diff options
| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2023-03-12 14:26:00 +0300 |
|---|---|---|
| committer | Dave Hansen <dave.hansen@linux.intel.com> | 2023-03-16 13:08:39 -0700 |
| commit | 428e106ae1ad4e45d3fd6978a753db475d0d0ec9 (patch) | |
| tree | 4bbc741cbd795dadc9f7543b8aa219cd3759db25 /mm/madvise.c | |
| parent | 82721d8b25d76c5a6f4c6cf4ce4e5b33788820a1 (diff) | |
mm: Introduce untagged_addr_remote()
untagged_addr() removes tags/metadata from the address and brings it to
the canonical form. The helper is implemented on arm64 and sparc. Both of
them do untagging based on global rules.
However, Linear Address Masking (LAM) on x86 introduces per-process
settings for untagging. As a result, untagged_addr() is now only
suitable for untagging addresses for the current proccess.
The new helper untagged_addr_remote() has to be used when the address
targets remote process. It requires the mmap lock for target mm to be
taken.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Alexander Potapenko <glider@google.com>
Link: https://lore.kernel.org/all/20230312112612.31869-6-kirill.shutemov%40linux.intel.com
Diffstat (limited to 'mm/madvise.c')
| -rw-r--r-- | mm/madvise.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/mm/madvise.c b/mm/madvise.c index 340125d08c03..d4b67f36f70f 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -1402,8 +1402,6 @@ int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int beh size_t len; struct blk_plug plug; - start = untagged_addr(start); - if (!madvise_behavior_valid(behavior)) return -EINVAL; @@ -1435,6 +1433,9 @@ int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int beh mmap_read_lock(mm); } + start = untagged_addr_remote(mm, start); + end = start + len; + blk_start_plug(&plug); error = madvise_walk_vmas(mm, start, end, behavior, madvise_vma_behavior); |