[PATCH v2 06/23] microblaze: allow pte_offset_map() to fail
From: Hugh Dickins <hughd@google.com>
Date: 2023-06-08 19:17:46
Also in:
linux-arm-kernel, linux-m68k, linux-mips, linux-mm, linux-riscv, linux-s390, linux-sh, lkml, sparclinux
Subsystem:
microblaze architecture, the rest · Maintainers:
Michal Simek, Linus Torvalds
In rare transient cases, not yet made possible, pte_offset_map() and pte_offset_map_lock() may not find a page table: handle appropriately. Signed-off-by: Hugh Dickins <hughd@google.com> --- arch/microblaze/kernel/signal.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/microblaze/kernel/signal.c b/arch/microblaze/kernel/signal.c
index c3aebec71c0c..c78a0ff48066 100644
--- a/arch/microblaze/kernel/signal.c
+++ b/arch/microblaze/kernel/signal.c@@ -194,7 +194,7 @@ static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, preempt_disable(); ptep = pte_offset_map(pmdp, address); - if (pte_present(*ptep)) { + if (ptep && pte_present(*ptep)) { address = (unsigned long) page_address(pte_page(*ptep)); /* MS: I need add offset in page */ address += ((unsigned long)frame->tramp) & ~PAGE_MASK;
@@ -203,7 +203,8 @@ static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, invalidate_icache_range(address, address + 8); flush_dcache_range(address, address + 8); } - pte_unmap(ptep); + if (ptep) + pte_unmap(ptep); preempt_enable(); if (err) return -EFAULT;
--
2.35.3