The use of kmap() and kmap_atomic() are being deprecated in favor of kmap_local_page(). With kmap_local_page(), the mappings are per thread, CPU local and not globally visible. Furthermore, the mappings can be acquired from any context (including interrupts). Therefore, use kmap_local_page() in exec.c because these mappings are per thread, CPU local, and not globally visible. Tested with xfstests on a QEMU + KVM 32-bits VM booting a kernel with HIGHMEM64GB enabled. Suggested-by: Ira Weiny <ira.weiny@xxxxxxxxx> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@xxxxxxxxx> --- fs/exec.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 0989fb8472a1..4a2129c0d422 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -583,11 +583,11 @@ static int copy_strings(int argc, struct user_arg_ptr argv, if (kmapped_page) { flush_dcache_page(kmapped_page); - kunmap(kmapped_page); + kunmap_local(kaddr); put_arg_page(kmapped_page); } kmapped_page = page; - kaddr = kmap(kmapped_page); + kaddr = kmap_local_page(kmapped_page); kpos = pos & PAGE_MASK; flush_arg_page(bprm, kpos, kmapped_page); } @@ -601,7 +601,7 @@ static int copy_strings(int argc, struct user_arg_ptr argv, out: if (kmapped_page) { flush_dcache_page(kmapped_page); - kunmap(kmapped_page); + kunmap_local(kaddr); put_arg_page(kmapped_page); } return ret; @@ -883,11 +883,11 @@ int transfer_args_to_stack(struct linux_binprm *bprm, for (index = MAX_ARG_PAGES - 1; index >= stop; index--) { unsigned int offset = index == stop ? bprm->p & ~PAGE_MASK : 0; - char *src = kmap(bprm->page[index]) + offset; + char *src = kmap_local_page(bprm->page[index]) + offset; sp -= PAGE_SIZE - offset; if (copy_to_user((void *) sp, src, PAGE_SIZE - offset) != 0) ret = -EFAULT; - kunmap(bprm->page[index]); + kunmap_local(src); if (ret) goto out; } @@ -1680,13 +1680,13 @@ int remove_arg_zero(struct linux_binprm *bprm) ret = -EFAULT; goto out; } - kaddr = kmap_atomic(page); + kaddr = kmap_local_page(page); for (; offset < PAGE_SIZE && kaddr[offset]; offset++, bprm->p++) ; - kunmap_atomic(kaddr); + kunmap_local(kaddr); put_arg_page(page); } while (offset == PAGE_SIZE); -- 2.36.1