kmap_atomic() has been deprecated for a few years, and kmap_local_page() should be used instead, so replace it. Since the uprobes code relied on kmap_atomic() disabling page faults to access user pages, add the required calls to keep the existing behavior.
Signed-off-by: Carlos López <[email protected]> --- kernel/events/uprobes.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index d546d32390a8..38898435acfe 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -179,16 +179,24 @@ bool __weak is_trap_insn(uprobe_opcode_t *insn) void uprobe_copy_from_page(struct page *page, unsigned long vaddr, void *dst, int len) { - void *kaddr = kmap_atomic(page); + void *kaddr = kmap_local_page(page); + + pagefault_disable(); memcpy(dst, kaddr + (vaddr & ~PAGE_MASK), len); - kunmap_atomic(kaddr); + pagefault_enable(); + + kunmap_local(kaddr); } static void copy_to_page(struct page *page, unsigned long vaddr, const void *src, int len) { - void *kaddr = kmap_atomic(page); + void *kaddr = kmap_local_page(page); + + pagefault_disable(); memcpy(kaddr + (vaddr & ~PAGE_MASK), src, len); - kunmap_atomic(kaddr); + pagefault_enable(); + + kunmap_local(kaddr); } static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *insn, @@ -323,9 +331,10 @@ __update_ref_ctr(struct mm_struct *mm, unsigned long vaddr, short d) return ret == 0 ? -EBUSY : ret; } - kaddr = kmap_atomic(page); + kaddr = kmap_local_page(page); ptr = kaddr + (vaddr & ~PAGE_MASK); + pagefault_disable(); if (unlikely(*ptr + d < 0)) { pr_warn("ref_ctr going negative. vaddr: 0x%lx, " "curr val: %d, delta: %d\n", vaddr, *ptr, d); @@ -336,7 +345,8 @@ __update_ref_ctr(struct mm_struct *mm, unsigned long vaddr, short d) *ptr += d; ret = 0; out: - kunmap_atomic(kaddr); + pagefault_enable(); + kunmap_local(kaddr); put_page(page); return ret; } base-commit: f14faaf3a1fb3b9e4cf2e56269711fb85fba9458 -- 2.51.0
