Date:   Fri, 3 Feb 2023 09:00:18 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Rishabh Bhatnagar <risbhat@amazon.com>
Cc:     stable@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, mhocko@suse.co
Subject: Re: [PATCH stable 4.14 0/1] Fix ext4 xfstests failure
Message-ID: <Y9y/ElCYnDLTrLv6@kroah.com>
References: <20230131043815.14989-1-risbhat@amazon.com>
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On Tue, Jan 31, 2023 at 04:38:14AM +0000, Rishabh Bhatnagar wrote:
> While running xfstests on 4.14.304 version we see a warning being
> generated in one of ext4 tests with the following stack trace.
> 
> WARNING: CPU: 4 PID: 15332 at mm/util.c:414
> kvmalloc_node+0x67/0x70
> ext4_expand_extra_isize_ea+0x2b4/0x870 [ext4]
> __ext4_expand_extra_isize+0xcb/0x120 [ext4]
> ext4_mark_inode_dirty+0x1a5/0x1d0 [ext4]
> ext4_ext_truncate+0x1f/0x90 [ext4]
> ext4_truncate+0x363/0x400 [ext4]
> ext4_setattr+0x392/0xa00 [ext4]
> notify_change+0x300/0x420
> ? ext4_xattr_security_set+0x20/0x20 [ext4]
> do_truncate+0x75/0xc0
> ? ext4_release_file+0xa0/0xa0 [ext4]
> path_openat+0x737/0x16f0
> do_filp_open+0x9b/0x110
> ? __check_object_size+0xb4/0x190
> ? do_sys_open+0x1bd/0x250
> do_sys_open+0x1bd/0x250
> do_syscall_64+0x67/0x110
> entry_SYSCALL_64_after_hwframe+0x59/0xbe
> 
> It seems rebase to 4.14.304 brings a bunch of ext4 changes.
> Commit ext4: allocate extended attribute value in vmalloc area
> (73c44f61dab180b5f2dee9f15397aba36a75a882) tries to allocate buffer
> using kvmalloc with improper flags that generates this warning.
> To fix backport an upstream commit mm: kvmalloc does not
> fallback to vmalloc for incompatible gfp flags
> (170f26afa0481c72af93aa61b7398b5663451651). This removes the WARN_ON and
> fallsback to kmalloc if correct flags are not passed.
> 
> 
> Michal Hocko (1):
>   mm: kvmalloc does not fallback to vmalloc for incompatible gfp flags
> 
>  mm/util.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> -- 
> 2.38.1
> 

Now queued up, thanks.

greg k-h