From ae7871be189cb41184f1e05742b4a99e2c59774d Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Fri, 16 Dec 2016 14:28:41 +0100 Subject: swiotlb: Convert swiotlb_force from int to enum Convert the flag swiotlb_force from an int to an enum, to prepare for the advent of more possible values. Suggested-by: Konrad Rzeszutek Wilk Signed-off-by: Geert Uytterhoeven Signed-off-by: Konrad Rzeszutek Wilk --- lib/swiotlb.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'lib') diff --git a/lib/swiotlb.c b/lib/swiotlb.c index cb1b54ee8527..a32dce6d5101 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -53,7 +53,7 @@ */ #define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT) -int swiotlb_force; +enum swiotlb_force swiotlb_force; /* * Used to do a quick range check in swiotlb_tbl_unmap_single and @@ -107,7 +107,7 @@ setup_io_tlb_npages(char *str) if (*str == ',') ++str; if (!strcmp(str, "force")) - swiotlb_force = 1; + swiotlb_force = SWIOTLB_FORCE; return 0; } @@ -763,7 +763,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, * we can safely return the device addr and not worry about bounce * buffering it. */ - if (dma_capable(dev, dev_addr, size) && !swiotlb_force) + if (dma_capable(dev, dev_addr, size) && swiotlb_force != SWIOTLB_FORCE) return dev_addr; trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force); @@ -904,7 +904,7 @@ swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems, phys_addr_t paddr = sg_phys(sg); dma_addr_t dev_addr = phys_to_dma(hwdev, paddr); - if (swiotlb_force || + if (swiotlb_force == SWIOTLB_FORCE || !dma_capable(hwdev, dev_addr, sg->length)) { phys_addr_t map = map_single(hwdev, sg_phys(sg), sg->length, dir, attrs); -- cgit v1.3-18-gd494 From fff5d99225107f5f13fe4a9805adc2a1c4b5fb00 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Fri, 16 Dec 2016 14:28:42 +0100 Subject: swiotlb: Add swiotlb=noforce debug option On architectures like arm64, swiotlb is tied intimately to the core architecture DMA support. In addition, ZONE_DMA cannot be disabled. To aid debugging and catch devices not supporting DMA to memory outside the 32-bit address space, add a kernel command line option "swiotlb=noforce", which disables the use of bounce buffers. If specified, trying to map memory that cannot be used with DMA will fail, and a rate-limited warning will be printed. Note that io_tlb_nslabs is set to 1, which is the minimal supported value. Signed-off-by: Geert Uytterhoeven Signed-off-by: Konrad Rzeszutek Wilk --- Documentation/admin-guide/kernel-parameters.txt | 3 ++- include/linux/swiotlb.h | 1 + include/trace/events/swiotlb.h | 3 ++- lib/swiotlb.c | 18 ++++++++++++++++-- 4 files changed, 21 insertions(+), 4 deletions(-) (limited to 'lib') diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index be2d6d0a03a4..7d5f4f4cecfa 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3807,10 +3807,11 @@ it if 0 is given (See Documentation/cgroup-v1/memory.txt) swiotlb= [ARM,IA-64,PPC,MIPS,X86] - Format: { | force } + Format: { | force | noforce } -- Number of I/O TLB slabs force -- force using of bounce buffers even if they wouldn't be automatically used by the kernel + noforce -- Never use bounce buffers (for debugging) switches= [HW,M68k] diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index 71d104e4c849..d9c84a9cde3d 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -12,6 +12,7 @@ struct scatterlist; enum swiotlb_force { SWIOTLB_NORMAL, /* Default - depending on HW DMA mask etc. */ SWIOTLB_FORCE, /* swiotlb=force */ + SWIOTLB_NO_FORCE, /* swiotlb=noforce */ }; extern enum swiotlb_force swiotlb_force; diff --git a/include/trace/events/swiotlb.h b/include/trace/events/swiotlb.h index 5e2e30a7efce..288c0c54a2b4 100644 --- a/include/trace/events/swiotlb.h +++ b/include/trace/events/swiotlb.h @@ -39,7 +39,8 @@ TRACE_EVENT(swiotlb_bounced, __entry->size, __print_symbolic(__entry->swiotlb_force, { SWIOTLB_NORMAL, "NORMAL" }, - { SWIOTLB_FORCE, "FORCE" })) + { SWIOTLB_FORCE, "FORCE" }, + { SWIOTLB_NO_FORCE, "NO_FORCE" })) ); #endif /* _TRACE_SWIOTLB_H */ diff --git a/lib/swiotlb.c b/lib/swiotlb.c index a32dce6d5101..9def738af4f4 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -106,8 +106,12 @@ setup_io_tlb_npages(char *str) } if (*str == ',') ++str; - if (!strcmp(str, "force")) + if (!strcmp(str, "force")) { swiotlb_force = SWIOTLB_FORCE; + } else if (!strcmp(str, "noforce")) { + swiotlb_force = SWIOTLB_NO_FORCE; + io_tlb_nslabs = 1; + } return 0; } @@ -543,8 +547,15 @@ static phys_addr_t map_single(struct device *hwdev, phys_addr_t phys, size_t size, enum dma_data_direction dir, unsigned long attrs) { - dma_addr_t start_dma_addr = phys_to_dma(hwdev, io_tlb_start); + dma_addr_t start_dma_addr; + + if (swiotlb_force == SWIOTLB_NO_FORCE) { + dev_warn_ratelimited(hwdev, "Cannot do DMA to address %pa\n", + &phys); + return SWIOTLB_MAP_ERROR; + } + start_dma_addr = phys_to_dma(hwdev, io_tlb_start); return swiotlb_tbl_map_single(hwdev, start_dma_addr, phys, size, dir, attrs); } @@ -721,6 +732,9 @@ static void swiotlb_full(struct device *dev, size_t size, enum dma_data_direction dir, int do_panic) { + if (swiotlb_force == SWIOTLB_NO_FORCE) + return; + /* * Ran out of IOMMU space for this operation. This is very bad. * Unfortunately the drivers cannot handle this operation properly. -- cgit v1.3-18-gd494 From 7453c549f5f6485c0d79cad7844870dcc7d1b34d Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Tue, 20 Dec 2016 10:02:02 -0500 Subject: swiotlb: Export swiotlb_max_segment to users So they can figure out what is the optimal number of pages that can be contingously stitched together without fear of bounce buffer. We also expose an mechanism for sub-users of SWIOTLB API, such as Xen-SWIOTLB to set the max segment value. And lastly if swiotlb=force is set (which mandates we bounce buffer everything) we set max_segment so at least we can bounce buffer one 4K page instead of a giant 512KB one for which we may not have space. Signed-off-by: Konrad Rzeszutek Wilk Reported-and-Tested-by: Juergen Gross --- drivers/gpu/drm/i915/i915_gem.c | 11 +---------- drivers/xen/swiotlb-xen.c | 4 ++++ include/linux/swiotlb.h | 3 +++ lib/swiotlb.c | 26 ++++++++++++++++++++++++++ 4 files changed, 34 insertions(+), 10 deletions(-) (limited to 'lib') diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index d0dcaf35b429..115fa399608c 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2290,15 +2290,6 @@ unlock: mutex_unlock(&obj->mm.lock); } -static unsigned int swiotlb_max_size(void) -{ -#if IS_ENABLED(CONFIG_SWIOTLB) - return rounddown(swiotlb_nr_tbl() << IO_TLB_SHIFT, PAGE_SIZE); -#else - return 0; -#endif -} - static void i915_sg_trim(struct sg_table *orig_st) { struct sg_table new_st; @@ -2345,7 +2336,7 @@ i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj) GEM_BUG_ON(obj->base.read_domains & I915_GEM_GPU_DOMAINS); GEM_BUG_ON(obj->base.write_domain & I915_GEM_GPU_DOMAINS); - max_segment = swiotlb_max_size(); + max_segment = swiotlb_max_segment(); if (!max_segment) max_segment = rounddown(UINT_MAX, PAGE_SIZE); diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index aba12009422e..f905d6eeb048 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -275,6 +275,10 @@ retry: rc = 0; } else rc = swiotlb_late_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs); + + if (!rc) + swiotlb_set_max_segment(PAGE_SIZE); + return rc; error: if (repeat--) { diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index d9c84a9cde3d..4ee479f2f355 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -114,11 +114,14 @@ swiotlb_dma_supported(struct device *hwdev, u64 mask); #ifdef CONFIG_SWIOTLB extern void __init swiotlb_free(void); +unsigned int swiotlb_max_segment(void); #else static inline void swiotlb_free(void) { } +static inline unsigned int swiotlb_max_segment(void) { return 0; } #endif extern void swiotlb_print_info(void); extern int is_swiotlb_buffer(phys_addr_t paddr); +extern void swiotlb_set_max_segment(unsigned int); #endif /* __LINUX_SWIOTLB_H */ diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 9def738af4f4..975b8fc4f1e1 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -82,6 +82,12 @@ static phys_addr_t io_tlb_overflow_buffer; static unsigned int *io_tlb_list; static unsigned int io_tlb_index; +/* + * Max segment that we can provide which (if pages are contingous) will + * not be bounced (unless SWIOTLB_FORCE is set). + */ +unsigned int max_segment; + /* * We need to save away the original address corresponding to a mapped entry * for the sync operations. @@ -124,6 +130,20 @@ unsigned long swiotlb_nr_tbl(void) } EXPORT_SYMBOL_GPL(swiotlb_nr_tbl); +unsigned int swiotlb_max_segment(void) +{ + return max_segment; +} +EXPORT_SYMBOL_GPL(swiotlb_max_segment); + +void swiotlb_set_max_segment(unsigned int val) +{ + if (swiotlb_force == SWIOTLB_FORCE) + max_segment = 1; + else + max_segment = rounddown(val, PAGE_SIZE); +} + /* default to 64MB */ #define IO_TLB_DEFAULT_SIZE (64UL<<20) unsigned long swiotlb_size_or_default(void) @@ -205,6 +225,7 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) if (verbose) swiotlb_print_info(); + swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT); return 0; } @@ -283,6 +304,7 @@ swiotlb_late_init_with_default_size(size_t default_size) rc = swiotlb_late_init_with_tbl(vstart, io_tlb_nslabs); if (rc) free_pages((unsigned long)vstart, order); + return rc; } @@ -337,6 +359,8 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) late_alloc = 1; + swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT); + return 0; cleanup4: @@ -351,6 +375,7 @@ cleanup2: io_tlb_end = 0; io_tlb_start = 0; io_tlb_nslabs = 0; + max_segment = 0; return -ENOMEM; } @@ -379,6 +404,7 @@ void __init swiotlb_free(void) PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT)); } io_tlb_nslabs = 0; + max_segment = 0; } int is_swiotlb_buffer(phys_addr_t paddr) -- cgit v1.3-18-gd494 From ea07b862ac8ef9b8c8358517d2e39f847dda6659 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Fri, 6 Jan 2017 19:21:43 -0500 Subject: mm: workingset: fix use-after-free in shadow node shrinker Several people report seeing warnings about inconsistent radix tree nodes followed by crashes in the workingset code, which all looked like use-after-free access from the shadow node shrinker. Dave Jones managed to reproduce the issue with a debug patch applied, which confirmed that the radix tree shrinking indeed frees shadow nodes while they are still linked to the shadow LRU: WARNING: CPU: 2 PID: 53 at lib/radix-tree.c:643 delete_node+0x1e4/0x200 CPU: 2 PID: 53 Comm: kswapd0 Not tainted 4.10.0-rc2-think+ #3 Call Trace: delete_node+0x1e4/0x200 __radix_tree_delete_node+0xd/0x10 shadow_lru_isolate+0xe6/0x220 __list_lru_walk_one.isra.4+0x9b/0x190 list_lru_walk_one+0x23/0x30 scan_shadow_nodes+0x2e/0x40 shrink_slab.part.44+0x23d/0x5d0 shrink_node+0x22c/0x330 kswapd+0x392/0x8f0 This is the WARN_ON_ONCE(!list_empty(&node->private_list)) placed in the inlined radix_tree_shrink(). The problem is with 14b468791fa9 ("mm: workingset: move shadow entry tracking to radix tree exceptional tracking"), which passes an update callback into the radix tree to link and unlink shadow leaf nodes when tree entries change, but forgot to pass the callback when reclaiming a shadow node. While the reclaimed shadow node itself is unlinked by the shrinker, its deletion from the tree can cause the left-most leaf node in the tree to be shrunk. If that happens to be a shadow node as well, we don't unlink it from the LRU as we should. Consider this tree, where the s are shadow entries: root->rnode | [0 n] | | [s ] [sssss] Now the shadow node shrinker reclaims the rightmost leaf node through the shadow node LRU: root->rnode | [0 ] | [s ] Because the parent of the deleted node is the first level below the root and has only one child in the left-most slot, the intermediate level is shrunk and the node containing the single shadow is put in its place: root->rnode | [s ] The shrinker again sees a single left-most slot in a first level node and thus decides to store the shadow in root->rnode directly and free the node - which is a leaf node on the shadow node LRU. root->rnode | s Without the update callback, the freed node remains on the shadow LRU, where it causes later shrinker runs to crash. Pass the node updater callback into __radix_tree_delete_node() in case the deletion causes the left-most branch in the tree to collapse too. Also add warnings when linked nodes are freed right away, rather than wait for the use-after-free when the list is scanned much later. Fixes: 14b468791fa9 ("mm: workingset: move shadow entry tracking to radix tree exceptional tracking") Reported-by: Dave Chinner Reported-by: Hugh Dickins Reported-by: Andrea Arcangeli Reported-and-tested-by: Dave Jones Signed-off-by: Johannes Weiner Cc: Christoph Hellwig Cc: Chris Leech Cc: Lee Duncan Cc: Jan Kara Cc: Kirill A. Shutemov Cc: Matthew Wilcox Cc: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/radix-tree.h | 4 +++- lib/radix-tree.c | 11 +++++++++-- mm/workingset.c | 3 ++- 3 files changed, 14 insertions(+), 4 deletions(-) (limited to 'lib') diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h index 5dea8f6440e4..52bda854593b 100644 --- a/include/linux/radix-tree.h +++ b/include/linux/radix-tree.h @@ -306,7 +306,9 @@ void radix_tree_iter_replace(struct radix_tree_root *, void radix_tree_replace_slot(struct radix_tree_root *root, void **slot, void *item); void __radix_tree_delete_node(struct radix_tree_root *root, - struct radix_tree_node *node); + struct radix_tree_node *node, + radix_tree_update_node_t update_node, + void *private); void *radix_tree_delete_item(struct radix_tree_root *, unsigned long, void *); void *radix_tree_delete(struct radix_tree_root *, unsigned long); void radix_tree_clear_tags(struct radix_tree_root *root, diff --git a/lib/radix-tree.c b/lib/radix-tree.c index 6f382e07de77..0b92d605fb69 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -640,6 +640,7 @@ static inline void radix_tree_shrink(struct radix_tree_root *root, update_node(node, private); } + WARN_ON_ONCE(!list_empty(&node->private_list)); radix_tree_node_free(node); } } @@ -666,6 +667,7 @@ static void delete_node(struct radix_tree_root *root, root->rnode = NULL; } + WARN_ON_ONCE(!list_empty(&node->private_list)); radix_tree_node_free(node); node = parent; @@ -767,6 +769,7 @@ static void radix_tree_free_nodes(struct radix_tree_node *node) struct radix_tree_node *old = child; offset = child->offset + 1; child = child->parent; + WARN_ON_ONCE(!list_empty(&node->private_list)); radix_tree_node_free(old); if (old == entry_to_node(node)) return; @@ -1824,15 +1827,19 @@ EXPORT_SYMBOL(radix_tree_gang_lookup_tag_slot); * __radix_tree_delete_node - try to free node after clearing a slot * @root: radix tree root * @node: node containing @index + * @update_node: callback for changing leaf nodes + * @private: private data to pass to @update_node * * After clearing the slot at @index in @node from radix tree * rooted at @root, call this function to attempt freeing the * node and shrinking the tree. */ void __radix_tree_delete_node(struct radix_tree_root *root, - struct radix_tree_node *node) + struct radix_tree_node *node, + radix_tree_update_node_t update_node, + void *private) { - delete_node(root, node, NULL, NULL); + delete_node(root, node, update_node, private); } /** diff --git a/mm/workingset.c b/mm/workingset.c index 241fa5d6b3b2..abb58ffa3c64 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -473,7 +473,8 @@ static enum lru_status shadow_lru_isolate(struct list_head *item, if (WARN_ON_ONCE(node->exceptional)) goto out_invalid; inc_node_state(page_pgdat(virt_to_page(node)), WORKINGSET_NODERECLAIM); - __radix_tree_delete_node(&mapping->page_tree, node); + __radix_tree_delete_node(&mapping->page_tree, node, + workingset_update_node, mapping); out_invalid: spin_unlock(&mapping->tree_lock); -- cgit v1.3-18-gd494 From da0510c47519fe0999cffe316e1d370e29f952be Mon Sep 17 00:00:00 2001 From: Sudip Mukherjee Date: Tue, 10 Jan 2017 16:57:45 -0800 Subject: lib/Kconfig.debug: fix frv build failure The build of frv allmodconfig was failing with the errors like: /tmp/cc0JSPc3.s: Assembler messages: /tmp/cc0JSPc3.s:1839: Error: symbol `.LSLT0' is already defined /tmp/cc0JSPc3.s:1842: Error: symbol `.LASLTP0' is already defined /tmp/cc0JSPc3.s:1969: Error: symbol `.LELTP0' is already defined /tmp/cc0JSPc3.s:1970: Error: symbol `.LELT0' is already defined Commit 866ced950bcd ("kbuild: Support split debug info v4") introduced splitting the debug info and keeping that in a separate file. Somehow, the frv-linux gcc did not like that and I am guessing that instead of splitting it started copying. The first report about this is at: https://lists.01.org/pipermail/kbuild-all/2015-July/010527.html. I will try and see if this can work with frv and if still fails I will open a bug report with gcc. But meanwhile this is the easiest option to solve build failure of frv. Fixes: 866ced950bcd ("kbuild: Support split debug info v4") Link: http://lkml.kernel.org/r/1482062348-5352-1-git-send-email-sudipm.mukherjee@gmail.com Signed-off-by: Sudip Mukherjee Reported-by: Fengguang Wu Cc: Andi Kleen Cc: David Howells Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/Kconfig.debug | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index b06848a104e6..eb9e9a7870fa 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -164,7 +164,7 @@ config DEBUG_INFO_REDUCED config DEBUG_INFO_SPLIT bool "Produce split debuginfo in .dwo files" - depends on DEBUG_INFO + depends on DEBUG_INFO && !FRV help Generate debug info into separate .dwo files. This significantly reduces the build directory size for builds with DEBUG_INFO, -- cgit v1.3-18-gd494 From b9dc6f65bc5e232d1c05fe34b5daadc7e8bbf1fb Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 14 Jan 2017 19:33:08 -0500 Subject: fix a fencepost error in pipe_advance() The logics in pipe_advance() used to release all buffers past the new position failed in cases when the number of buffers to release was equal to pipe->buffers. If that happened, none of them had been released, leaving pipe full. Worse, it was trivial to trigger and we end up with pipe full of uninitialized pages. IOW, it's an infoleak. Cc: stable@vger.kernel.org # v4.9 Reported-by: "Alan J. Wylie" Tested-by: "Alan J. Wylie" Signed-off-by: Al Viro --- lib/iov_iter.c | 54 +++++++++++++++++++++++++++++++----------------------- 1 file changed, 31 insertions(+), 23 deletions(-) (limited to 'lib') diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 25f572303801..e68604ae3ced 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -730,43 +730,50 @@ size_t iov_iter_copy_from_user_atomic(struct page *page, } EXPORT_SYMBOL(iov_iter_copy_from_user_atomic); +static inline void pipe_truncate(struct iov_iter *i) +{ + struct pipe_inode_info *pipe = i->pipe; + if (pipe->nrbufs) { + size_t off = i->iov_offset; + int idx = i->idx; + int nrbufs = (idx - pipe->curbuf) & (pipe->buffers - 1); + if (off) { + pipe->bufs[idx].len = off - pipe->bufs[idx].offset; + idx = next_idx(idx, pipe); + nrbufs++; + } + while (pipe->nrbufs > nrbufs) { + pipe_buf_release(pipe, &pipe->bufs[idx]); + idx = next_idx(idx, pipe); + pipe->nrbufs--; + } + } +} + static void pipe_advance(struct iov_iter *i, size_t size) { struct pipe_inode_info *pipe = i->pipe; - struct pipe_buffer *buf; - int idx = i->idx; - size_t off = i->iov_offset, orig_sz; - if (unlikely(i->count < size)) size = i->count; - orig_sz = size; - if (size) { + struct pipe_buffer *buf; + size_t off = i->iov_offset, left = size; + int idx = i->idx; if (off) /* make it relative to the beginning of buffer */ - size += off - pipe->bufs[idx].offset; + left += off - pipe->bufs[idx].offset; while (1) { buf = &pipe->bufs[idx]; - if (size <= buf->len) + if (left <= buf->len) break; - size -= buf->len; + left -= buf->len; idx = next_idx(idx, pipe); } - buf->len = size; i->idx = idx; - off = i->iov_offset = buf->offset + size; - } - if (off) - idx = next_idx(idx, pipe); - if (pipe->nrbufs) { - int unused = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); - /* [curbuf,unused) is in use. Free [idx,unused) */ - while (idx != unused) { - pipe_buf_release(pipe, &pipe->bufs[idx]); - idx = next_idx(idx, pipe); - pipe->nrbufs--; - } + i->iov_offset = buf->offset + left; } - i->count -= orig_sz; + i->count -= size; + /* ... and discard everything past that point */ + pipe_truncate(i); } void iov_iter_advance(struct iov_iter *i, size_t size) @@ -826,6 +833,7 @@ void iov_iter_pipe(struct iov_iter *i, int direction, size_t count) { BUG_ON(direction != ITER_PIPE); + WARN_ON(pipe->nrbufs == pipe->buffers); i->type = direction; i->pipe = pipe; i->idx = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); -- cgit v1.3-18-gd494 From 602d9858f07c72eab64f5f00e2fae55f9902cfbe Mon Sep 17 00:00:00 2001 From: Nikita Yushchenko Date: Wed, 11 Jan 2017 21:56:31 +0300 Subject: swiotlb: ensure that page-sized mappings are page-aligned Some drivers do depend on page mappings to be page aligned. Swiotlb already enforces such alignment for mappings greater than page, extend that to page-sized mappings as well. Without this fix, nvme hits BUG() in nvme_setup_prps(), because that routine assumes page-aligned mappings. Signed-off-by: Nikita Yushchenko Reviewed-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Signed-off-by: Konrad Rzeszutek Wilk --- lib/swiotlb.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'lib') diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 975b8fc4f1e1..a8d74a733a38 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -483,11 +483,11 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT); /* - * For mappings greater than a page, we limit the stride (and - * hence alignment) to a page size. + * For mappings greater than or equal to a page, we limit the stride + * (and hence alignment) to a page size. */ nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; - if (size > PAGE_SIZE) + if (size >= PAGE_SIZE) stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT)); else stride = 1; -- cgit v1.3-18-gd494 From dd040b6f6d5630202e185399a2ff7ab356ed469c Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Tue, 24 Jan 2017 15:18:16 -0800 Subject: radix-tree: fix private list warnings The newly introduced warning in radix_tree_free_nodes() was testing the wrong variable; it should have been 'old' instead of 'node'. Fixes: ea07b862ac8e ("mm: workingset: fix use-after-free in shadow node shrinker") Link: http://lkml.kernel.org/r/20170118163746.GA32495@cmpxchg.org Signed-off-by: Matthew Wilcox Signed-off-by: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/radix-tree.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/radix-tree.c b/lib/radix-tree.c index 0b92d605fb69..84812a9fb16f 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -769,7 +769,7 @@ static void radix_tree_free_nodes(struct radix_tree_node *node) struct radix_tree_node *old = child; offset = child->offset + 1; child = child->parent; - WARN_ON_ONCE(!list_empty(&node->private_list)); + WARN_ON_ONCE(!list_empty(&old->private_list)); radix_tree_node_free(old); if (old == entry_to_node(node)) return; -- cgit v1.3-18-gd494 From 3277953de2f31dd03c6375e9a9f680ac37fc9d27 Mon Sep 17 00:00:00 2001 From: zhong jiang Date: Tue, 24 Jan 2017 15:18:52 -0800 Subject: mm: do not export ioremap_page_range symbol for external module Recently, I've found cases in which ioremap_page_range was used incorrectly, in external modules, leading to crashes. This can be partly attributed to the fact that ioremap_page_range is lower-level, with fewer protections, as compared to the other functions that an external module would typically call. Those include: ioremap_cache ioremap_nocache ioremap_prot ioremap_uc ioremap_wc ioremap_wt ...each of which wraps __ioremap_caller, which in turn provides a safer way to achieve the mapping. Therefore, stop EXPORT-ing ioremap_page_range. Link: http://lkml.kernel.org/r/1485173220-29010-1-git-send-email-zhongjiang@huawei.com Signed-off-by: zhong jiang Reviewed-by: John Hubbard Suggested-by: John Hubbard Acked-by: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/ioremap.c | 1 - 1 file changed, 1 deletion(-) (limited to 'lib') diff --git a/lib/ioremap.c b/lib/ioremap.c index 86c8911b0e3a..a3e14ce92a56 100644 --- a/lib/ioremap.c +++ b/lib/ioremap.c @@ -144,4 +144,3 @@ int ioremap_page_range(unsigned long addr, return err; } -EXPORT_SYMBOL_GPL(ioremap_page_range); -- cgit v1.3-18-gd494