Date:	Sat, 20 Jun 2015 15:17:56 +0800
From:	Fengguang Wu <fengguang.wu@...el.com>
To:	"Luis R. Rodriguez" <mcgrof@...e.com>
Cc:	Ingo Molnar <mingo@...nel.org>, Borislav Petkov <bp@...e.de>,
	linux-media@...r.kernel.org, linux-kernel@...r.kernel.org,
	LKP <lkp@...org>
Subject: [x86/mm/pat, drivers/media/ivtv]  WARNING: CPU: 0 PID: 1 at
 drivers/media/pci/ivtv/ivtvfb.c:1270 ivtvfb_init()

Greetings,

0day kernel testing robot got the below dmesg and the first bad commit is

git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master

commit 1bf1735b478008c30acaff18ec6f4a3ff211c28a
Author:     Luis R. Rodriguez <mcgrof@...e.com>
AuthorDate: Mon Jun 15 10:28:16 2015 +0200
Commit:     Ingo Molnar <mingo@...nel.org>
CommitDate: Thu Jun 18 11:23:41 2015 +0200

    x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled
    
    We are burrying direct access to MTRR code support on
    x86 in order to take advantage of PAT. In the future, we
    also want to make the default behavior of ioremap_nocache()
    to use strong UC, at which point the use of mtrr_add() on
    those systems would make write-combining void.
    
    In order to help both enable us to later make strong
    UC default and in order to phase out direct MTRR access
    code, port the driver over to the arch_phys_wc_add() API
    and annotate that the device driver requires systems to
    boot with PAT disabled, with the 'nopat' kernel parameter.
    
    This is a workable compromise given that the hardware is
    really rare these days, and perhaps only some lost souls
    stuck with obsolete hardware are expected to be using this
    feature of the device driver.
    
    Signed-off-by: Luis R. Rodriguez <mcgrof@...e.com>
    Signed-off-by: Borislav Petkov <bp@...e.de>
    Acked-by: Andy Walls <awalls@...metrocast.net>
    Acked-by: Mauro Carvalho Chehab <mchehab@....samsung.com>
    Cc: Andrew Morton <akpm@...ux-foundation.org>
    Cc: Andy Lutomirski <luto@...capital.net>
    Cc: Antonino Daplas <adaplas@...il.com>
    Cc: Arnd Bergmann <arnd@...db.de>
    Cc: Borislav Petkov <bp@...en8.de>
    Cc: Brian Gerst <brgerst@...il.com>
    Cc: Daniel Vetter <daniel.vetter@...ll.ch>
    Cc: Dave Airlie <airlied@...hat.com>
    Cc: Dave Hansen <dave.hansen@...ux.intel.com>
    Cc: Denys Vlasenko <dvlasenk@...hat.com>
    Cc: Doug Ledford <dledford@...hat.com>
    Cc: H. Peter Anvin <hpa@...or.com>
    Cc: Jean-Christophe Plagniol-Villard <plagnioj@...osoft.com>
    Cc: Juergen Gross <jgross@...e.com>
    Cc: Linus Torvalds <torvalds@...ux-foundation.org>
    Cc: Michael S. Tsirkin <mst@...hat.com>
    Cc: Oleg Nesterov <oleg@...hat.com>
    Cc: Peter Zijlstra <peterz@...radead.org>
    Cc: Roger Pau Monné <roger.pau@...rix.com>
    Cc: Stefan Bader <stefan.bader@...onical.com>
    Cc: Suresh Siddha <sbsiddha@...il.com>
    Cc: Thomas Gleixner <tglx@...utronix.de>
    Cc: Ville Syrjälä <syrjala@....fi>
    Cc: bhelgaas@...gle.com
    Cc: konrad.wilk@...cle.com
    Cc: linux-media@...r.kernel.org
    Cc: tomi.valkeinen@...com
    Cc: toshi.kani@...com
    Link: http://lkml.kernel.org/r/1434053994-2196-2-git-send-email-mcgrof@do-not-panic.com
    Signed-off-by: Ingo Molnar <mingo@...nel.org>

+-----------------------------------------------------------+------------+------------+-----------------+
|                                                           | 957561ec0f | 1bf1735b47 | v4.1-rc8_061911 |
+-----------------------------------------------------------+------------+------------+-----------------+
| boot_successes                                            | 63         | 0          | 0               |
| boot_failures                                             | 0          | 22         | 13              |
| WARNING:at_drivers/media/pci/ivtv/ivtvfb.c:#ivtvfb_init() | 0          | 22         | 13              |
| backtrace:ivtvfb_init                                     | 0          | 22         | 13              |
| backtrace:warn_slowpath_fmt                               | 0          | 22         | 13              |
| backtrace:kernel_init_freeable                            | 0          | 22         | 13              |
+-----------------------------------------------------------+------------+------------+-----------------+

[   12.956506] ivtv: Start initialization, version 1.4.3
[   12.958238] ivtv: End initialization
[   12.959438] ------------[ cut here ]------------
[   12.974076] WARNING: CPU: 0 PID: 1 at drivers/media/pci/ivtv/ivtvfb.c:1270 ivtvfb_init+0x32/0xa3()
[   12.978017] ivtvfb needs PAT disabled, boot with nopat kernel parameter
[   12.980628] CPU: 0 PID: 1 Comm: swapper Not tainted 4.1.0-rc5-00034-g1bf1735 #2
[   12.995566] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[   12.999061]  ffffffff8d429cc8 ffff880010c5bdc8 ffffffff8cf47a88 ffff880010c5be08
[   13.001954]  ffffffff8c68e6d5 ffffffff8d977327 ffffffff8d9c6910 ffff880000139ef8
[   13.004862]  0000000000000000 ffffffff8d977327 0000000000000000 ffff880010c5be68
[   13.007636] Call Trace:
[   13.008469]  [<ffffffff8cf47a88>] dump_stack+0x19/0x1b
[   13.010185]  [<ffffffff8c68e6d5>] warn_slowpath_common+0x75/0xb0
[   13.024843]  [<ffffffff8d977327>] ? module_start+0xa4/0xa4
[   13.026876]  [<ffffffff8d977327>] ? module_start+0xa4/0xa4
[   13.029041]  [<ffffffff8c68e781>] warn_slowpath_fmt+0x41/0x50
[   13.031312]  [<ffffffff8d977359>] ivtvfb_init+0x32/0xa3
[   13.033362]  [<ffffffff8d945122>] do_one_initcall+0x19a/0x1ae
[   13.035444]  [<ffffffff8d945250>] kernel_init_freeable+0x11a/0x1a2
[   13.037434]  [<ffffffff8cf450f0>] ? rest_init+0xc0/0xc0
[   13.051468]  [<ffffffff8cf450f9>] kernel_init+0x9/0xf0
[   13.053252]  [<ffffffff8cf5e422>] ret_from_fork+0x42/0x70
[   13.055149]  [<ffffffff8cf450f0>] ? rest_init+0xc0/0xc0
[   13.057090] ---[ end trace 4c8a37b47d22b2c8 ]---
[   13.058748] Zoran MJPEG board driver version 0.10.1

git bisect start 1e5a271153487afd411894cfcbebed348c56e251 0f57d86787d8b1076ea8f9cbdddda2a46d534a27 --
git bisect good cfe18bb129d434b5229366eef876f076e9143bf4  # 16:20     22+      0  Merge 'pm/bleeding-edge' into devel-hourly-2015061911
git bisect  bad 062f9e0508bcab8d6a7f0ad64c2970dfd17fe4a0  # 16:25      0-     20  Merge 'tip/x86/mm' into devel-hourly-2015061911
git bisect good af6ae74ccfa5cb1d5688fb56b1dd6992a75d23fc  # 16:31     22+      2  Merge 'yinghai/for-pci-v4.1-rc8' into devel-hourly-2015061911
git bisect good 88dfb6767f528a66dd73b809afc87422f0628690  # 16:36     22+      0  Merge 'nfs/bugfixes' into devel-hourly-2015061911
git bisect good a7e50b0489e76438b0d3f9a17029ff4e11fd4e97  # 16:47     22+      0  Merge 'tip/timers/core' into devel-hourly-2015061911
git bisect good 6f5000ba3def9da5bcf360ecea9d0dd9598e5ac7  # 16:50     22+      0  Merge 'jolsa-perf/perf/per_thread' into devel-hourly-2015061911
git bisect good fbe7193aa4787f27c84216d130ab877efc310d57  # 16:55     20+      0  x86/mm/pat: Export pat_enabled()
git bisect good d838270e2516db11084bed4e294017eb7b646a75  # 17:00     21+      0  x86/mm, asm-generic: Add ioremap_wt() for creating Write-Through mappings
git bisect good 35a5a10411d87e24b46a7a9dda8d08ef9961b783  # 17:07     21+      0  x86/mm/pat: Extend set_page_memtype() to support Write-Through type
git bisect good 957561ec0fa8a701f60ca6a0f40cc46f5c554920  # 17:15     22+      0  drivers/block/pmem: Map NVDIMM in Write-Through mode
git bisect  bad 7ea402d01cb68224972dde3ae68bd41131b1c3a1  # 17:27      0-     13  x86/mm/pat, drivers/infiniband/ipath: Use arch_phys_wc_add() and require PAT disabled
git bisect  bad 1bf1735b478008c30acaff18ec6f4a3ff211c28a  # 17:31      0-     12  x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled
# first bad commit: [1bf1735b478008c30acaff18ec6f4a3ff211c28a] x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled
git bisect good 957561ec0fa8a701f60ca6a0f40cc46f5c554920  # 17:35     63+      0  drivers/block/pmem: Map NVDIMM in Write-Through mode
# extra tests with DEBUG_INFO
git bisect  bad 1bf1735b478008c30acaff18ec6f4a3ff211c28a  # 17:40      0-      2  x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled
# extra tests on HEAD of linux-devel/devel-hourly-2015061911
git bisect  bad 1e5a271153487afd411894cfcbebed348c56e251  # 17:40      0-     13  0day head guard for 'devel-hourly-2015061911'
# extra tests on tree/branch next/master
git bisect  bad c1ce6ea24e13fcdb61c75d7bb24377d11478b3c4  # 17:52      0-     66  Add linux-next specific files for 20150619
# extra tests with first bad commit reverted
git bisect good 9025feea072ddf7e82da7c400193202e8c06e867  # 18:19     66+      0  Revert "x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled"
# extra tests on tree/branch linus/master
git bisect good e640a280ccb9c448a3d9d522ea730ce00efa8cf0  # 18:23     63+      0  Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
# extra tests on tree/branch next/master
git bisect  bad c1ce6ea24e13fcdb61c75d7bb24377d11478b3c4  # 18:23      0-     66  Add linux-next specific files for 20150619


This script may reproduce the error.

----------------------------------------------------------------------------
#!/bin/bash

kernel=$1
initrd=quantal-core-x86_64.cgz

wget --no-clobber https://github.com/fengguang/reproduce-kernel-bug/raw/master/initrd/$initrd

kvm=(
	qemu-system-x86_64
	-enable-kvm
	-cpu kvm64
	-kernel $kernel
	-initrd $initrd
	-m 300
	-smp 2
	-device e1000,netdev=net0
	-netdev user,id=net0
	-boot order=nc
	-no-reboot
	-watchdog i6300esb
	-rtc base=localtime
	-serial stdio
	-display none
	-monitor null 
)

append=(
	hung_task_panic=1
	earlyprintk=ttyS0,115200
	systemd.log_level=err
	debug
	apic=debug
	sysrq_always_enabled
	rcupdate.rcu_cpu_stall_timeout=100
	panic=-1
	softlockup_panic=1
	nmi_watchdog=panic
	oops=panic
	load_ramdisk=2
	prompt_ramdisk=0
	console=ttyS0,115200
	console=tty0
	vga=normal
	root=/dev/ram0
	rw
	drbd.minor_count=8
)

"${kvm[@]}" --append "${append[*]}"
----------------------------------------------------------------------------

---
0-DAY kernel test infrastructure                Open Source Technology Center
http://lists.01.org/mailman/listinfo/kbuild                 Intel Corporation

View attachment "dmesg-quantal-intel12-45:20150619173143:x86_64-randconfig-n0-06191536:4.1.0-rc5-00034-g1bf1735:2" of type "text/plain" (58793 bytes)

View attachment "config-4.1.0-rc5-00034-g1bf1735" of type "text/plain" (76724 bytes)

Powered by blists - more mailing lists