On current git head webservers stopped working

On current git head webservers stopped working

[Gabriel C]

Hello ,

While doing some tests with 2.6.22-git2 ( at the time head
4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4 ) all my webservers stopped
working.
I can't get any file using wget or whatever else , everything hangs
after 1% forever.

I bisected this and here the result:

534f2aaa6ab07cd71164180bc958a7dcde41db11 is first bad commit
commit 534f2aaa6ab07cd71164180bc958a7dcde41db11
Author: Jens Axboe <jens.axboe@oracle.com>
Date:   Fri Jun 1 14:52:37 2007 +0200

    sys_sendfile: switch to using ->splice_read, if available

    This patch makes sendfile prefer to use ->splice_read(), if it's
    available in the file_operations structure.

    Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

:040000 040000 b19013793692eee0f632b3703dca0bd40cea753f
ed50576c0d3f0d3ce9f1a2ac9336d1164b45f63f M      fs


This is :

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blobdiff;f=fs/read_write.c;h=47da8a4a0fbecd1bbf00aaf29fd1fdc6dc7408d8;hp=4d03008f015b9ae6d2565cdbc179d034687c3d08;hb=534f2aaa6ab07cd71164180bc958a7dcde41db11;hpb=6a14b90bb6bc7cd83e2a444bf457a2ea645cbfe7

crazy@lara:/work/crazy/linux-git/linux-2.6$ git bisect log
git-bisect start
# bad: [4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4] lots-of-architectures:
enable arbitary speed tty support
git-bisect bad 4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4
# good: [7dcca30a32aadb0520417521b0c44f42d09fe05c] Linux 2.6.22
git-bisect good 7dcca30a32aadb0520417521b0c44f42d09fe05c
# good: [bf74b964775009071cf12f9d59d4dd5e388fbe0b] [MIPS] DEC: Fix
modpost warning.
git-bisect good bf74b964775009071cf12f9d59d4dd5e388fbe0b
# bad: [1b21f458ddbc8fb6fceeb68158e9e04b2571dabd] Merge
git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw
git-bisect bad 1b21f458ddbc8fb6fceeb68158e9e04b2571dabd
# bad: [01370f0603f8435d415a19f7e62d1bab826c3589] Merge branch
'splice-2.6.23' of git://git.kernel.dk/data/git/linux-2.6-block
git-bisect bad 01370f0603f8435d415a19f7e62d1bab826c3589
# good: [4f179f71607382888c5ce5385a4ee136e1a2002a] Input: serio_raw -
shut up errorneous warning
git-bisect good 4f179f71607382888c5ce5385a4ee136e1a2002a
# bad: [cac36bb06efe4880234524e117e0e712b10b1f16] pipe: change the
->pin() operation to ->confirm()
git-bisect bad cac36bb06efe4880234524e117e0e712b10b1f16
# bad: [cf8208d0eabd1d5d2625ec02a175a294c3f30d36] sendfile: convert nfsd
to splice_direct_to_actor()
git-bisect bad cf8208d0eabd1d5d2625ec02a175a294c3f30d36
# bad: [5ffc4ef45b3b0a57872f631b4e4ceb8ace0d7496] sendfile: remove
.sendfile from filesystems that use generic_file_sendfile()
git-bisect bad 5ffc4ef45b3b0a57872f631b4e4ceb8ace0d7496
# good: [6a14b90bb6bc7cd83e2a444bf457a2ea645cbfe7] vmsplice: add
vmsplice-to-user support
git-bisect good 6a14b90bb6bc7cd83e2a444bf457a2ea645cbfe7
# bad: [534f2aaa6ab07cd71164180bc958a7dcde41db11] sys_sendfile: switch
to using ->splice_read, if available
git-bisect bad 534f2aaa6ab07cd71164180bc958a7dcde41db11


Reverting 534f2aaa6ab07cd71164180bc958a7dcde41db11 from git2 solved that
problem for me.

I've compiled current git head and the problem still exists but I cannot
revert this commit while some conflicts.



Regards ,

Gabriel C

Re: On current git head webservers stopped working

[Jens Axboe]

On Fri, Jul 13 2007, Gabriel C wrote:
> Hello ,
> 
> While doing some tests with 2.6.22-git2 ( at the time head
> 4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4 ) all my webservers stopped
> working.
> I can't get any file using wget or whatever else , everything hangs
> after 1% forever.
> 
> I bisected this and here the result:
> 
> 534f2aaa6ab07cd71164180bc958a7dcde41db11 is first bad commit
> commit 534f2aaa6ab07cd71164180bc958a7dcde41db11
> Author: Jens Axboe <jens.axboe@oracle.com>
> Date:   Fri Jun 1 14:52:37 2007 +0200
> 
>     sys_sendfile: switch to using ->splice_read, if available
> 
>     This patch makes sendfile prefer to use ->splice_read(), if it's
>     available in the file_operations structure.
> 
>     Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
> 
> :040000 040000 b19013793692eee0f632b3703dca0bd40cea753f
> ed50576c0d3f0d3ce9f1a2ac9336d1164b45f63f M      fs

Does this work?

diff --git a/fs/splice.c b/fs/splice.c
index ed2ce99..92646aa 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -491,7 +491,7 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
 
 	ret = 0;
 	spliced = 0;
-	while (len) {
+	while (len && !spliced) {
 		ret = __generic_file_splice_read(in, ppos, pipe, len, flags);
 
 		if (ret < 0)
@@ -1051,15 +1051,10 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
 	sd->flags &= ~SPLICE_F_NONBLOCK;
 
 	while (len) {
-		size_t read_len, max_read_len;
-
-		/*
-		 * Do at most PIPE_BUFFERS pages worth of transfer:
-		 */
-		max_read_len = min(len, (size_t)(PIPE_BUFFERS*PAGE_SIZE));
+		size_t read_len;
 
-		ret = do_splice_to(in, &sd->pos, pipe, max_read_len, flags);
-		if (unlikely(ret < 0))
+		ret = do_splice_to(in, &sd->pos, pipe, len, flags);
+		if (unlikely(ret <= 0))
 			goto out_release;
 
 		read_len = ret;
@@ -1071,26 +1066,17 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
 		 * could get stuck data in the internal pipe:
 		 */
 		ret = actor(pipe, sd);
-		if (unlikely(ret < 0))
+		if (unlikely(ret <= 0))
 			goto out_release;
 
 		bytes += ret;
 		len -= ret;
 
-		/*
-		 * In nonblocking mode, if we got back a short read then
-		 * that was due to either an IO error or due to the
-		 * pagecache entry not being there. In the IO error case
-		 * the _next_ splice attempt will produce a clean IO error
-		 * return value (not a short read), so in both cases it's
-		 * correct to break out of the loop here:
-		 */
-		if ((flags & SPLICE_F_NONBLOCK) && (read_len < max_read_len))
-			break;
+		if (ret < read_len)
+			goto out_release;
 	}
 
 	pipe->nrbufs = pipe->curbuf = 0;
-
 	return bytes;
 
 out_release:
@@ -1152,10 +1138,12 @@ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
 		.pos		= *ppos,
 		.u.file		= out,
 	};
-	size_t ret;
+	long ret;
 
 	ret = splice_direct_to_actor(in, &sd, direct_splice_actor);
-	*ppos = sd.pos;
+	if (ret > 0)
+		*ppos += ret;
+
 	return ret;
 }
 

-- 
Jens Axboe

Re: On current git head webservers stopped working

[Gabriel C]

Jens Axboe wrote:
> On Fri, Jul 13 2007, Gabriel C wrote:
>   
>> Hello ,
>>
>> While doing some tests with 2.6.22-git2 ( at the time head
>> 4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4 ) all my webservers stopped
>> working.
>> I can't get any file using wget or whatever else , everything hangs
>> after 1% forever.
>>
>> I bisected this and here the result:
>>
>> 534f2aaa6ab07cd71164180bc958a7dcde41db11 is first bad commit
>> commit 534f2aaa6ab07cd71164180bc958a7dcde41db11
>> Author: Jens Axboe <jens.axboe@oracle.com>
>> Date:   Fri Jun 1 14:52:37 2007 +0200
>>
>>     sys_sendfile: switch to using ->splice_read, if available
>>
>>     This patch makes sendfile prefer to use ->splice_read(), if it's
>>     available in the file_operations structure.
>>
>>     Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
>>
>> :040000 040000 b19013793692eee0f632b3703dca0bd40cea753f
>> ed50576c0d3f0d3ce9f1a2ac9336d1164b45f63f M      fs
>>     
>
> Does this work?
>   

Yes , it does. Thx :)

> diff --git a/fs/splice.c b/fs/splice.c
> index ed2ce99..92646aa 100644
> --- a/fs/splice.c
> +++ b/fs/splice.c
> @@ -491,7 +491,7 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
>  
>  	ret = 0;
>  	spliced = 0;
> -	while (len) {
> +	while (len && !spliced) {
>  		ret = __generic_file_splice_read(in, ppos, pipe, len, flags);
>  
>  		if (ret < 0)
> @@ -1051,15 +1051,10 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
>  	sd->flags &= ~SPLICE_F_NONBLOCK;
>  
>  	while (len) {
> -		size_t read_len, max_read_len;
> -
> -		/*
> -		 * Do at most PIPE_BUFFERS pages worth of transfer:
> -		 */
> -		max_read_len = min(len, (size_t)(PIPE_BUFFERS*PAGE_SIZE));
> +		size_t read_len;
>  
> -		ret = do_splice_to(in, &sd->pos, pipe, max_read_len, flags);
> -		if (unlikely(ret < 0))
> +		ret = do_splice_to(in, &sd->pos, pipe, len, flags);
> +		if (unlikely(ret <= 0))
>  			goto out_release;
>  
>  		read_len = ret;
> @@ -1071,26 +1066,17 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
>  		 * could get stuck data in the internal pipe:
>  		 */
>  		ret = actor(pipe, sd);
> -		if (unlikely(ret < 0))
> +		if (unlikely(ret <= 0))
>  			goto out_release;
>  
>  		bytes += ret;
>  		len -= ret;
>  
> -		/*
> -		 * In nonblocking mode, if we got back a short read then
> -		 * that was due to either an IO error or due to the
> -		 * pagecache entry not being there. In the IO error case
> -		 * the _next_ splice attempt will produce a clean IO error
> -		 * return value (not a short read), so in both cases it's
> -		 * correct to break out of the loop here:
> -		 */
> -		if ((flags & SPLICE_F_NONBLOCK) && (read_len < max_read_len))
> -			break;
> +		if (ret < read_len)
> +			goto out_release;
>  	}
>  
>  	pipe->nrbufs = pipe->curbuf = 0;
> -
>  	return bytes;
>  
>  out_release:
> @@ -1152,10 +1138,12 @@ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
>  		.pos		= *ppos,
>  		.u.file		= out,
>  	};
> -	size_t ret;
> +	long ret;
>  
>  	ret = splice_direct_to_actor(in, &sd, direct_splice_actor);
> -	*ppos = sd.pos;
> +	if (ret > 0)
> +		*ppos += ret;
> +
>  	return ret;
>  }
>  
>
>   

Re: On current git head webservers stopped working

[Jens Axboe]

On Fri, Jul 13 2007, Gabriel C wrote:
> Jens Axboe wrote:
> > On Fri, Jul 13 2007, Gabriel C wrote:
> >   
> >> Hello ,
> >>
> >> While doing some tests with 2.6.22-git2 ( at the time head
> >> 4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4 ) all my webservers stopped
> >> working.
> >> I can't get any file using wget or whatever else , everything hangs
> >> after 1% forever.
> >>
> >> I bisected this and here the result:
> >>
> >> 534f2aaa6ab07cd71164180bc958a7dcde41db11 is first bad commit
> >> commit 534f2aaa6ab07cd71164180bc958a7dcde41db11
> >> Author: Jens Axboe <jens.axboe@oracle.com>
> >> Date:   Fri Jun 1 14:52:37 2007 +0200
> >>
> >>     sys_sendfile: switch to using ->splice_read, if available
> >>
> >>     This patch makes sendfile prefer to use ->splice_read(), if it's
> >>     available in the file_operations structure.
> >>
> >>     Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
> >>
> >> :040000 040000 b19013793692eee0f632b3703dca0bd40cea753f
> >> ed50576c0d3f0d3ce9f1a2ac9336d1164b45f63f M      fs
> >>     
> >
> > Does this work?
> >   
> 
> Yes , it does. Thx :)

Great, I'll polish it a bit and get it upstream asap. Thanks for the
report and quick test feedback!

-- 
Jens Axboe

Re: On current git head webservers stopped working

[Christoph Hellwig]

On Fri, Jul 13, 2007 at 12:00:58PM +0200, Jens Axboe wrote:
> On Fri, Jul 13 2007, Gabriel C wrote:
> > Jens Axboe wrote:
> > > On Fri, Jul 13 2007, Gabriel C wrote:
> > >   
> > >> Hello ,
> > >>
> > >> While doing some tests with 2.6.22-git2 ( at the time head
> > >> 4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4 ) all my webservers stopped
> > >> working.
> > >> I can't get any file using wget or whatever else , everything hangs
> > >> after 1% forever.
> > >>
> > >> I bisected this and here the result:
> > >>
> > >> 534f2aaa6ab07cd71164180bc958a7dcde41db11 is first bad commit
> > >> commit 534f2aaa6ab07cd71164180bc958a7dcde41db11
> > >> Author: Jens Axboe <jens.axboe@oracle.com>
> > >> Date:   Fri Jun 1 14:52:37 2007 +0200
> > >>
> > >>     sys_sendfile: switch to using ->splice_read, if available
> > >>
> > >>     This patch makes sendfile prefer to use ->splice_read(), if it's
> > >>     available in the file_operations structure.
> > >>
> > >>     Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
> > >>
> > >> :040000 040000 b19013793692eee0f632b3703dca0bd40cea753f
> > >> ed50576c0d3f0d3ce9f1a2ac9336d1164b45f63f M      fs
> > >>     
> > >
> > > Does this work?
> > >   
> > 
> > Yes , it does. Thx :)
> 
> Great, I'll polish it a bit and get it upstream asap. Thanks for the
> report and quick test feedback!

Any chance someone could hack up a ltp testcase for this?

Re: On current git head webservers stopped working

[Gabriel C]

Jens Axboe wrote:
> On Fri, Jul 13 2007, Gabriel C wrote:
>   
>> Jens Axboe wrote:
>>     
>>> On Fri, Jul 13 2007, Gabriel C wrote:
>>>   
>>>       
>>>> Hello ,
>>>>
>>>> While doing some tests with 2.6.22-git2 ( at the time head
>>>> 4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4 ) all my webservers stopped
>>>> working.
>>>> I can't get any file using wget or whatever else , everything hangs
>>>> after 1% forever.
>>>>
>>>> I bisected this and here the result:
>>>>
>>>> 534f2aaa6ab07cd71164180bc958a7dcde41db11 is first bad commit
>>>> commit 534f2aaa6ab07cd71164180bc958a7dcde41db11
>>>> Author: Jens Axboe <jens.axboe@oracle.com>
>>>> Date:   Fri Jun 1 14:52:37 2007 +0200
>>>>
>>>>     sys_sendfile: switch to using ->splice_read, if available
>>>>
>>>>     This patch makes sendfile prefer to use ->splice_read(), if it's
>>>>     available in the file_operations structure.
>>>>
>>>>     Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
>>>>
>>>> :040000 040000 b19013793692eee0f632b3703dca0bd40cea753f
>>>> ed50576c0d3f0d3ce9f1a2ac9336d1164b45f63f M      fs
>>>>     
>>>>         
>>> Does this work?
>>>   
>>>       
>> Yes , it does. Thx :)
>>     
>
> Great, I'll polish it a bit and get it upstream asap. Thanks for the
> report and quick test feedback!
>
>   

You are welcome :)

If you want me to test the final version of this patch before you push
it upstream just ping me.

Re: On current git head webservers stopped working

[Jens Axboe]

On Fri, Jul 13 2007, Christoph Hellwig wrote:
> On Fri, Jul 13, 2007 at 12:00:58PM +0200, Jens Axboe wrote:
> > On Fri, Jul 13 2007, Gabriel C wrote:
> > > Jens Axboe wrote:
> > > > On Fri, Jul 13 2007, Gabriel C wrote:
> > > >   
> > > >> Hello ,
> > > >>
> > > >> While doing some tests with 2.6.22-git2 ( at the time head
> > > >> 4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4 ) all my webservers stopped
> > > >> working.
> > > >> I can't get any file using wget or whatever else , everything hangs
> > > >> after 1% forever.
> > > >>
> > > >> I bisected this and here the result:
> > > >>
> > > >> 534f2aaa6ab07cd71164180bc958a7dcde41db11 is first bad commit
> > > >> commit 534f2aaa6ab07cd71164180bc958a7dcde41db11
> > > >> Author: Jens Axboe <jens.axboe@oracle.com>
> > > >> Date:   Fri Jun 1 14:52:37 2007 +0200
> > > >>
> > > >>     sys_sendfile: switch to using ->splice_read, if available
> > > >>
> > > >>     This patch makes sendfile prefer to use ->splice_read(), if it's
> > > >>     available in the file_operations structure.
> > > >>
> > > >>     Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
> > > >>
> > > >> :040000 040000 b19013793692eee0f632b3703dca0bd40cea753f
> > > >> ed50576c0d3f0d3ce9f1a2ac9336d1164b45f63f M      fs
> > > >>     
> > > >
> > > > Does this work?
> > > >   
> > > 
> > > Yes , it does. Thx :)
> > 
> > Great, I'll polish it a bit and get it upstream asap. Thanks for the
> > report and quick test feedback!
> 
> Any chance someone could hack up a ltp testcase for this?

Certainly, I already created a private test case for it anyway.

-- 
Jens Axboe

Re: On current git head webservers stopped working

[Jens Axboe]

On Fri, Jul 13 2007, Gabriel C wrote:
> Jens Axboe wrote:
> > On Fri, Jul 13 2007, Gabriel C wrote:
> >   
> >> Jens Axboe wrote:
> >>     
> >>> On Fri, Jul 13 2007, Gabriel C wrote:
> >>>   
> >>>       
> >>>> Hello ,
> >>>>
> >>>> While doing some tests with 2.6.22-git2 ( at the time head
> >>>> 4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4 ) all my webservers stopped
> >>>> working.
> >>>> I can't get any file using wget or whatever else , everything hangs
> >>>> after 1% forever.
> >>>>
> >>>> I bisected this and here the result:
> >>>>
> >>>> 534f2aaa6ab07cd71164180bc958a7dcde41db11 is first bad commit
> >>>> commit 534f2aaa6ab07cd71164180bc958a7dcde41db11
> >>>> Author: Jens Axboe <jens.axboe@oracle.com>
> >>>> Date:   Fri Jun 1 14:52:37 2007 +0200
> >>>>
> >>>>     sys_sendfile: switch to using ->splice_read, if available
> >>>>
> >>>>     This patch makes sendfile prefer to use ->splice_read(), if it's
> >>>>     available in the file_operations structure.
> >>>>
> >>>>     Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
> >>>>
> >>>> :040000 040000 b19013793692eee0f632b3703dca0bd40cea753f
> >>>> ed50576c0d3f0d3ce9f1a2ac9336d1164b45f63f M      fs
> >>>>     
> >>>>         
> >>> Does this work?
> >>>   
> >>>       
> >> Yes , it does. Thx :)
> >>     
> >
> > Great, I'll polish it a bit and get it upstream asap. Thanks for the
> > report and quick test feedback!
> >
> >   
> 
> You are welcome :)
> 
> If you want me to test the final version of this patch before you push
> it upstream just ping me.

Thanks, I wrote a small test case though, so hopefully I'll be ok from
now though.

-- 
Jens Axboe

Re: On current git head webservers stopped working

[walt]

Jens Axboe wrote:
> On Fri, Jul 13 2007, Gabriel C wrote:
>> Hello ,
>>
>> While doing some tests with 2.6.22-git2 ( at the time head
>> 4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4 ) all my webservers stopped
>> working.
>> I can't get any file using wget or whatever else , everything hangs
>> after 1% forever.
>>
>> I bisected this and here the result:
>>
>> 534f2aaa6ab07cd71164180bc958a7dcde41db11 is first bad commit
>> commit 534f2aaa6ab07cd71164180bc958a7dcde41db11
>> Author: Jens Axboe <jens.axboe@oracle.com>
>> Date:   Fri Jun 1 14:52:37 2007 +0200
>>
>>     sys_sendfile: switch to using ->splice_read, if available
...

> Does this work?
<patch snipped>

Hi Jens,
I was hoping this patch would fix a different problem caused by the
same merge of 'splice-2.6.23' three days ago, but it didn't.

When I run nfsd on the latest git kernel, it serves up what seems to
be the wrong inodes for every fetched file.  I can navigate the served
directory structure with no problems, but the contents of any file I
fetch are completely unrelated to the real contents.

Does this suggest a possible cause or fix?

Thanks.

Re: On current git head webservers stopped working

[Linus Torvalds]

On Fri, 13 Jul 2007, Jens Axboe wrote:
> 
> Does this work?

Ok, so it apparently works, but:

> diff --git a/fs/splice.c b/fs/splice.c
> index ed2ce99..92646aa 100644
> --- a/fs/splice.c
> +++ b/fs/splice.c
> @@ -491,7 +491,7 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
>  
>  	ret = 0;
>  	spliced = 0;
> -	while (len) {
> +	while (len && !spliced) {
>  		ret = __generic_file_splice_read(in, ppos, pipe, len, flags);

This hunk basically make sthe whole "while" loop pointless. You'll never 
go through it more than once.

So at that point, maybe the loop should be removed entirely? Or maybe this 
part of the patch is wrong, and the fix was in the _other_ parts?

		Linus

Re: On current git head webservers stopped working

[Jens Axboe]

On Fri, Jul 13 2007, Linus Torvalds wrote:
> 
> 
> On Fri, 13 Jul 2007, Jens Axboe wrote:
> > 
> > Does this work?
> 
> Ok, so it apparently works, but:
> 
> > diff --git a/fs/splice.c b/fs/splice.c
> > index ed2ce99..92646aa 100644
> > --- a/fs/splice.c
> > +++ b/fs/splice.c
> > @@ -491,7 +491,7 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
> >  
> >  	ret = 0;
> >  	spliced = 0;
> > -	while (len) {
> > +	while (len && !spliced) {
> >  		ret = __generic_file_splice_read(in, ppos, pipe, len, flags);
> 
> This hunk basically make sthe whole "while" loop pointless. You'll never 
> go through it more than once.
> 
> So at that point, maybe the loop should be removed entirely? Or maybe this 
> part of the patch is wrong, and the fix was in the _other_ parts?

It'll likely work without that hunk, and you are right - the loop
should just go now. I'll update that piece in a sub sequent patch!

-- 
Jens Axboe

Re: On current git head webservers stopped working

[Jens Axboe]

On Fri, Jul 13 2007, Jens Axboe wrote:
> On Fri, Jul 13 2007, Linus Torvalds wrote:
> > 
> > 
> > On Fri, 13 Jul 2007, Jens Axboe wrote:
> > > 
> > > Does this work?
> > 
> > Ok, so it apparently works, but:
> > 
> > > diff --git a/fs/splice.c b/fs/splice.c
> > > index ed2ce99..92646aa 100644
> > > --- a/fs/splice.c
> > > +++ b/fs/splice.c
> > > @@ -491,7 +491,7 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
> > >  
> > >  	ret = 0;
> > >  	spliced = 0;
> > > -	while (len) {
> > > +	while (len && !spliced) {
> > >  		ret = __generic_file_splice_read(in, ppos, pipe, len, flags);
> > 
> > This hunk basically make sthe whole "while" loop pointless. You'll never 
> > go through it more than once.
> > 
> > So at that point, maybe the loop should be removed entirely? Or maybe this 
> > part of the patch is wrong, and the fix was in the _other_ parts?
> 
> It'll likely work without that hunk, and you are right - the loop
> should just go now. I'll update that piece in a sub sequent patch!

Oh btw, forgot to mention - that hunk isn't wrong, it's just not the fix
for that particular bug. In reality it should probably have been part of
a different patch dropping that loop as well... Anyway, I'll do that
patch and indicate as such in the changelog for that commit.

-- 
Jens Axboe