Commit d9a25490 authored by Zhihao Cheng's avatar Zhihao Cheng
Browse files

ubi: fastmap: Allocate memory with GFP_NOFS in ubi_update_fastmap 

mainline inclusion
from mainline-v6.7-rc1
commit a033ab4fec5fd9194d1b6c0306efbdc75f70b142
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I9195H
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a033ab4fec5fd9194d1b6c0306efbdc75f70b142



-------------------------------------------------

Function ubi_update_fastmap could be called in IO context, for example:
 ubifs_writepage
  do_writepage
   ubifs_jnl_write_data
    write_head
     ubifs_wbuf_write_nolock
      ubifs_leb_write
       ubi_leb_write
        ubi_eba_write_leb
	 try_write_vid_and_data
	  ubi_wl_get_peb
	   ubi_update_fastmap
	    erase_block

So it's better to allocate memory with GFP_NOFS mode, in case waiting
page writeback(dead loop).

Signed-off-by: default avatarZhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: default avatarRichard Weinberger <richard@nod.at>
parent 02f9f25b

drivers/mtd/ubi/fastmap.c

+5 −5
Original line number Diff line number Diff line
@@ -20,7 +20,7 @@ static inline unsigned long *init_seen(struct ubi_device *ubi) 
	if (!ubi_dbg_chk_fastmap(ubi))

		return NULL;



	ret = bitmap_zalloc(ubi->peb_count, GFP_KERNEL);

	ret = bitmap_zalloc(ubi->peb_count, GFP_NOFS);

	if (!ret)

		return ERR_PTR(-ENOMEM);
@@ -105,7 +105,7 @@ static struct ubi_vid_io_buf *new_fm_vbuf(struct ubi_device *ubi, int vol_id) 
	struct ubi_vid_io_buf *new;

	struct ubi_vid_hdr *vh;



	new = ubi_alloc_vid_buf(ubi, GFP_KERNEL);

	new = ubi_alloc_vid_buf(ubi, GFP_NOFS);

	if (!new)

		goto out;
@@ -1392,7 +1392,7 @@ static int erase_block(struct ubi_device *ubi, struct ubi_wl_entry *e) 
	struct ubi_ec_hdr *ec_hdr;

	long long ec = e->ec;



	ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);

	ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS);

	if (!ec_hdr)

		return -ENOMEM;
@@ -1448,7 +1448,7 @@ static int invalidate_fastmap(struct ubi_device *ubi) 
	ubi->fm = NULL;



	ret = -ENOMEM;

	fm = kzalloc(sizeof(*fm), GFP_KERNEL);

	fm = kzalloc(sizeof(*fm), GFP_NOFS);

	if (!fm)

		goto out;
@@ -1537,7 +1537,7 @@ int ubi_update_fastmap(struct ubi_device *ubi) 
		return 0;

	}



	new_fm = kzalloc(sizeof(*new_fm), GFP_KERNEL);

	new_fm = kzalloc(sizeof(*new_fm), GFP_NOFS);

	if (!new_fm) {

		up_write(&ubi->fm_eba_sem);

		up_write(&ubi->work_sem);