1 files changed, 78 insertions, 0 deletions

diff --git a/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.24/0031-USB-cdc-wdm-fix-lockup-on-error-in-wdm_read.patch b/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.24/0031-USB-cdc-wdm-fix-lockup-on-error-in-wdm_read.patch
new file mode 100644
index 00000000..3fb9fae1
--- /dev/null
+++ b/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.24/0031-USB-cdc-wdm-fix-lockup-on-error-in-wdm_read.patch
@@ -0,0 +1,78 @@
+From 6fb488dec8482c866a2c7cd4d1da06b85b8b28c7 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Bj=C3=B8rn=20Mork?= <bjorn@mork.no>
+Date: Mon, 2 Jul 2012 10:33:14 +0200
+Subject: [PATCH 031/109] USB: cdc-wdm: fix lockup on error in wdm_read
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+commit b086b6b10d9f182cd8d2f0dcfd7fd11edba93fc9 upstream.
+
+Clear the WDM_READ flag on empty reads to avoid running
+forever in an infinite tight loop, causing lockups:
+
+Jul  1 21:58:11 nemi kernel: [ 3658.898647] qmi_wwan 2-1:1.2: Unexpected error -71
+Jul  1 21:58:36 nemi kernel: [ 3684.072021] BUG: soft lockup - CPU#0 stuck for 23s! [qmi.pl:12235]
+Jul  1 21:58:36 nemi kernel: [ 3684.072212] CPU 0
+Jul  1 21:58:36 nemi kernel: [ 3684.072355]
+Jul  1 21:58:36 nemi kernel: [ 3684.072367] Pid: 12235, comm: qmi.pl Tainted: P           O 3.5.0-rc2+ #13 LENOVO 2776LEG/2776LEG
+Jul  1 21:58:36 nemi kernel: [ 3684.072383] RIP: 0010:[<ffffffffa0635008>]  [<ffffffffa0635008>] spin_unlock_irq+0x8/0xc [cdc_wdm]
+Jul  1 21:58:36 nemi kernel: [ 3684.072388] RSP: 0018:ffff88022dca1e70  EFLAGS: 00000282
+Jul  1 21:58:36 nemi kernel: [ 3684.072393] RAX: ffff88022fc3f650 RBX: ffffffff811c56f7 RCX: 00000001000ce8c1
+Jul  1 21:58:36 nemi kernel: [ 3684.072398] RDX: 0000000000000010 RSI: 000000000267d810 RDI: ffff88022fc3f650
+Jul  1 21:58:36 nemi kernel: [ 3684.072403] RBP: ffff88022dca1eb0 R08: ffffffffa063578e R09: 0000000000000000
+Jul  1 21:58:36 nemi kernel: [ 3684.072407] R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000002
+Jul  1 21:58:36 nemi kernel: [ 3684.072412] R13: 0000000000000246 R14: ffffffff00000002 R15: ffff8802281d8c88
+Jul  1 21:58:36 nemi kernel: [ 3684.072418] FS:  00007f666a260700(0000) GS:ffff88023bc00000(0000) knlGS:0000000000000000
+Jul  1 21:58:36 nemi kernel: [ 3684.072423] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
+Jul  1 21:58:36 nemi kernel: [ 3684.072428] CR2: 000000000270d9d8 CR3: 000000022e865000 CR4: 00000000000007f0
+Jul  1 21:58:36 nemi kernel: [ 3684.072433] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
+Jul  1 21:58:36 nemi kernel: [ 3684.072438] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
+Jul  1 21:58:36 nemi kernel: [ 3684.072444] Process qmi.pl (pid: 12235, threadinfo ffff88022dca0000, task ffff88022ff76380)
+Jul  1 21:58:36 nemi kernel: [ 3684.072448] Stack:
+Jul  1 21:58:36 nemi kernel: [ 3684.072458]  ffffffffa063592e 0000000100020000 ffff88022fc3f650 ffff88022fc3f6a8
+Jul  1 21:58:36 nemi kernel: [ 3684.072466]  0000000000000200 0000000100000000 000000000267d810 0000000000000000
+Jul  1 21:58:36 nemi kernel: [ 3684.072475]  0000000000000000 ffff880212cfb6d0 0000000000000200 ffff880212cfb6c0
+Jul  1 21:58:36 nemi kernel: [ 3684.072479] Call Trace:
+Jul  1 21:58:36 nemi kernel: [ 3684.072489]  [<ffffffffa063592e>] ? wdm_read+0x1a0/0x263 [cdc_wdm]
+Jul  1 21:58:36 nemi kernel: [ 3684.072500]  [<ffffffff8110adb7>] ? vfs_read+0xa1/0xfb
+Jul  1 21:58:36 nemi kernel: [ 3684.072509]  [<ffffffff81040589>] ? alarm_setitimer+0x35/0x64
+Jul  1 21:58:36 nemi kernel: [ 3684.072517]  [<ffffffff8110aec7>] ? sys_read+0x45/0x6e
+Jul  1 21:58:36 nemi kernel: [ 3684.072525]  [<ffffffff813725f9>] ? system_call_fastpath+0x16/0x1b
+Jul  1 21:58:36 nemi kernel: [ 3684.072557] Code: <66> 66 90 c3 83 ff ed 89 f8 74 16 7f 06 83 ff a1 75 0a c3 83 ff f4
+
+The WDM_READ flag is normally cleared by wdm_int_callback
+before resubmitting the read urb, and set by wdm_in_callback
+when this urb returns with data or an error.  But a crashing
+device may cause both a read error and cancelling all urbs.
+Make sure that the flag is cleared by wdm_read if the buffer
+is empty.
+
+We don't clear the flag on errors, as there may be pending
+data in the buffer which should be processed.  The flag will
+instead be cleared on the next wdm_read call.
+
+Signed-off-by: Bjørn Mork <bjorn@mork.no>
+Acked-by: Oliver Neukum <oneukum@suse.de>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
+---
+ drivers/usb/class/cdc-wdm.c |    2 ++
+ 1 files changed, 2 insertions(+), 0 deletions(-)
+
+diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c
+index 19fb5fa..9aaed0d 100644
+--- a/drivers/usb/class/cdc-wdm.c
++++ b/drivers/usb/class/cdc-wdm.c
+@@ -473,6 +473,8 @@ retry:
+                        goto retry;
+                }
+                if (!desc->reslength) { /* zero length read */
++                       dev_dbg(&desc->intf->dev, "%s: zero length - clearing WDM_READ\n", __func__);
++                       clear_bit(WDM_READ, &desc->flags);
+                        spin_unlock_irq(&desc->iuspin);
+                        goto retry;
+                }
+-- 
+1.7.7.6
+