From 1f78adfab379e53b0bd725b869061d9ba8055943 Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Fri, 12 Jul 2019 16:57:00 +0800 Subject: [PATCH] f2fs: disallow switching io_bits option during remount If IO alignment feature is turned on after remount, we didn't initialize mempool of it, it turns out we will encounter panic during IO submission due to access NULL mempool pointer. This feature should be set only at mount time, so simply deny configuring during remount. This fixes bug reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204135 Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/super.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 720f2e6d6f0a..3ae29d8fb18c 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -1522,6 +1522,7 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data) bool need_stop_gc = false; bool no_extent_cache = !test_opt(sbi, EXTENT_CACHE); bool disable_checkpoint = test_opt(sbi, DISABLE_CHECKPOINT); + bool no_io_align = !F2FS_IO_ALIGNED(sbi); bool checkpoint_changed; #ifdef CONFIG_QUOTA int i, j; @@ -1601,6 +1602,12 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data) goto restore_opts; } + if (no_io_align == !!F2FS_IO_ALIGNED(sbi)) { + err = -EINVAL; + f2fs_warn(sbi, "switch io_bits option is not allowed"); + goto restore_opts; + } + if ((*flags & SB_RDONLY) && test_opt(sbi, DISABLE_CHECKPOINT)) { err = -EINVAL; f2fs_warn(sbi, "disabling checkpoint not compatible with read-only");