This is a note to let you know that I've just added the patch titled
RISC-V: Acquire mmap lock before invoking walk_page_range
to the 5.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
risc-v-acquire-mmap-lock-before-invoking-walk_page_range.patch
and it can be found in the queue-5.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 0e2c09011d4de4161f615ff860a605a9186cf62a Mon Sep 17 00:00:00 2001
From: Atish Patra <atish.patra@xxxxxxx>
Date: Wed, 17 Jun 2020 13:37:32 -0700
Subject: RISC-V: Acquire mmap lock before invoking walk_page_range
From: Atish Patra <atish.patra@xxxxxxx>
commit 0e2c09011d4de4161f615ff860a605a9186cf62a upstream.
As per walk_page_range documentation, mmap lock should be acquired by the
caller before invoking walk_page_range. mmap_assert_locked gets triggered
without that. The details can be found here.
http://lists.infradead.org/pipermail/linux-riscv/2020-June/010335.html
Fixes: 395a21ff859c(riscv: add ARCH_HAS_SET_DIRECT_MAP support)
Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
Reviewed-by: Michel Lespinasse <walken@xxxxxxxxxx>
Reviewed-by: Zong Li <zong.li@xxxxxxxxxx>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/riscv/mm/pageattr.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
--- a/arch/riscv/mm/pageattr.c
+++ b/arch/riscv/mm/pageattr.c
@@ -151,6 +151,7 @@ int set_memory_nx(unsigned long addr, in
int set_direct_map_invalid_noflush(struct page *page)
{
+ int ret;
unsigned long start = (unsigned long)page_address(page);
unsigned long end = start + PAGE_SIZE;
struct pageattr_masks masks = {
@@ -158,11 +159,16 @@ int set_direct_map_invalid_noflush(struc
.clear_mask = __pgprot(_PAGE_PRESENT)
};
- return walk_page_range(&init_mm, start, end, &pageattr_ops, &masks);
+ mmap_read_lock(&init_mm);
+ ret = walk_page_range(&init_mm, start, end, &pageattr_ops, &masks);
+ mmap_read_unlock(&init_mm);
+
+ return ret;
}
int set_direct_map_default_noflush(struct page *page)
{
+ int ret;
unsigned long start = (unsigned long)page_address(page);
unsigned long end = start + PAGE_SIZE;
struct pageattr_masks masks = {
@@ -170,7 +176,11 @@ int set_direct_map_default_noflush(struc
.clear_mask = __pgprot(0)
};
- return walk_page_range(&init_mm, start, end, &pageattr_ops, &masks);
+ mmap_read_lock(&init_mm);
+ ret = walk_page_range(&init_mm, start, end, &pageattr_ops, &masks);
+ mmap_read_unlock(&init_mm);
+
+ return ret;
}
void __kernel_map_pages(struct page *page, int numpages, int enable)
Patches currently in stable-queue which might be from atish.patra@xxxxxxx are
queue-5.7/risc-v-acquire-mmap-lock-before-invoking-walk_page_range.patch
