debug_init() has had a chance to run. The dma_debug_disabled() helper function previously introduced just needs to check for dma_debug_initialized to allow the caller to proceed or not. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Horia Geanta <horia.geanta@freescale.com> Cc: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: introduce dma_debug_disabledFlorian Fainelli2014-12-111-16/+21
| | | | | | | | | | | | | | | Add a helper function which returns whether the DMA debugging API is disabled, right now we only check for global_disable, but in order to accommodate early callers of the DMA-API, we will check for more initialization flags in the next patch. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Horia Geanta <horia.geanta@freescale.com> Cc: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: modify check_for_stack outputHoria Geanta2014-09-021-1/+1
| | | | | | | s/fromstack/from stack Signed-off-by: Horia Geanta <horia.geanta@freescale.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* dma debug: account for cachelines and read-only mappings in overlap trackingDan Williams2014-03-041-46/+85
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While debug_dma_assert_idle() checks if a given *page* is actively undergoing dma the valid granularity of a dma mapping is a *cacheline*. Sander's testing shows that the warning message "DMA-API: exceeded 7 overlapping mappings of pfn..." is falsely triggering. The test is simply mapping multiple cachelines in a given page. Ultimately we want overlap tracking to be valid as it is a real api violation, so we need to track active mappings by cachelines. Update the active dma tracking to use the page-frame-relative cacheline of the mapping as the key, and update debug_dma_assert_idle() to check for all possible mapped cachelines for a given page. However, the need to track active mappings is only relevant when the dma-mapping is writable by the device. In fact it is fairly standard for read-only mappings to have hundreds or thousands of overlapping mappings at once. Limiting the overlap tracking to writable (!DMA_TO_DEVICE) eliminates this class of false-positive overlap reports. Note, the radix gang lookup is sub-optimal. It would be best if it stopped fetching entries once the search passed a page boundary. Nevertheless, this implementation does not perturb the original net_dma failing case. That is to say the extra overhead does not show up in terms of making the failing case pass due to a timing change. References: http://marc.info/?l=linux-netdev&m=139232263419315&w=2 http://marc.info/?l=linux-netdev&m=139217088107122&w=2 Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Reported-by: Dave Jones <davej@redhat.com> Tested-by: Dave Jones <davej@redhat.com> Tested-by: Sander Eikelenboom <linux@eikelenboom.it> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Francois Romieu <romieu@fr.zoreil.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Wei Liu <wei.liu2@citrix.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: fix overlap detectionDan Williams2014-01-301-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | Commit 0abdd7a81b7e ("dma-debug: introduce debug_dma_assert_idle()") was reworked to expand the overlap counter to the full range expressable by 3 tag bits, but it has a thinko in treating the overlap counter as a pure reference count for the entry. Instead of deleting when the reference-count drops to zero, we need to delete when the overlap-count drops below zero. Also, when detecting overflow we can just test the overlap-count > MAX rather than applying special meaning to 0. Regression report available here: http://marc.info/?l=linux-netdev&m=139073373932386&w=2 This patch, now tested on the original net_dma case, sees the expected handful of reports before the eventual data corruption occurs. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Cc: Francois Romieu <romieu@fr.zoreil.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: introduce debug_dma_assert_idle()Dan Williams2014-01-221-13/+180
| | | | | | | | | | | | | | | | | | | | | | | Record actively mapped pages and provide an api for asserting a given page is dma inactive before execution proceeds. Placing debug_dma_assert_idle() in cow_user_page() flagged the violation of the dma-api in the NET_DMA implementation (see commit 77873803363c "net_dma: mark broken"). The implementation includes the capability to count, in a limited way, repeat mappings of the same page that occur without an intervening unmap. This 'overlap' counter is limited to the few bits of tag space in a radix tree. This mechanism is added to mitigate false negative cases where, for example, a page is dma mapped twice and debug_dma_assert_idle() is called after the page is un-mapped once. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: update DMA debug API to better handle multiple mappings of a bufferAlexander Duyck2013-03-231-5/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There were reports of the igb driver unmapping buffers without calling dma_mapping_error. On closer inspection issues were found in the DMA debug API and how it handled multiple mappings of the same buffer. The issue I found is the fact that the debug_dma_mapping_error would only set the map_err_type to MAP_ERR_CHECKED in the case that the was only one match for device and device address. However in the case of non-IOMMU, multiple addresses existed and as a result it was not setting this field once a second mapping was instantiated. I have resolved this by changing the search so that it instead will now set MAP_ERR_CHECKED on the first buffer that matches the device and DMA address that is currently in the state MAP_ERR_NOT_CHECKED. A secondary side effect of this patch is that in the case of multiple buffers using the same address only the last mapping will have a valid map_err_type. The previous mappings will all end up with map_err_type set to MAP_ERR_CHECKED because of the dma_mapping_error call in debug_dma_map_page. However this behavior may be preferable as it means you will likely only see one real error per multi-mapped buffer, versus the current behavior of multiple false errors mer multi-mapped buffer. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Cc: Joerg Roedel <joro@8bytes.org> Reviewed-by: Shuah Khan <shuah.khan@hp.com> Tested-by: Shuah Khan <shuah.khan@hp.com> Cc: Jakub Kicinski <kubakici@wp.pl> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: fix locking bug in check_unmap()Alexander Duyck2013-03-231-9/+12
| | | | | | | | | | | | | | | | | | In check_unmap() it is possible to get into a dead-locked state if dma_mapping_error is called. The problem is that the bucket is locked in check_unmap, and locked again by debug_dma_mapping_error which is called by dma_mapping_error. To resolve that we must release the lock on the bucket before making the call to dma_mapping_error. [akpm@linux-foundation.org: restore 80-col trickery to be consistent with the rest of the file] Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Cc: Joerg Roedel <joro@8bytes.org> Reviewed-by: Shuah Khan <shuah.khan@hp.com> Tested-by: Shuah Khan <shuah.khan@hp.com> Cc: Jakub Kicinski <kubakici@wp.pl> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: fix to not have dependency on get_dma_ops() interfaceShuah Khan2012-11-171-22/+7
| | | | | | | | | | | | | | | | | | dma-debug depends on get_dma_ops() interface. Several architectures do not define dma_ops and get_dma_ops(). When dma debug interfaces are used on an architecture (e.g: c6x) that doesn't define get_dmap_ops(), compilation fails. Changing dma-debug to call dma_mapping_error() instead of defining its own that calls get_dma_ops(), such that the internal use of dma_mapping_error() doesn't interfere with the debug_dma_mapping_error() interface's mapping error checks. Moving dma_mapping_error() checks in check_unmap() under the dma debug entry not found is sufficient to fix the problem. Reference: https://lkml.org/lkml/2012/10/26/367 Signed-off-by: Shuah Khan <shuah.khan@hp.com> Reported-by: Mark Salter <msalter@redhat.com> Signed-off-by: Joerg Roedel <joro@8bytes.org>
* dma-debug: New interfaces to debug dma mapping errorsShuah Khan2012-10-241-4/+67
| | | | | | | | | | | | | | | | | | | | Add dma-debug interface debug_dma_mapping_error() to debug drivers that fail to check dma mapping errors on addresses returned by dma_map_single() and dma_map_page() interfaces. This interface clears a flag set by debug_dma_map_page() to indicate that dma_mapping_error() has been called by the driver. When driver does unmap, debug_dma_unmap() checks the flag and if this flag is still set, prints warning message that includes call trace that leads up to the unmap. This interface can be called from dma_mapping_error() routines to enable dma mapping error check debugging. Tested: Intel iommu and swiotlb (iommu=soft) on x86-64 with CONFIG_DMA_API_DEBUG enabled and disabled. Signed-off-by: Shuah Khan <shuah.khan@hp.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* lib/dma-debug.c: fix __hash_bucket_find()Ming Lei2012-10-191-2/+2
| | | | | | | | | | | | | | | | | If there is only one match, the unique matched entry should be returned. Without the fix, the upcoming dma debug interfaces ("dma-debug: new interfaces to debug dma mapping errors") can't work reliably because only device and dma_addr are passed to dma_mapping_error(). Signed-off-by: Ming Lei <ming.lei@canonical.com> Reported-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Joerg Roedel <joerg.roedel@amd.com> Tested-by: Shuah Khan <shuah.khan@hp.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Jakub Kicinski <kubakici@wp.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-debug: Remove local BUS_NOTIFY_UNBOUND_DRIVER defineShuah Khan2012-10-021-5/+0
| | | | | | | | Remove local BUS_NOTIFY_UNBOUND_DRIVER define. This is not used since BUS_NOTIFY_UNBOUND_DRIVER is defined in include/linux/device.h Signed-off-by: Shuah Khan <shuah.khan@hp.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* dma-debug: debugfs_create_bool() takes a u32 pointerDan Carpenter2012-07-021-2/+2
| | | | | | | | | | Even though it has "bool" in the name, you have pass a u32 pointer to debugfs_create_bool(). Otherwise you get memory corruption in write_file_bool(). Fortunately in this case the corruption happens in an alignment hole between variables so it doesn't cause any problems. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* dma-debug: release free_entries_lock before saving stack traceJakub Kicinski2012-04-121-5/+5
| | | | | | | | Saving stack trace can take a while and once the entry is allocated free_entries_lock is no longer needed. Signed-off-by: Jakub Kicinski <kubakici@wp.pl> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* Remove useless get_driver()/put_driver() callsAlan Stern2012-01-251-2/+1
| | | | | | | | | | | | | | As part of the removal of get_driver()/put_driver(), this patch (as1512) gets rid of various useless and unnecessary calls in several drivers. In some cases it may be desirable to pin the driver by calling try_module_get(), but that can be done later. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: "David S. Miller" <davem@davemloft.net> CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: Michael Buesch <m@bues.ch> CC: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Fix comparison using wrong pointer variable in dma debug codeThomas Jarosch2011-11-211-1/+1
| | | | | | | | cppcheck reported: [lib/dma-debug.c:248] -> [lib/dma-debug.c:248]: (style) Same expression on both sides of '=='. Signed-off-by: Thomas Jarosch <thomas.jarosch@intra2net.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* lib: dma-debug needs export.h for EXPORT_SYMBOLPaul Gortmaker2011-11-011-0/+1
| | | | | | | There are no modular calls here, so just the minimal header for the EXPORT_SYMBOL macro will suffice. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* dma-debug: hash_bucket_find needs to allow for offsets within an entryNeil Horman2011-08-231-7/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Users of the pci_dma_sync_single_* api allow users to sync address ranges within the range of a mapped entry (i.e. you can dma map address X to dma_addr_t A and then pci_dma_sync_single on dma_addr_t A+1. The dma-debug library however assume dma syncs will always occur using the base address of a mapped region, and uses that assumption to find entries in its hash table. Since thats often (but not always the case), the dma debug library can give us false errors about missing entries, which are reported as syncing of memory not allocated by the driver. This was noted in the cxgb3 driver as this error: WARNING: at lib/dma-debug.c:902 check_sync+0xdd/0x48c() Hardware name: To be filled by O.E.M. cxgb3 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000fff97800] [size=1984 bytes] Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 uinput snd_hda_codec_intelhdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer e1000e snd soundcore r8169 cxgb3 iTCO_wdt snd_page_alloc mii shpchp i2c_i801 iTCO_vendor_support mdio microcode firewire_ohci firewire_core crc_itu_t ata_generic pata_acpi i915 drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan] Pid: 1818, comm: ifconfig Not tainted 2.6.35-0.23.rc3.git6.fc14.x86_64 #1 Call Trace: [<ffffffff81050f71>] warn_slowpath_common+0x85/0x9d [<ffffffff8105102c>] warn_slowpath_fmt+0x46/0x48 [<ffffffff8124658e>] ? check_sync+0x39/0x48c [<ffffffff8107c470>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81246632>] check_sync+0xdd/0x48c [<ffffffff81246ca6>] debug_dma_sync_single_for_device+0x3f/0x41 [<ffffffffa011615c>] ? pci_map_page+0x84/0x97 [cxgb3] [<ffffffffa0117bc3>] pci_dma_sync_single_for_device.clone.0+0x65/0x6e [cxgb3] [<ffffffffa0117ed1>] refill_fl+0x305/0x30a [cxgb3] [<ffffffffa011857d>] t3_sge_alloc_qset+0x6a7/0x821 [cxgb3] [<ffffffffa010a07b>] cxgb_up+0x4d0/0xe62 [cxgb3] [<ffffffff81086037>] ? __module_text_address+0x12/0x58 [<ffffffffa010aa4c>] cxgb_open+0x3f/0x309 [cxgb3] [<ffffffff813e9f6c>] __dev_open+0x8e/0xbc [<ffffffff813e7ca5>] __dev_change_flags+0xbe/0x142 [<ffffffff813e9ea8>] dev_change_flags+0x21/0x57 [<ffffffff81445937>] devinet_ioctl+0x29a/0x54b [<ffffffff811f9a87>] ? inode_has_perm+0xaa/0xce [<ffffffff81446ed2>] inet_ioctl+0x8f/0xa7 [<ffffffff813d683a>] sock_do_ioctl+0x29/0x48 [<ffffffff813d6c83>] sock_ioctl+0x213/0x222 [<ffffffff81137f78>] vfs_ioctl+0x32/0xa6 [<ffffffff811384e2>] do_vfs_ioctl+0x47a/0x4b3 [<ffffffff81138571>] sys_ioctl+0x56/0x79 [<ffffffff81009c32>] system_call_fastpath+0x16/0x1b ---[ end trace 69a4d4cc77b58004 ]--- (some edits by Joerg Roedel) Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jay Fenalson <fenlason@redhat.com> CC: Divy LeRay <divy@chelsio.com> CC: Stanislaw Gruszka <sgruszka@redhat.com> CC: Joerg Roedel <joerg.roedel@amd.com> CC: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* dma-debug: print information about leaked entryStanislaw Gruszka2011-04-071-5/+13
| | | | | | | | | When driver leak dma mapping, print additional information about one of leaked entries, to to help investigate problem. Patch should be useful for debugging drivers, which maps many different class of buffers. Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* llseek: automatically add .llseek fopArnd Bergmann2010-10-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
* dma-debug: Cleanup for copy-loop in filter_write()Dan Carpenter2010-04-071-1/+1
| | | | | | | | | | | Earlier in this function we set the last byte of "buf" to NULL so we always hit the break statement and "i" is never equal to NAME_MAX_LEN. This patch doesn't change how the driver works but it silences a Smatch warning and it makes it clearer that we don't write past the end of the array. Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* Merge branches 'amd-iommu/fixes' and 'dma-debug/fixes' into iommu/fixesJoerg Roedel2010-01-221-1/+1
|\
| * lib/dma-debug.c: mark file-local struct symbol static.Thiago Farina2010-01-221-1/+1
| | | | | | | | | | | | | | warning: symbol 'filter_fops' was not declared. Should it be static? Signed-off-by: Thiago Farina <tfransosi@gmail.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* | dma-debug: allow DMA_BIDIRECTIONAL mappings to be synced with ↵Krzysztof Halasa2010-01-111-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DMA_FROM_DEVICE and There is no need to perform full BIDIR sync (copying the buffers in case of swiotlb and similar schemes) if we know that the owner (CPU or device) hasn't altered the data. Addresses the false-positive reported at http://bugzilla.kernel.org/show_bug.cgi?id=14169 Signed-off-by: Krzysztof Halasa <khc@pm.waw.pl> Cc: David Miller <davem@davemloft.net> Cc: Joerg Roedel <joerg.roedel@amd.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | dma-debug: Fix bug causing build warningIngo Molnar2009-12-311-3/+2
|/ | | | | | | | | | | | | | | | | | | Stephen Rothwell reported the following build warning: lib/dma-debug.c: In function 'dma_debug_device_change': lib/dma-debug.c:680: warning: 'return' with no value, in function returning non-void Introduced by commit f797d9881b62c2ddb1d2e7bd80d87141949c84aa ("dma-debug: Do not add notifier when dma debugging is disabled"). Return 0 [notify-done] when disabled. (this is standard bus notifier behavior.) Signed-off-by: Shaun Ruffell <sruffell@digium.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@kernel.org> LKML-Reference: <20091231125624.GA14666@liondog.tnic> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* dma-debug: Do not add notifier when dma debugging is disabled.Shaun Ruffell2009-12-211-0/+5
| | | | | | | | | | | | | | | | | | | | If CONFIG_HAVE_DMA_API_DEBUG is defined and "dma_debug=off" is specified on the kernel command line, when you detach a driver from a device you can cause the following NULL pointer dereference: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<c0580d35>] dma_debug_device_change+0x5d/0x117 The problem is that the dma_debug_device_change notifier function is added to the bus notifier chain even though the dma_entry_hash array was never initialized. If dma debugging is disabled, this patch both prevents dma_debug_device_change notifiers from being added to the chain, and additionally ensures that the dma_debug_device_change notifier function is a no-op. Cc: stable@kernel.org Signed-off-by: Shaun Ruffell <sruffell@digium.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* tree-wide: fix assorted typos all over the placeAndré Goddard Rosa2009-12-041-1/+1
| | | | | | | | | | That is "success", "unknown", "through", "performance", "[re|un]mapping" , "access", "default", "reasonable", "[con]currently", "temperature" , "channel", "[un]used", "application", "example","hierarchy", "therefore" , "[over|under]flow", "contiguous", "threshold", "enough" and others. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* dma-debug: Fix compile warning with PAE enabledJoerg Roedel2009-10-291-2/+4
| | | | | | | | | | When PAE is enabled in the kernel configuration the size of phys_addr_t differs from the size of a void pointer. The gcc prints a warning about that in dma-debug code. This patch fixes the warning by converting the output to unsigned long long instead of a pointer. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
* dma-debug: Fix check_unmap null pointer dereferenceKyle McMartin2009-08-211-12/+16
| | | | | | | | | | | | | | | | | | | | | | While it's debatable whether or not a NULL device argument to the DMA API functions is valid... since it certainly isn't valid on devices with an IOMMU... dma-debug really shouldn't be dereferencing null pointers either. Guard against that in err_printk and the driver_filter functions. A Fedora rawhide user was seeing this in one of the dvb drivers resulting in an oops on boot. [ A patch has been sent for testing to the driver, but I feel the dma debugging support should be fixed as well. (There's still a pile of legacy garbage in the kernel passing null pointers to dma_{alloc,free}_*. :( ] Signed-off-by: Kyle McMartin <kyle@redhat.com> Cc: mchehab@infradead.org Cc: Joerg Roedel <joerg.roedel@amd.com> LKML-Reference: <20090820011708.GP25206@bombadil.infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* dma-debug: Fix the overlap() function to be correct and readableIngo Molnar2009-07-101-12/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Linus noticed how unclean and buggy the overlap() function is: - It uses convoluted (and bug-causing) positive checks for range overlap - instead of using a more natural negative check. - Even the positive checks are buggy: a positive intersection check has four natural cases while we checked only for three, missing the (addr < start && addr2 == end) case for example. - The variables are mis-named, making it non-obvious how the check was done. - It needlessly uses u64 instead of unsigned long. Since these are kernel memory pointers and we explicitly exclude highmem ranges anyway we cannot ever overflow 32 bits, even if we could. (and on 64-bit it doesnt matter anyway) All in one, this function needs a total revamp. I used Linus's suggestions minus the paranoid checks (we cannot overflow really because if we get totally bad DMA ranges passed far more things break in the systems than just DMA debugging). I also fixed a few other small details i noticed. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* dma-debug: Put all hash-chain locks into the same lock classIngo Molnar2009-06-171-1/+1
| | | | | | | | | | | | | | | | | | | | | Alan Cox reported that lockdep runs out of its stack-trace entries with certain configs: BUG: MAX_STACK_TRACE_ENTRIES too low This happens because there are 1024 hash buckets, each with a separate lock. Lockdep puts each lock into a separate lock class and tracks them independently. But in reality we never take more than one of the buckets, so they really belong into a single lock-class. Annotate the has bucket lock init accordingly. [ Impact: reduce the lockdep footprint of dma-debug ] Reported-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
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