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From:   Steven French <Steven.French@microsoft.com>
To:     Nathan Chancellor <nathan@kernel.org>,
        ronnie sahlberg <ronniesahlberg@gmail.com>
CC:     kernel test robot <lkp@intel.com>,
        "llvm@lists.linux.dev" <llvm@lists.linux.dev>,
        "oe-kbuild-all@lists.linux.dev" <oe-kbuild-all@lists.linux.dev>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Shyam Prasad <Shyam.Prasad@microsoft.com>,
        "pc@manguebit.com" <pc@manguebit.com>
Subject: RE: [EXTERNAL] fs/smb/client/sess.c:160:5: warning: stack frame size
 (1152) exceeds limit (1024) in 'cifs_try_adding_channels'
Thread-Topic: [EXTERNAL] fs/smb/client/sess.c:160:5: warning: stack frame size
 (1152) exceeds limit (1024) in 'cifs_try_adding_channels'
Thread-Index: AQHZwBLWbILdzQpn2UWwGHu8Gccq46/M9bnQgADcHYCAAB4WIA==
Date:   Thu, 27 Jul 2023 18:32:11 +0000
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> There is probably more we can do on the compiler side to improve the spil=
ls but I suspect marking cifs_ses_add_channel() as noinline_for_stack or sw=
itching ctx to a head allocation would resolve this.

That makes sense - looks like the problem was introduced by putting a large=
 variable ctx (which is struct smb3_fs_context) on the stack in cifs_ses_ad=
d_channel() in sess.c line 363 for the patch referenced below

387ec58f339b0c45e3767395f11fa8dd3772131e cifs: simplify handling of cifs_sb=
/ctx->local_nls
(followed by "cifs: rename smb_vol as smb_fs_context and move it to fs_cont=
ext.h")

And could be fixed by malloc of ctx instead.   Probably not urgent and was =
only detected due to the directory move of these files from fs/cifs to fs/s=
mb/client so could do this for 6.6-rc


-----Original Message-----
From: Nathan Chancellor <nathan@kernel.org>
Sent: Thursday, July 27, 2023 11:40 AM
To: Steven French <Steven.French@microsoft.com>
Cc: kernel test robot <lkp@intel.com>; llvm@lists.linux.dev; oe-kbuild-all@=
lists.linux.dev; linux-kernel@vger.kernel.org
Subject: Re: [EXTERNAL] fs/smb/client/sess.c:160:5: warning: stack frame si=
ze (1152) exceeds limit (1024) in 'cifs_try_adding_channels'

[You don't often get email from nathan@kernel.org. Learn why this is import=
ant at https://aka.ms/LearnAboutSenderIdentification ]

Hi Steve,

On Thu, Jul 27, 2023 at 03:36:11AM +0000, Steven French wrote:
> Does anyone recognize the problem here - the stack size it is complaining=
 about has a small stack usage not a large one
>      cifs_try_adding_channels   has five pointers and five ints on the st=
ack.  That seems small - not large.  It is called by cifs_mount which doesn=
't seem too bad in its stack usage either.
>
> Any ideas why the stack size complaint is made?

Unfortunately, it seems like a recent-ish LLVM change removed the handy spi=
ll/variable information that would have shed a little more immediate light =
on this situation:

https://github.com/ClangBuiltLinux/linux/issues/1894

Building with a version that has that reveals:

  fs/smb/client/sess.c:160:5: warning: stack frame size (1152) exceeds limi=
t (1024) in 'cifs_try_adding_channels' [-Wframe-larger-than]
  int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, struct cifs_se=
s *ses)
      ^
  412/1152 (35.76%) spills, 740/1152 (64.24%) variables
  1 warning generated.

The spills are definitely not great but it looks like there is a moderately=
 large stack variable in cifs_ses_add_channel(), which gets inlined into ci=
fs_try_adding_channels(). Unfortunately, pahole appears to be borked for me=
 but -Rpass-analysis=3Dstack-frame-layout shows it:

  fs/smb/client/sess.c:161:1: remark:
  Function: cifs_try_adding_channels
  Offset: [SP-8], Type: Spill, Align: 8, Size: 8
  Offset: [SP-16], Type: Spill, Align: 8, Size: 8
  Offset: [SP-24], Type: Spill, Align: 8, Size: 8
  Offset: [SP-32], Type: Spill, Align: 8, Size: 8
  Offset: [SP-40], Type: Spill, Align: 8, Size: 8
  Offset: [SP-48], Type: Spill, Align: 8, Size: 8
  Offset: [SP-56], Type: Spill, Align: 8, Size: 8
  Offset: [SP-64], Type: Spill, Align: 8, Size: 8
  Offset: [SP-72], Type: Spill, Align: 8, Size: 8
  Offset: [SP-80], Type: Spill, Align: 8, Size: 8
  Offset: [SP-88], Type: Protector, Align: 8, Size: 8
  Offset: [SP-712], Type: Variable, Align: 8, Size: 624  <-- ctx, struct sm=
b3_fs_context
  Offset: [SP-801], Type: Variable, Align: 1, Size: 89
  Offset: [SP-816], Type: Spill, Align: 8, Size: 8
  Offset: [SP-824], Type: Spill, Align: 8, Size: 8
  Offset: [SP-832], Type: Spill, Align: 8, Size: 8
  Offset: [SP-840], Type: Spill, Align: 8, Size: 8
  Offset: [SP-848], Type: Spill, Align: 8, Size: 8
  Offset: [SP-856], Type: Spill, Align: 8, Size: 8
  Offset: [SP-864], Type: Spill, Align: 8, Size: 8
  Offset: [SP-872], Type: Spill, Align: 8, Size: 8
  Offset: [SP-880], Type: Spill, Align: 8, Size: 8
  Offset: [SP-888], Type: Spill, Align: 8, Size: 8
  Offset: [SP-896], Type: Spill, Align: 8, Size: 8
  Offset: [SP-904], Type: Spill, Align: 8, Size: 8
  Offset: [SP-912], Type: Spill, Align: 8, Size: 8
  Offset: [SP-920], Type: Spill, Align: 8, Size: 8
  Offset: [SP-928], Type: Spill, Align: 8, Size: 8
  Offset: [SP-936], Type: Spill, Align: 8, Size: 8
  Offset: [SP-944], Type: Spill, Align: 8, Size: 8
  Offset: [SP-952], Type: Spill, Align: 8, Size: 8
  Offset: [SP-960], Type: Spill, Align: 8, Size: 8
  Offset: [SP-968], Type: Spill, Align: 8, Size: 8
  Offset: [SP-976], Type: Spill, Align: 8, Size: 8
  Offset: [SP-984], Type: Spill, Align: 8, Size: 8
  Offset: [SP-992], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1000], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1008], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1016], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1024], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1028], Type: Spill, Align: 4, Size: 4
  Offset: [SP-1040], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1048], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1056], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1064], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1072], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1080], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1088], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1096], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1104], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1112], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1120], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1124], Type: Spill, Align: 4, Size: 4
  Offset: [SP-1128], Type: Spill, Align: 4, Size: 4
  Offset: [SP-1136], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1144], Type: Spill, Align: 8, Size: 8
  Offset: [SP-1152], Type: Spill, Align: 8, Size: 8 [-Rpass-analysis=3Dstac=
k-frame-layout]
    161 | {
        | ^

There is probably more we can do on the compiler side to improve the spills=
 but I suspect marking cifs_ses_add_channel() as noinline_for_stack or swit=
ching ctx to a head allocation would resolve this.

Cheers,
Nathan

> -----Original Message-----
> From: kernel test robot <lkp@intel.com>
> Sent: Wednesday, July 26, 2023 5:44 PM
> To: Steven French <Steven.French@microsoft.com>
> Cc: llvm@lists.linux.dev; oe-kbuild-all@lists.linux.dev;
> linux-kernel@vger.kernel.org
> Subject: [EXTERNAL] fs/smb/client/sess.c:160:5: warning: stack frame size=
 (1152) exceeds limit (1024) in 'cifs_try_adding_channels'
>
> Hi Steve,
>
> First bad commit (maybe !=3D root cause):
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.gi=
t master
> head:   0a8db05b571ad5b8d5c8774a004c0424260a90bd
> commit: 38c8a9a52082579090e34c033d439ed2cd1a462d smb: move client and ser=
ver files to common directory fs/smb
> date:   9 weeks ago
> config: mips-loongson2k_defconfig
> (https://dow/
> nload.01.org%2F0day-ci%2Farchive%2F20230727%2F202307270640.5ODmPwDl-lk
> p%40intel.com%2Fconfig&data=3D05%7C01%7CSteven.French%40microsoft.com%7C
> b15fd25d8a424332574308db8ec022d5%7C72f988bf86f141af91ab2d7cd011db47%7C
> 1%7C0%7C638260728110528650%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDA
> iLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=3D
> ONikRy3GwMEm0EWCqwfjVxodTVYK3XGUitvOCtdwkEI%3D&reserved=3D0)
> compiler: clang version 17.0.0
> (https://git/
> hub.com%2Fllvm%2Fllvm-project.git&data=3D05%7C01%7CSteven.French%40micro
> soft.com%7Cb15fd25d8a424332574308db8ec022d5%7C72f988bf86f141af91ab2d7c
> d011db47%7C1%7C0%7C638260728110528650%7CUnknown%7CTWFpbGZsb3d8eyJWIjoi
> MC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7
> C%7C&sdata=3Dm%2BNLdUsC7MNxn5YoYWroka3ANYO7CaMmQXCl2vVnoyU%3D&reserved=3D=
0
> 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a)
> reproduce:
> (https://dow/
> nload.01.org%2F0day-ci%2Farchive%2F20230727%2F202307270640.5ODmPwDl-lk
> p%40intel.com%2Freproduce&data=3D05%7C01%7CSteven.French%40microsoft.com
> %7Cb15fd25d8a424332574308db8ec022d5%7C72f988bf86f141af91ab2d7cd011db47
> %7C1%7C0%7C638260728110528650%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAw
> MDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sda
> ta=3DiFqAsjC5UOLz42Hhh4iM31%2BS7F1TAtLoreO9LbeK3tI%3D&reserved=3D0)
>
> If you fix the issue in a separate patch/commit (i.e. not just a new
> version of the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes:
> | https://lore/
> | .kernel.org%2Foe-kbuild-all%2F202307270640.5ODmPwDl-lkp%40intel.com%
> | 2F
> | &data=3D05%7C01%7CSteven.French%40microsoft.com%7C2cc584fd937a4cd5b9d0
> | 08
> | db8e29f75b%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C638260083130
> | 23
> | 4737%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJ
> | BT
> | iI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=3DAauGIxZRPM5DK1J5j6ly
> | Ep
> | jOkArxfVtIUAnmPcxcCQs%3D&reserved=3D0
>
> All warnings (new ones prefixed by >>):
>
> >> fs/smb/client/sess.c:160:5: warning: stack frame size (1152)
> >> exceeds limit (1024) in 'cifs_try_adding_channels'
> >> [-Wframe-larger-than]
>      160 | int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, str=
uct cifs_ses *ses)
>          |     ^
>    1 warning generated.
>
>
> vim +/cifs_try_adding_channels +160 fs/smb/client/sess.c
>
> b54034a73baf9f fs/cifs/sess.c Shyam Prasad N  2022-01-03  158
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  159  /*
> returns number of channels added */ 387ec58f339b0c fs/cifs/sess.c
> Ronnie Sahlberg 2020-12-14 @160  int cifs_try_adding_channels(struct
> cifs_sb_info *cifs_sb, struct cifs_ses *ses)
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  161  {
> 90c49fce1c43e1 fs/cifs/sess.c Paulo Alcantara 2023-04-21  162   struct TC=
P_Server_Info *server =3D ses->server;
> 724244cdb38285 fs/cifs/sess.c Shyam Prasad N  2021-07-19  163   int old_c=
han_count, new_chan_count;
> 724244cdb38285 fs/cifs/sess.c Shyam Prasad N  2021-07-19  164   int left;
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  165   int rc =
=3D 0;
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  166   int tries=
 =3D 0;
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  167   struct ci=
fs_server_iface *iface =3D NULL, *niface =3D NULL;
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  168
> 724244cdb38285 fs/cifs/sess.c Shyam Prasad N  2021-07-19  169   spin_lock=
(&ses->chan_lock);
> 724244cdb38285 fs/cifs/sess.c Shyam Prasad N  2021-07-19  170
> 724244cdb38285 fs/cifs/sess.c Shyam Prasad N  2021-07-19  171   new_chan_=
count =3D old_chan_count =3D ses->chan_count;
> 724244cdb38285 fs/cifs/sess.c Shyam Prasad N  2021-07-19  172   left =3D =
ses->chan_max - ses->chan_count;
> 724244cdb38285 fs/cifs/sess.c Shyam Prasad N  2021-07-19  173
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  174   if (left =
<=3D 0) {
> 88b024f556fcd5 fs/cifs/sess.c Shyam Prasad N  2021-11-19  175           s=
pin_unlock(&ses->chan_lock);
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  176           c=
ifs_dbg(FYI,
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  177            =
        "ses already at max_channels (%zu), nothing to open\n",
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  178            =
        ses->chan_max);
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  179           r=
eturn 0;
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  180   }
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  181
> 90c49fce1c43e1 fs/cifs/sess.c Paulo Alcantara 2023-04-21  182   if (serve=
r->dialect < SMB30_PROT_ID) {
> 53923e0fe2098f fs/cifs/sess.c Steve French    2022-02-16  183           s=
pin_unlock(&ses->chan_lock);
> 53923e0fe2098f fs/cifs/sess.c Steve French    2022-02-16  184           c=
ifs_dbg(VFS, "multichannel is not supported on this protocol version, use 3=
.0 or above\n");
> 53923e0fe2098f fs/cifs/sess.c Steve French    2022-02-16  185           r=
eturn 0;
> 53923e0fe2098f fs/cifs/sess.c Steve French    2022-02-16  186   }
> 53923e0fe2098f fs/cifs/sess.c Steve French    2022-02-16  187
> 90c49fce1c43e1 fs/cifs/sess.c Paulo Alcantara 2023-04-21  188   if (!(ser=
ver->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
> 9c2dc11df50d1c fs/cifs/sess.c Steve French    2021-05-07  189           s=
es->chan_max =3D 1;
> 724244cdb38285 fs/cifs/sess.c Shyam Prasad N  2021-07-19  190           s=
pin_unlock(&ses->chan_lock);
> 90c49fce1c43e1 fs/cifs/sess.c Paulo Alcantara 2023-04-21  191           c=
ifs_server_dbg(VFS, "no multichannel support\n");
> 9c2dc11df50d1c fs/cifs/sess.c Steve French    2021-05-07  192           r=
eturn 0;
> 9c2dc11df50d1c fs/cifs/sess.c Steve French    2021-05-07  193   }
> 724244cdb38285 fs/cifs/sess.c Shyam Prasad N  2021-07-19  194   spin_unlo=
ck(&ses->chan_lock);
> 9c2dc11df50d1c fs/cifs/sess.c Steve French    2021-05-07  195
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  196   /*
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  197    * Keep c=
onnecting to same, fastest, iface for all channels as
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  198    * long a=
s its RSS. Try next fastest one if not RSS or channel
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  199    * creati=
on fails.
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  200    */
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  201   spin_lock=
(&ses->iface_lock);
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  202   iface =3D=
 list_first_entry(&ses->iface_list, struct cifs_server_iface,
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  203            =
                iface_head);
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  204   spin_unlo=
ck(&ses->iface_lock);
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  205
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  206   while (le=
ft > 0) {
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  207
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  208           t=
ries++;
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  209           i=
f (tries > 3*ses->chan_max) {
> bbbf9eafbfdaa2 fs/cifs/sess.c Steve French    2020-05-30  210            =
       cifs_dbg(FYI, "too many channel open attempts (%d channels left to o=
pen)\n",
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  211            =
                left);
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  212            =
       break;
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  213           }
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  214
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  215           s=
pin_lock(&ses->iface_lock);
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  216           i=
f (!ses->iface_count) {
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  217            =
       spin_unlock(&ses->iface_lock);
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  218            =
       break;
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  219           }
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  220
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  221           l=
ist_for_each_entry_safe_from(iface, niface, &ses->iface_list,
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  222            =
                   iface_head) {
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  223            =
       /* skip ifaces that are unusable */
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  224            =
       if (!iface->is_active ||
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  225            =
           (is_ses_using_iface(ses, iface) &&
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  226            =
            !iface->rss_capable)) {
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  227            =
               continue;
> 65a37a34145ca6 fs/cifs/sess.c Aurelien Aptel  2019-11-20  228            =
       }
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  229
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  230            =
       /* take ref before unlock */
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  231            =
       kref_get(&iface->refcount);
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  232
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  233            =
       spin_unlock(&ses->iface_lock);
> 387ec58f339b0c fs/cifs/sess.c Ronnie Sahlberg 2020-12-14  234            =
       rc =3D cifs_ses_add_channel(cifs_sb, ses, iface);
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  235            =
       spin_lock(&ses->iface_lock);
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  236
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  237            =
       if (rc) {
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  238            =
               cifs_dbg(VFS, "failed to open extra channel on iface:%pIS rc=
=3D%d\n",
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  239            =
                        &iface->sockaddr,
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  240            =
                        rc);
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  241            =
               kref_put(&iface->refcount, release_iface);
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  242            =
               continue;
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  243            =
       }
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  244
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  245            =
       cifs_dbg(FYI, "successfully opened new channel on iface:%pIS\n",
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  246            =
                &iface->sockaddr);
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  247            =
       break;
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  248           }
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  249           s=
pin_unlock(&ses->iface_lock);
> aa45dadd34e44f fs/cifs/sess.c Shyam Prasad N  2022-01-01  250
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  251           l=
eft--;
> 724244cdb38285 fs/cifs/sess.c Shyam Prasad N  2021-07-19  252           n=
ew_chan_count++;
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  253   }
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  254
> 724244cdb38285 fs/cifs/sess.c Shyam Prasad N  2021-07-19  255   return ne=
w_chan_count - old_chan_count;
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  256  }
> d70e9fa5588476 fs/cifs/sess.c Aurelien Aptel  2019-09-20  257
>
> :::::: The code at line 160 was first introduced by commit
> :::::: 387ec58f339b0c45e3767395f11fa8dd3772131e cifs: simplify
> handling of cifs_sb/ctx->local_nls
>
> :::::: TO: Ronnie Sahlberg <lsahlber@redhat.com>
> :::::: CC: Steve French <stfrench@microsoft.com>
>
> --
> 0-DAY CI Kernel Test Service
> https://gith/
> ub.com%2Fintel%2Flkp-tests%2Fwiki&data=3D05%7C01%7CSteven.French%40micros=
oft.com%7Cb15fd25d8a424332574308db8ec022d5%7C72f988bf86f141af91ab2d7cd011db=
47%7C1%7C0%7C638260728110528650%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDA=
iLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=3DkSq=
8AIXuw4aqvh6X7af5shWbFVmIVgXpBpiLJEuKReE%3D&reserved=3D0
>