Re: [3.14-rc1] cirrus driver problem (qemu)

From: Dave Airlie
Date: Mon Feb 03 2014 - 22:21:05 EST


On Tue, Feb 4, 2014 at 1:34 AM, Sabrina Dubroca <sd@xxxxxxxxxxxxxxx> wrote:
> When I boot 3.14-rc1 in qemu, I get the trace below. The console stops
> updating and I don't get a login prompt. I can login, but I can't see
> what I'm doing. I can login normally via SSH.
>
> If I revert the last commit in drivers/gpu/drm/cirrus:
>
> f4b4718b61d1d5a7442a4fd6863ea80c3a10e508 drm: ast,cirrus,mgag200: use drm_can_sleep
>
> the problem is solved.
>

Hi does the attach patch fix it?

Dave.
From c6feb881e00c8db9f9f73d099a08e86c5af79d50 Mon Sep 17 00:00:00 2001
From: Dave Airlie <airlied@xxxxxxxxxx>
Date: Tue, 4 Feb 2014 13:19:08 +1000
Subject: [PATCH] drm: add in_interrupt to drm_can_sleep list of things

This should stop us taking locks when we shouldn't in the console drivers,

[ 1.749341] ------------[ cut here ]------------
[ 1.749347] WARNING: CPU: 0 PID: 0 at kernel/locking/mutex.c:856 mutex_trylock+0x1e5/0x250()
[ 1.749348] DEBUG_LOCKS_WARN_ON(in_interrupt())
[ 1.749360] Modules linked in: ppdev cirrus syscopyarea sysfillrect sysimgblt drm_kms_helper evdev psmouse microcode serio_raw pcspkr ttm e1000 parport_pc parport processor button intel_agp drm intel_gtt i2c_piix4 ipv6 ext4 crc16 mbcache jbd2 sd_mod sr_mod cdrom ata_generic pata_acpi ata_piix 9pnet_virtio 9pnet libata scsi_mod
[ 1.749362] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.14.0-rc1-t1 #34
[ 1.749364] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 1.749366] 0000000000000009 ffff88001fc038c8 ffffffff814e8456 ffff88001fc03910
[ 1.749367] ffff88001fc03900 ffffffff8106a0dd ffff88001d3ff990 0000000000000010
[ 1.749368] 0000000000000000 00000000000001e0 ffff88001cc3b000 ffff88001fc03960
[ 1.749369] Call Trace:
[ 1.749372] <IRQ> [<ffffffff814e8456>] dump_stack+0x4d/0x6f
[ 1.749374] [<ffffffff8106a0dd>] warn_slowpath_common+0x7d/0xa0
[ 1.749375] [<ffffffff8106a14c>] warn_slowpath_fmt+0x4c/0x50
[ 1.749377] [<ffffffff814ebf45>] mutex_trylock+0x1e5/0x250
[ 1.749380] [<ffffffffa037888c>] cirrus_dirty_update+0x7c/0x2f0 [cirrus]
[ 1.749381] [<ffffffffa0378b2f>] cirrus_imageblit+0x2f/0x40 [cirrus]
[ 1.749388] [<ffffffff813188f4>] soft_cursor+0x1b4/0x250
[ 1.749390] [<ffffffff813181a3>] bit_cursor+0x613/0x650
[ 1.749391] [<ffffffff81313891>] ? get_color.isra.15+0x31/0x140

Reported-by: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx>
Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx>
---
include/drm/drmP.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 1d4a920..3a98664 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1665,7 +1665,7 @@ extern void drm_platform_exit(struct drm_driver *driver, struct platform_device
/* returns true if currently okay to sleep */
static __inline__ bool drm_can_sleep(void)
{
- if (in_atomic() || in_dbg_master() || irqs_disabled())
+ if (in_atomic() || in_dbg_master() || in_interrupt() || irqs_disabled())
return false;
return true;
}
--
1.8.4.2