diff options
| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2015-11-23 09:04:05 +0100 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2015-11-23 09:04:05 +0100 |
| commit | 92907cbbef8625bb3998d1eb385fc88f23c97a3f (patch) | |
| tree | 15626ff9287e37c3cb81c7286d6db5a7fd77c854 /mm/maccess.c | |
| parent | 15fbfccfe92c62ae8d1ecc647c44157ed01ac02e (diff) | |
| parent | 1ec218373b8ebda821aec00bb156a9c94fad9cd4 (diff) | |
Merge tag 'v4.4-rc2' into drm-intel-next-queued
Linux 4.4-rc2
Backmerge to get at
commit 1b0e3a049efe471c399674fd954500ce97438d30
Author: Imre Deak <imre.deak@intel.com>
Date: Thu Nov 5 23:04:11 2015 +0200
drm/i915/skl: disable display side power well support for now
so that we can proplery re-eanble skl power wells in -next.
Conflicts are just adjacent lines changed, except for intel_fbdev.c
where we need to interleave the changs. Nothing nefarious.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Diffstat (limited to 'mm/maccess.c')
| -rw-r--r-- | mm/maccess.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/mm/maccess.c b/mm/maccess.c index 34fe24759ed1..d159b1c96e48 100644 --- a/mm/maccess.c +++ b/mm/maccess.c @@ -13,6 +13,11 @@ * * Safely read from address @src to the buffer at @dst. If a kernel fault * happens, handle that and return -EFAULT. + * + * We ensure that the copy_from_user is executed in atomic context so that + * do_page_fault() doesn't attempt to take mmap_sem. This makes + * probe_kernel_read() suitable for use within regions where the caller + * already holds mmap_sem, or other locks which nest inside mmap_sem. */ long __weak probe_kernel_read(void *dst, const void *src, size_t size) @@ -99,5 +104,5 @@ long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count) pagefault_enable(); set_fs(old_fs); - return ret < 0 ? ret : src - unsafe_addr; + return ret ? -EFAULT : src - unsafe_addr; } |