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[RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure

Started bymhocko@kernel.org
First post2015-08-05 12:00 +0200
Last post2015-08-18 12:40 +0200
Articles 7 — 5 participants

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  [RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure mhocko@kernel.org - 2015-08-05 12:00 +0200
    Re: [RFC 4/8] jbd, jbd2: Do not fail journal because of  frozen_buffer allocation failure Jan Kara <jack@suse.cz> - 2015-08-05 13:50 +0200
    Re: [RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure Greg Thelen <gthelen@google.com> - 2015-08-05 18:50 +0200
      Re: [RFC 4/8] jbd, jbd2: Do not fail journal because of  frozen_buffer allocation failure Michal Hocko <mhocko@kernel.org> - 2015-08-12 11:20 +0200
        Re: [RFC 4/8] jbd, jbd2: Do not fail journal because of  frozen_buffer allocation failure Theodore Ts'o <tytso@mit.edu> - 2015-08-15 16:00 +0200
          Re: [RFC 4/8] jbd, jbd2: Do not fail journal because of  frozen_buffer allocation failure Michal Hocko <mhocko@kernel.org> - 2015-08-18 12:40 +0200
    [RFC -v2 4/8] jbd, jbd2: Do not fail journal because of  frozen_buffer allocation failure Michal Hocko <mhocko@kernel.org> - 2015-08-18 12:40 +0200

#1200600 — [RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure

Frommhocko@kernel.org
Date2015-08-05 12:00 +0200
Subject[RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure
Message-ID<pU3Em-66q-9@gated-at.bofh.it>
From: Michal Hocko <mhocko@suse.com>

Journal transaction might fail prematurely because the frozen_buffer
is allocated by GFP_NOFS request:
[   72.440013] do_get_write_access: OOM for frozen_buffer
[   72.440014] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
[   72.440015] EXT4-fs error (device sda1) in ext4_reserve_inode_write:4735: Out of memory
(...snipped....)
[   72.495559] do_get_write_access: OOM for frozen_buffer
[   72.495560] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
[   72.496839] do_get_write_access: OOM for frozen_buffer
[   72.496841] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
[   72.505766] Aborting journal on device sda1-8.
[   72.505851] EXT4-fs (sda1): Remounting filesystem read-only

This wasn't a problem until "mm: page_alloc: do not lock up GFP_NOFS
allocations upon OOM" because small GPF_NOFS allocations never failed.
This allocation seems essential for the journal and GFP_NOFS is too
restrictive to the memory allocator so let's use __GFP_NOFAIL here to
emulate the previous behavior.

jbd code has the very same issue so let's do the same there as well.

Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 fs/jbd/transaction.c  | 11 +----------
 fs/jbd2/transaction.c | 14 +++-----------
 2 files changed, 4 insertions(+), 21 deletions(-)

diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
index 1695ba8334a2..bf7474deda2f 100644
--- a/fs/jbd/transaction.c
+++ b/fs/jbd/transaction.c
@@ -673,16 +673,7 @@ do_get_write_access(handle_t *handle, struct journal_head *jh,
 				jbd_unlock_bh_state(bh);
 				frozen_buffer =
 					jbd_alloc(jh2bh(jh)->b_size,
-							 GFP_NOFS);
-				if (!frozen_buffer) {
-					printk(KERN_ERR
-					       "%s: OOM for frozen_buffer\n",
-					       __func__);
-					JBUFFER_TRACE(jh, "oom!");
-					error = -ENOMEM;
-					jbd_lock_bh_state(bh);
-					goto done;
-				}
+							 GFP_NOFS|__GFP_NOFAIL);
 				goto repeat;
 			}
 			jh->b_frozen_data = frozen_buffer;
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index ff2f2e6ad311..bff071e21553 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -923,16 +923,7 @@ do_get_write_access(handle_t *handle, struct journal_head *jh,
 				jbd_unlock_bh_state(bh);
 				frozen_buffer =
 					jbd2_alloc(jh2bh(jh)->b_size,
-							 GFP_NOFS);
-				if (!frozen_buffer) {
-					printk(KERN_ERR
-					       "%s: OOM for frozen_buffer\n",
-					       __func__);
-					JBUFFER_TRACE(jh, "oom!");
-					error = -ENOMEM;
-					jbd_lock_bh_state(bh);
-					goto done;
-				}
+							 GFP_NOFS|__GFP_NOFAIL);
 				goto repeat;
 			}
 			jh->b_frozen_data = frozen_buffer;
@@ -1157,7 +1148,8 @@ int jbd2_journal_get_undo_access(handle_t *handle, struct buffer_head *bh)
 
 repeat:
 	if (!jh->b_committed_data) {
-		committed_data = jbd2_alloc(jh2bh(jh)->b_size, GFP_NOFS);
+		committed_data = jbd2_alloc(jh2bh(jh)->b_size,
+					    GFP_NOFS|__GFP_NOFAIL);
 		if (!committed_data) {
 			printk(KERN_ERR "%s: No memory for committed data\n",
 				__func__);
-- 
2.5.0

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#1200661 — Re: [RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure

FromJan Kara <jack@suse.cz>
Date2015-08-05 13:50 +0200
SubjectRe: [RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure
Message-ID<pU5mN-bE-5@gated-at.bofh.it>
In reply to#1200600
On Wed 05-08-15 11:51:20, mhocko@kernel.org wrote:
> From: Michal Hocko <mhocko@suse.com>
> 
> Journal transaction might fail prematurely because the frozen_buffer
> is allocated by GFP_NOFS request:
> [   72.440013] do_get_write_access: OOM for frozen_buffer
> [   72.440014] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
> [   72.440015] EXT4-fs error (device sda1) in ext4_reserve_inode_write:4735: Out of memory
> (...snipped....)
> [   72.495559] do_get_write_access: OOM for frozen_buffer
> [   72.495560] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
> [   72.496839] do_get_write_access: OOM for frozen_buffer
> [   72.496841] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
> [   72.505766] Aborting journal on device sda1-8.
> [   72.505851] EXT4-fs (sda1): Remounting filesystem read-only
> 
> This wasn't a problem until "mm: page_alloc: do not lock up GFP_NOFS
> allocations upon OOM" because small GPF_NOFS allocations never failed.
> This allocation seems essential for the journal and GFP_NOFS is too
> restrictive to the memory allocator so let's use __GFP_NOFAIL here to
> emulate the previous behavior.
> 
> jbd code has the very same issue so let's do the same there as well.

The patch looks good. Btw, the patch 6 can be folded into this patch since
it fixes the issue you fix for jbd2 here... But jbd parts will be dropped
in the next merge window anyway so it doesn't really matter.

You can add:

Reviewed-by: Jan Kara <jack@suse.com>

								Honza
> 
> Signed-off-by: Michal Hocko <mhocko@suse.com>
> ---
>  fs/jbd/transaction.c  | 11 +----------
>  fs/jbd2/transaction.c | 14 +++-----------
>  2 files changed, 4 insertions(+), 21 deletions(-)
> 
> diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
> index 1695ba8334a2..bf7474deda2f 100644
> --- a/fs/jbd/transaction.c
> +++ b/fs/jbd/transaction.c
> @@ -673,16 +673,7 @@ do_get_write_access(handle_t *handle, struct journal_head *jh,
>  				jbd_unlock_bh_state(bh);
>  				frozen_buffer =
>  					jbd_alloc(jh2bh(jh)->b_size,
> -							 GFP_NOFS);
> -				if (!frozen_buffer) {
> -					printk(KERN_ERR
> -					       "%s: OOM for frozen_buffer\n",
> -					       __func__);
> -					JBUFFER_TRACE(jh, "oom!");
> -					error = -ENOMEM;
> -					jbd_lock_bh_state(bh);
> -					goto done;
> -				}
> +							 GFP_NOFS|__GFP_NOFAIL);
>  				goto repeat;
>  			}
>  			jh->b_frozen_data = frozen_buffer;
> diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
> index ff2f2e6ad311..bff071e21553 100644
> --- a/fs/jbd2/transaction.c
> +++ b/fs/jbd2/transaction.c
> @@ -923,16 +923,7 @@ do_get_write_access(handle_t *handle, struct journal_head *jh,
>  				jbd_unlock_bh_state(bh);
>  				frozen_buffer =
>  					jbd2_alloc(jh2bh(jh)->b_size,
> -							 GFP_NOFS);
> -				if (!frozen_buffer) {
> -					printk(KERN_ERR
> -					       "%s: OOM for frozen_buffer\n",
> -					       __func__);
> -					JBUFFER_TRACE(jh, "oom!");
> -					error = -ENOMEM;
> -					jbd_lock_bh_state(bh);
> -					goto done;
> -				}
> +							 GFP_NOFS|__GFP_NOFAIL);
>  				goto repeat;
>  			}
>  			jh->b_frozen_data = frozen_buffer;
> @@ -1157,7 +1148,8 @@ int jbd2_journal_get_undo_access(handle_t *handle, struct buffer_head *bh)
>  
>  repeat:
>  	if (!jh->b_committed_data) {
> -		committed_data = jbd2_alloc(jh2bh(jh)->b_size, GFP_NOFS);
> +		committed_data = jbd2_alloc(jh2bh(jh)->b_size,
> +					    GFP_NOFS|__GFP_NOFAIL);
>  		if (!committed_data) {
>  			printk(KERN_ERR "%s: No memory for committed data\n",
>  				__func__);
> -- 
> 2.5.0
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR
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#1200986

FromGreg Thelen <gthelen@google.com>
Date2015-08-05 18:50 +0200
Message-ID<pUa38-72o-27@gated-at.bofh.it>
In reply to#1200600
mhocko@kernel.org wrote:

> From: Michal Hocko <mhocko@suse.com>
>
> Journal transaction might fail prematurely because the frozen_buffer
> is allocated by GFP_NOFS request:
> [   72.440013] do_get_write_access: OOM for frozen_buffer
> [   72.440014] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
> [   72.440015] EXT4-fs error (device sda1) in ext4_reserve_inode_write:4735: Out of memory
> (...snipped....)
> [   72.495559] do_get_write_access: OOM for frozen_buffer
> [   72.495560] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
> [   72.496839] do_get_write_access: OOM for frozen_buffer
> [   72.496841] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
> [   72.505766] Aborting journal on device sda1-8.
> [   72.505851] EXT4-fs (sda1): Remounting filesystem read-only
>
> This wasn't a problem until "mm: page_alloc: do not lock up GFP_NOFS
> allocations upon OOM" because small GPF_NOFS allocations never failed.
> This allocation seems essential for the journal and GFP_NOFS is too
> restrictive to the memory allocator so let's use __GFP_NOFAIL here to
> emulate the previous behavior.
>
> jbd code has the very same issue so let's do the same there as well.
>
> Signed-off-by: Michal Hocko <mhocko@suse.com>
> ---
>  fs/jbd/transaction.c  | 11 +----------
>  fs/jbd2/transaction.c | 14 +++-----------
>  2 files changed, 4 insertions(+), 21 deletions(-)
>
> diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
> index 1695ba8334a2..bf7474deda2f 100644
> --- a/fs/jbd/transaction.c
> +++ b/fs/jbd/transaction.c
> @@ -673,16 +673,7 @@ do_get_write_access(handle_t *handle, struct journal_head *jh,
>  				jbd_unlock_bh_state(bh);
>  				frozen_buffer =
>  					jbd_alloc(jh2bh(jh)->b_size,
> -							 GFP_NOFS);
> -				if (!frozen_buffer) {
> -					printk(KERN_ERR
> -					       "%s: OOM for frozen_buffer\n",
> -					       __func__);
> -					JBUFFER_TRACE(jh, "oom!");
> -					error = -ENOMEM;
> -					jbd_lock_bh_state(bh);
> -					goto done;
> -				}
> +							 GFP_NOFS|__GFP_NOFAIL);
>  				goto repeat;
>  			}
>  			jh->b_frozen_data = frozen_buffer;
> diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
> index ff2f2e6ad311..bff071e21553 100644
> --- a/fs/jbd2/transaction.c
> +++ b/fs/jbd2/transaction.c
> @@ -923,16 +923,7 @@ do_get_write_access(handle_t *handle, struct journal_head *jh,
>  				jbd_unlock_bh_state(bh);
>  				frozen_buffer =
>  					jbd2_alloc(jh2bh(jh)->b_size,
> -							 GFP_NOFS);
> -				if (!frozen_buffer) {
> -					printk(KERN_ERR
> -					       "%s: OOM for frozen_buffer\n",
> -					       __func__);
> -					JBUFFER_TRACE(jh, "oom!");
> -					error = -ENOMEM;
> -					jbd_lock_bh_state(bh);
> -					goto done;
> -				}
> +							 GFP_NOFS|__GFP_NOFAIL);
>  				goto repeat;
>  			}
>  			jh->b_frozen_data = frozen_buffer;
> @@ -1157,7 +1148,8 @@ int jbd2_journal_get_undo_access(handle_t *handle, struct buffer_head *bh)
>  
>  repeat:
>  	if (!jh->b_committed_data) {
> -		committed_data = jbd2_alloc(jh2bh(jh)->b_size, GFP_NOFS);
> +		committed_data = jbd2_alloc(jh2bh(jh)->b_size,
> +					    GFP_NOFS|__GFP_NOFAIL);
>  		if (!committed_data) {
>  			printk(KERN_ERR "%s: No memory for committed data\n",
>  				__func__);

Is this "if (!committed_data) {" check now dead code?

I also see other similar suspected dead sites in the rest of the series.
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#1205774 — Re: [RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure

FromMichal Hocko <mhocko@kernel.org>
Date2015-08-12 11:20 +0200
SubjectRe: [RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure
Message-ID<pWAmx-8tE-71@gated-at.bofh.it>
In reply to#1200986
On Wed 05-08-15 09:49:24, Greg Thelen wrote:
> 
> mhocko@kernel.org wrote:
> 
> > From: Michal Hocko <mhocko@suse.com>
> >
> > Journal transaction might fail prematurely because the frozen_buffer
> > is allocated by GFP_NOFS request:
> > [   72.440013] do_get_write_access: OOM for frozen_buffer
> > [   72.440014] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
> > [   72.440015] EXT4-fs error (device sda1) in ext4_reserve_inode_write:4735: Out of memory
> > (...snipped....)
> > [   72.495559] do_get_write_access: OOM for frozen_buffer
> > [   72.495560] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
> > [   72.496839] do_get_write_access: OOM for frozen_buffer
> > [   72.496841] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
> > [   72.505766] Aborting journal on device sda1-8.
> > [   72.505851] EXT4-fs (sda1): Remounting filesystem read-only
> >
> > This wasn't a problem until "mm: page_alloc: do not lock up GFP_NOFS
> > allocations upon OOM" because small GPF_NOFS allocations never failed.
> > This allocation seems essential for the journal and GFP_NOFS is too
> > restrictive to the memory allocator so let's use __GFP_NOFAIL here to
> > emulate the previous behavior.
> >
> > jbd code has the very same issue so let's do the same there as well.
> >
> > Signed-off-by: Michal Hocko <mhocko@suse.com>
> > ---
> >  fs/jbd/transaction.c  | 11 +----------
> >  fs/jbd2/transaction.c | 14 +++-----------
> >  2 files changed, 4 insertions(+), 21 deletions(-)
> >
> > diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
> > index 1695ba8334a2..bf7474deda2f 100644
> > --- a/fs/jbd/transaction.c
> > +++ b/fs/jbd/transaction.c
> > @@ -673,16 +673,7 @@ do_get_write_access(handle_t *handle, struct journal_head *jh,
> >  				jbd_unlock_bh_state(bh);
> >  				frozen_buffer =
> >  					jbd_alloc(jh2bh(jh)->b_size,
> > -							 GFP_NOFS);
> > -				if (!frozen_buffer) {
> > -					printk(KERN_ERR
> > -					       "%s: OOM for frozen_buffer\n",
> > -					       __func__);
> > -					JBUFFER_TRACE(jh, "oom!");
> > -					error = -ENOMEM;
> > -					jbd_lock_bh_state(bh);
> > -					goto done;
> > -				}
> > +							 GFP_NOFS|__GFP_NOFAIL);
> >  				goto repeat;
> >  			}
> >  			jh->b_frozen_data = frozen_buffer;
> > diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
> > index ff2f2e6ad311..bff071e21553 100644
> > --- a/fs/jbd2/transaction.c
> > +++ b/fs/jbd2/transaction.c
> > @@ -923,16 +923,7 @@ do_get_write_access(handle_t *handle, struct journal_head *jh,
> >  				jbd_unlock_bh_state(bh);
> >  				frozen_buffer =
> >  					jbd2_alloc(jh2bh(jh)->b_size,
> > -							 GFP_NOFS);
> > -				if (!frozen_buffer) {
> > -					printk(KERN_ERR
> > -					       "%s: OOM for frozen_buffer\n",
> > -					       __func__);
> > -					JBUFFER_TRACE(jh, "oom!");
> > -					error = -ENOMEM;
> > -					jbd_lock_bh_state(bh);
> > -					goto done;
> > -				}
> > +							 GFP_NOFS|__GFP_NOFAIL);
> >  				goto repeat;
> >  			}
> >  			jh->b_frozen_data = frozen_buffer;
> > @@ -1157,7 +1148,8 @@ int jbd2_journal_get_undo_access(handle_t *handle, struct buffer_head *bh)
> >  
> >  repeat:
> >  	if (!jh->b_committed_data) {
> > -		committed_data = jbd2_alloc(jh2bh(jh)->b_size, GFP_NOFS);
> > +		committed_data = jbd2_alloc(jh2bh(jh)->b_size,
> > +					    GFP_NOFS|__GFP_NOFAIL);
> >  		if (!committed_data) {
> >  			printk(KERN_ERR "%s: No memory for committed data\n",
> >  				__func__);
> 
> Is this "if (!committed_data) {" check now dead code?
> 
> I also see other similar suspected dead sites in the rest of the series.

You are absolutely right. I have updated the patches.

Thanks!
-- 
Michal Hocko
SUSE Labs
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#1208089 — Re: [RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure

FromTheodore Ts'o <tytso@mit.edu>
Date2015-08-15 16:00 +0200
SubjectRe: [RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure
Message-ID<pXKa5-3ff-9@gated-at.bofh.it>
In reply to#1205774
On Wed, Aug 12, 2015 at 11:14:11AM +0200, Michal Hocko wrote:
> > Is this "if (!committed_data) {" check now dead code?
> > 
> > I also see other similar suspected dead sites in the rest of the series.
> 
> You are absolutely right. I have updated the patches.

Have you sent out an updated version of these patches?  Maybe I missed
it, but I don't think I saw them.

Thanks,

						- Ted
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#1209169 — Re: [RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure

FromMichal Hocko <mhocko@kernel.org>
Date2015-08-18 12:40 +0200
SubjectRe: [RFC 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure
Message-ID<pYMtc-3yQ-19@gated-at.bofh.it>
In reply to#1208089
On Sat 15-08-15 09:54:22, Theodore Ts'o wrote:
> On Wed, Aug 12, 2015 at 11:14:11AM +0200, Michal Hocko wrote:
> > > Is this "if (!committed_data) {" check now dead code?
> > > 
> > > I also see other similar suspected dead sites in the rest of the series.
> > 
> > You are absolutely right. I have updated the patches.
> 
> Have you sent out an updated version of these patches?  Maybe I missed
> it, but I don't think I saw them.

I haven't yet. I was waiting for more feedback and didn't want to spam
the mailing list too much. I will post them now.
-- 
Michal Hocko
SUSE Labs
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#1209173 — [RFC -v2 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure

FromMichal Hocko <mhocko@kernel.org>
Date2015-08-18 12:40 +0200
Subject[RFC -v2 4/8] jbd, jbd2: Do not fail journal because of frozen_buffer allocation failure
Message-ID<pYMtc-3yQ-23@gated-at.bofh.it>
In reply to#1200600
From: Michal Hocko <mhocko@suse.com>

Journal transaction might fail prematurely because the frozen_buffer
is allocated by GFP_NOFS request:
[   72.440013] do_get_write_access: OOM for frozen_buffer
[   72.440014] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
[   72.440015] EXT4-fs error (device sda1) in ext4_reserve_inode_write:4735: Out of memory
(...snipped....)
[   72.495559] do_get_write_access: OOM for frozen_buffer
[   72.495560] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
[   72.496839] do_get_write_access: OOM for frozen_buffer
[   72.496841] EXT4-fs: ext4_reserve_inode_write:4729: aborting transaction: Out of memory in __ext4_journal_get_write_access
[   72.505766] Aborting journal on device sda1-8.
[   72.505851] EXT4-fs (sda1): Remounting filesystem read-only

This wasn't a problem until "mm: page_alloc: do not lock up GFP_NOFS
allocations upon OOM" because small GPF_NOFS allocations never failed.
This allocation seems essential for the journal and GFP_NOFS is too
restrictive to the memory allocator so let's use __GFP_NOFAIL here to
emulate the previous behavior.

jbd code has the very same issue so let's do the same there as well.

Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 fs/jbd/transaction.c  | 11 +----------
 fs/jbd2/transaction.c | 23 ++++-------------------
 2 files changed, 5 insertions(+), 29 deletions(-)

diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
index 1695ba8334a2..bf7474deda2f 100644
--- a/fs/jbd/transaction.c
+++ b/fs/jbd/transaction.c
@@ -673,16 +673,7 @@ do_get_write_access(handle_t *handle, struct journal_head *jh,
 				jbd_unlock_bh_state(bh);
 				frozen_buffer =
 					jbd_alloc(jh2bh(jh)->b_size,
-							 GFP_NOFS);
-				if (!frozen_buffer) {
-					printk(KERN_ERR
-					       "%s: OOM for frozen_buffer\n",
-					       __func__);
-					JBUFFER_TRACE(jh, "oom!");
-					error = -ENOMEM;
-					jbd_lock_bh_state(bh);
-					goto done;
-				}
+							 GFP_NOFS|__GFP_NOFAIL);
 				goto repeat;
 			}
 			jh->b_frozen_data = frozen_buffer;
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index ff2f2e6ad311..4d63c5911afa 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -923,16 +923,7 @@ do_get_write_access(handle_t *handle, struct journal_head *jh,
 				jbd_unlock_bh_state(bh);
 				frozen_buffer =
 					jbd2_alloc(jh2bh(jh)->b_size,
-							 GFP_NOFS);
-				if (!frozen_buffer) {
-					printk(KERN_ERR
-					       "%s: OOM for frozen_buffer\n",
-					       __func__);
-					JBUFFER_TRACE(jh, "oom!");
-					error = -ENOMEM;
-					jbd_lock_bh_state(bh);
-					goto done;
-				}
+							 GFP_NOFS|__GFP_NOFAIL);
 				goto repeat;
 			}
 			jh->b_frozen_data = frozen_buffer;
@@ -1156,15 +1147,9 @@ int jbd2_journal_get_undo_access(handle_t *handle, struct buffer_head *bh)
 		goto out;
 
 repeat:
-	if (!jh->b_committed_data) {
-		committed_data = jbd2_alloc(jh2bh(jh)->b_size, GFP_NOFS);
-		if (!committed_data) {
-			printk(KERN_ERR "%s: No memory for committed data\n",
-				__func__);
-			err = -ENOMEM;
-			goto out;
-		}
-	}
+	if (!jh->b_committed_data)
+		committed_data = jbd2_alloc(jh2bh(jh)->b_size,
+					    GFP_NOFS|__GFP_NOFAIL);
 
 	jbd_lock_bh_state(bh);
 	if (!jh->b_committed_data) {
-- 
2.5.0

-- 
Michal Hocko
SUSE Labs
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