From 2c152d9da8fed3cade515eb5249fab805c87d831 Mon Sep 17 00:00:00 2001 From: Tong Tiangen Date: Wed, 1 Sep 2021 02:46:21 +0000 Subject: [PATCH] riscv/vdso: make arch_setup_additional_pages wait for mmap_sem for write killable [ Upstream commit 8bb0ab3ae7a4dbe6cf32deb830cf2bdbf5736867 ] riscv architectures relying on mmap_sem for write in their arch_setup_additional_pages. If the waiting task gets killed by the oom killer it would block oom_reaper from asynchronous address space reclaim and reduce the chances of timely OOM resolving. Wait for the lock in the killable mode and return with EINTR if the task got killed while waiting. Signed-off-by: Tong Tiangen Reviewed-by: Kefeng Wang Fixes: 76d2a0493a17 ("RISC-V: Init and Halt Code") Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin --- arch/riscv/kernel/vdso.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c index 3f1d35e7c98a..73d45931a053 100644 --- a/arch/riscv/kernel/vdso.c +++ b/arch/riscv/kernel/vdso.c @@ -65,7 +65,9 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, vdso_len = (vdso_pages + 1) << PAGE_SHIFT; - mmap_write_lock(mm); + if (mmap_write_lock_killable(mm)) + return -EINTR; + vdso_base = get_unmapped_area(NULL, 0, vdso_len, 0, 0); if (IS_ERR_VALUE(vdso_base)) { ret = vdso_base;