Messages in this thread Patch in this message | | | From | Daniel Vetter <> | Subject | [PATCH] io-mapping: ensure io_mapping_map_atomic _is_ atomic | Date | Thu, 15 Sep 2011 20:48:07 +0200 |
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For the !HAVE_ATOMIC_IOMAP case the stub functions did not call pagefault_disable/_enable. The i915 driver relies on the map actually being atomic, otherwise it can deadlock with it's own pagefault handler in the gtt pwrite fastpath.
This is exercised by gem_mmap_gtt from the intel-gpu-toosl gem testsuite.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=38115 Cc: stable@kernel.org Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> --- include/linux/io-mapping.h | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/include/linux/io-mapping.h b/include/linux/io-mapping.h index 8cdcc2a1..6b3bef1 100644 --- a/include/linux/io-mapping.h +++ b/include/linux/io-mapping.h @@ -138,12 +138,14 @@ static inline void __iomem * io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset) { + pagefault_disable(); return ((char __force __iomem *) mapping) + offset; } static inline void io_mapping_unmap_atomic(void __iomem *vaddr) { + pagefault_enable(); } /* Non-atomic map/unmap */ -- 1.7.6
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