diff options
| author | Dave Jiang <dave.jiang@intel.com> | 2018-07-26 16:37:15 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-10-20 09:48:53 +0200 |
| commit | 2a797fd8f8aeca8d120209d137b241d60bb48063 (patch) | |
| tree | a38223547b9aff375b82052eaa4d41fbc071412c /kernel/memremap.c | |
| parent | 8e6173c1246786d344548db3d10745ae250adb41 (diff) | |
mm: disallow mappings that conflict for devm_memremap_pages()
commit 15d36fecd0bdc7510b70a0e5ec6671140b3fce0c upstream.
When pmem namespaces created are smaller than section size, this can
cause an issue during removal and gpf was observed:
general protection fault: 0000 1 SMP PTI
CPU: 36 PID: 3941 Comm: ndctl Tainted: G W 4.14.28-1.el7uek.x86_64 #2
task: ffff88acda150000 task.stack: ffffc900233a4000
RIP: 0010:__put_page+0x56/0x79
Call Trace:
devm_memremap_pages_release+0x155/0x23a
release_nodes+0x21e/0x260
devres_release_all+0x3c/0x48
device_release_driver_internal+0x15c/0x207
device_release_driver+0x12/0x14
unbind_store+0xba/0xd8
drv_attr_store+0x27/0x31
sysfs_kf_write+0x3f/0x46
kernfs_fop_write+0x10f/0x18b
__vfs_write+0x3a/0x16d
vfs_write+0xb2/0x1a1
SyS_write+0x55/0xb9
do_syscall_64+0x79/0x1ae
entry_SYSCALL_64_after_hwframe+0x3d/0x0
Add code to check whether we have a mapping already in the same section
and prevent additional mappings from being created if that is the case.
Link: http://lkml.kernel.org/r/152909478401.50143.312364396244072931.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Robert Elliott <elliott@hpe.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel/memremap.c')
| -rw-r--r-- | kernel/memremap.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/kernel/memremap.c b/kernel/memremap.c index 2b136d4988f7..790ddf3bce19 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -355,10 +355,27 @@ void *devm_memremap_pages(struct device *dev, struct resource *res, struct dev_pagemap *pgmap; struct page_map *page_map; int error, nid, is_ram, i = 0; + struct dev_pagemap *conflict_pgmap; align_start = res->start & ~(SECTION_SIZE - 1); align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE) - align_start; + align_end = align_start + align_size - 1; + + conflict_pgmap = get_dev_pagemap(PHYS_PFN(align_start), NULL); + if (conflict_pgmap) { + dev_WARN(dev, "Conflicting mapping in same section\n"); + put_dev_pagemap(conflict_pgmap); + return ERR_PTR(-ENOMEM); + } + + conflict_pgmap = get_dev_pagemap(PHYS_PFN(align_end), NULL); + if (conflict_pgmap) { + dev_WARN(dev, "Conflicting mapping in same section\n"); + put_dev_pagemap(conflict_pgmap); + return ERR_PTR(-ENOMEM); + } + is_ram = region_intersects(align_start, align_size, IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE); @@ -396,7 +413,6 @@ void *devm_memremap_pages(struct device *dev, struct resource *res, mutex_lock(&pgmap_lock); error = 0; - align_end = align_start + align_size - 1; foreach_order_pgoff(res, order, pgoff) { struct dev_pagemap *dup; |