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author | jhb <jhb@FreeBSD.org> | 2016-01-20 00:14:34 +0000 |
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committer | jhb <jhb@FreeBSD.org> | 2016-01-20 00:14:34 +0000 |
commit | aae5878eb3bca3067b218dc570c2bfcd310b3c02 (patch) | |
tree | 630b5949e3b75df563252a87bfbf5f79a26c7249 /sys/compat | |
parent | eef4b2b8aa5f8a9286884969f8f4041674fcb154 (diff) | |
download | FreeBSD-src-aae5878eb3bca3067b218dc570c2bfcd310b3c02.zip FreeBSD-src-aae5878eb3bca3067b218dc570c2bfcd310b3c02.tar.gz |
Initialize vm_page_prot to VM_MEMATTR_DEFAULT instead of 0.
If a driver's Linux mmap callback passed vm_page_prot through unchanged,
then linux_dev_mmap_single() would try to apply whatever VM_MEMATTR_xxx
value 0 is to the mapping. On x86, VM_MEMATTR_DEFAULT is the PAT value
for write-back (WB) which is 6, while 0 maps to the PAT value for
uncacheable (UC). Thus, any mmap request that did not explicitly set
page_prot was tried to map memory as UC triggering the warning in
sg_pager_getpages().
Tested by: np
Reported by: Krishnamraju Eraparaju @ Chelsio
MFC after: 3 days
Sponsored by: Chelsio Communications
Diffstat (limited to 'sys/compat')
-rw-r--r-- | sys/compat/linuxkpi/common/src/linux_compat.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/sys/compat/linuxkpi/common/src/linux_compat.c b/sys/compat/linuxkpi/common/src/linux_compat.c index 56080a4..9c73664 100644 --- a/sys/compat/linuxkpi/common/src/linux_compat.c +++ b/sys/compat/linuxkpi/common/src/linux_compat.c @@ -587,7 +587,7 @@ linux_dev_mmap_single(struct cdev *dev, vm_ooffset_t *offset, vma.vm_end = size; vma.vm_pgoff = *offset / PAGE_SIZE; vma.vm_pfn = 0; - vma.vm_page_prot = 0; + vma.vm_page_prot = VM_MEMATTR_DEFAULT; if (filp->f_op->mmap) { error = -filp->f_op->mmap(filp, &vma); if (error == 0) { |