LinuxLists.cc - Linux 2.6.38-rc5

2011-02-16 04:16:46

Subject: Linux 2.6.38-rc5

Another week, another -rc.

Nothing much stands out here - we've fixed some regressions
(including, hopefully, a BUG_ON() due to the new RCU filename lookup
that Ubuntu people saw), and things look fairly normal.

Most of the changes are pretty spread out and small, with drivers/gpu
(radeon and i915) somewhat standing out from the pack. And to a lesser
degree drivers/rtc (converting some missed drivers to the
alarm_irq_enable methods) along with some ext4 updates (mainly the
"serialize unaligned async DIO" thing) standing out as being larger
than average.

There's also some device tree documentation movement that looks huge
if you look at traditional patches, but it's just moving files out of
the powerpc directory (since the whole device tree thing is generic
these days).

But most of it is pretty small. The appended ShortLog gives some flavor of it,

Linus

---
Ajit Khaparde (1):
benet: Avoid potential null deref in be_cmd_get_seeprom_data()

Al Viro (5):
nothing in do_follow_link() is going to see RCU
in do_lookup() split RCU and non-RCU cases of need_revalidate
split do_revalidate() into RCU and non-RCU cases
drop out of RCU in return_reval
get rid of nameidata_dentry_drop_rcu() calling nameidata_drop_rcu()

Alan Stern (3):
USB: prevent buggy hubs from crashing the USB stack
USB: fix race between root-hub resume and wakeup requests
USB: usb-storage: unusual_devs entry for Coby MP3 player

Alex Deucher (9):
drm/radeon/kms: fix interlaced modes on dce4+
drm/radeon/kms: add connector table for mac g5 9600
drm/radeon/kms: evergreen/ni big endian fixes (v2)
drm/radeon/kms: use linear aligned for 6xx/7xx bo blits
drm/radeon/kms: use linear aligned for evergreen/ni bo blits
drm/radeon/kms: improve 6xx/7xx CS error output
drm/radeon/kms: fix a few more atombios endian issues
drm/radeon/kms: add bounds checking to avivo pll algo
drm/radeon/kms: hopefully fix pll issues for real (v3)

Alexander Duyck (1):
ixgbe: limit VF access to network traffic

Alexander Stein (1):
Input: rotary_encoder - use proper irqflags

Alexander Strakh (2):
Input: wacom - fix error path in wacom_probe()
drivers/rtc/rtc-proc.c: add module_put on error path in rtc_proc_open()

Alexey Orishko (2):
CDC NCM errata updates for cdc.h
USB CDC NCM errata updates for cdc_ncm host driver

Amit Shah (3):
virtio: console: Move file back to drivers/char/
virtio: console: Wake up outvq on host notifications
virtio: console: Update Copyright

Anatolij Gustschin (1):
dma: ipu_idmac: do not lose valid received data in the irq handler

Andrea Arcangeli (1):
thp: prevent hugepages during args/env copying into the user stack

Anisse Astier (1):
ALSA: hda - add quirk for Ordissimo EVE using a realtek ALC662

Ari Kauppi (2):
oprofile: Fix usage of CONFIG_HW_PERF_EVENTS for
oprofile_perf_init and friends
ARM: oprofile: Fix backtraces in timer mode

Arnaldo Carvalho de Melo (1):
perf tools: Fix thread_map event synthesizing in top and record

Arvid Ephraim Picciani (1):
USB: cdc-acm: Adding second ACM channel support for Nokia N8

Ben Hutchings (1):
68360serial: Plumb in rs_360_get_icount()

Benny Halevy (1):
NFSD: use nfserr for status after decode_cb_op_status

Bjørn Forsman (1):
ARM: pxa/colibri: use correct SD detect pin

Bjørn Mork (1):
USB: io_edgeport: fix the reported firmware major and minor

Boaz Harrosh (1):
vfs: call rcu_barrier after ->kill_sb()

Bob Liu (1):
usb: musb: hsdma: change back to use musb_read/writew

Borislav Petkov (2):
amd64_edac: Fix DIMMs per DCTs output
x86: Fix mwait_usable section mismatch

Bruce Rogers (1):
virtio_net: Add schedule check to napi_enable call

Chris Mason (3):
md_make_request: don't touch the bio after calling make_request
Btrfs: fix page->private races
Btrfs: don't release pages when we can't clear the uptodate bits

Chris Wilson (7):
drm/i915: Invalidate TLB caches on SNB BLT/BSD rings
drm/i915/lvds: Restore dithering on native modes for gen2/3
drm/i915: Disable RC6 on Ironlake
drm/i915/sdvo: If we have an EDID confirm it matches the mode of
the connection
drm/i915: Trigger modesetting if force-audio changes
drm/i915/tv: Use polling rather than interrupt-based hotplug
drm/i915: Fix resume regression from 5d1d0cc

Chris Wright (3):
security: add cred argument to security_capable()
pci: use security_capable() when checking capablities during
config space read
pci: use security_capable() when checking capablities during
config space read

Christian Lamparter (1):
carl9170: fix typo in PS code

Clemens Ladisch (2):
ALSA: hrtimer: handle delayed timer interrupts
ALSA: hrtimer: remove superfluous tasklet invocation

Corey Minyard (1):
char/ipmi: fix OOPS caused by pnp_unregister_driver on unregistered driver

Curt Wohlgemuth (1):
ext4: Fix data corruption with multi-block writepages support

Cédric Cano (3):
drm/radeon: 6xx/7xx non-kms endian fixes
drm/radeon/kms: atombios big endian fixes
drm/radeon/kms: 6xx/7xx big endian fixes

Dan Rosenberg (1):
btrfs: prevent heap corruption in btrfs_ioctl_space_info()

Dan Williams (1):
dmaengine: add slave-dma maintainer

Dave Airlie (2):
drm/radeon: fix memory debugging since
d961db75ce86a84f1f04e91ad1014653ed7d9f46
drm/radeon: fix race between GPU reset and TTM delayed delete thread.

Dave Martin (1):
ARM: 6659/1: Thumb-2: Make CONFIG_OABI_COMPAT depend on
!CONFIG_THUMB2_KERNEL

David Henningsson (1):
ALSA: HDA: Add subwoofer quirk for Acer Aspire 8942G

David Miller (1):
klist: Fix object alignment on 64-bit.

David S. Miller (4):
net/caif: Fix dangling list pointer in freed object on error.
net: Fix lockdep regression caused by initializing netdev queues
too early.
isdn: hysdn: Kill (partially buggy) CVS regision log reporting.
x25: Do not reference freed memory.

David Teigland (1):
dlm: use single thread workqueues

Dirk Eibach (1):
hwmon: (lm63) Consider LM64 temperature offset

Dmitry Eremin-Solenikov (1):
ARM: 6658/1: collie: do actually pass locomo_info to locomo driver

Dmitry Torokhov (3):
Input: sysrq - rework re-inject logic
Revert "Input: do not pass injected events back to the
originating handler"
Input: ads7846 - check proper condition when freeing gpio

Don Fry (1):
iwlagn: Re-enable RF_KILL interrupt when down

Don Skidmore (3):
ixgbe: fix for 82599 erratum on Header Splitting
ixgbe: cleanup variable initialization
ixgbe: update version string

Don Zickus (1):
watchdog, nmi: Lower the severity of error messages

Duncan Laurie (1):
Input: serio - clear pending rescans after sysfs driver rebind

Emil Tantilov (1):
ixgbe: fix variable set but not used warnings by gcc 4.6

Eric Miao (1):
ARM: pxa: only save/restore registers when pm functions are defined

Eric Sandeen (3):
ext4: fix panic on module unload when stopping lazyinit thread
ext4: make grpinfo slab cache names static
ext4: serialize unaligned asynchronous DIO

Felipe Balbi (1):
usb: musb: disable double buffering when it's broken

Felix Fietkau (1):
mac80211: fix the skb cloned check in the tx path

Florian Fainelli (1):
e1000: add support for Marvell Alaska M88E1118R PHY

Geert Uytterhoeven (1):
m68knommu: Remove dependencies on nonexistent M68KNOMMU

Grant Likely (6):
dt: Move device tree documentation out of powerpc directory
dt: Remove obsolete description of powerpc boot interface
dt: add documentation of ARM dt boot interface
MAINTAINERS: Add entry for GPIO subsystem
MAINTAINERS: Add entry for GPIO subsystem
Revert "dt: add documentation of ARM dt boot interface"

Greg Ungerer (8):
m68knommu: fix use of un-defined _TIF_WORK_MASK
m68k: remove arch specific non-optimized memcmp()
m68knommu: add optimize memmove() function
m68knommu: fix mis-named variable int set_irq_chip loop
m68knommu: add missing linker __modver section
m68knommu: fix dereference of port.tty
m68knommu: remove use of IRQ_FLG_LOCK from 68360 platform support
m68knommu: set flow handler for secondary interrupt controller of 5249

Guennadi Liakhovetski (1):
spi/spi_sh_msiof: fix wrong address calculation, which leads to an Oops

Guenter Roeck (1):
hwmon: (emc1403) Fix I2C address range

Haiyang Zhang (1):
staging: hv: Enable sending GARP packet after live migration

Harsha Priya (1):
staging: sst: Fix for dmic capture on v2 pmic

Ian Abbott (2):
Staging: comedi: Add MODULE_LICENSE and similar to NI modules
Staging: Comedi: Fix a few NI module dependencies

Ilya Dryomov (1):
Btrfs - Fix memory leak in btrfs_init_new_device()

Ionut Nicu (1):
USB: ti_usb: fix module removal

J. Bruce Fields (9):
nfsd: don't leak dentry count on mnt_want_write failure
nfsd4: split up nfsd_break_deleg_cb
nfsd4: add helper function for lease setup
nfsd4: fix leak on allocation error
nfsd4: split lease setting into separate function
nfsd4: remove unused deleg dprintk's.
nfsd4: modify fi_delegations under recall_lock
nfsd4: acquire only one lease per file
nfsd: break lease on unlink due to rename

Jan Beulich (1):
x86: Fix section mismatch in LAPIC initialization

Janusz Krzysztofik (1):
ASoC: fill in snd_soc_pcm_runtime.card before calling
snd_soc_dai_link.init()

Jarkko Nikula (1):
usb: ehci-omap: Show fatal probing time errors to end user

Jean-Christophe PLAGNIOL-VILLARD (1):
USB: ftdi_sio: add ST Micro Connect Lite uart support

Jeff Layton (2):
cifs: clean up checks in cifs_echo_request
cifs: don't always drop malformed replies on the floor (try #3)

Jesper Juhl (5):
wireless, wl1251: Fix potential NULL pointer dereference in
wl1251_op_bss_info_changed()
USB SL811HS HCD: Fix memory leak in sl811h_urb_enqueue()
USB, Mass Storage, composite, gadget: Fix build failure and
memset of a struct
sis900: Fix mem leak in sis900_rx error path
radeon mkregtable: Add missing fclose() calls

Jesse Brandeburg (1):
e1000e: tx_timeout should not increment for non-hang events

Joerg Roedel (1):
KVM: SVM: Make sure KERNEL_GS_BASE is valid when loading gs_index

Johannes Berg (1):
mac80211: fix TX status cookie in HW offload case

Johannes Weiner (1):
vmscan: fix zone shrinking exit when scan work is done

John Stultz (3):
RTC: Fix rtc driver ioctl specific shortcutting
RTC: Convert rtc drivers to use the alarm_irq_enable method
RTC: Fix minor compile warning

Joseph Teichman (1):
ALSA: usbaudio - Enable the E-MU 0204 USB

Julia Lawall (1):
drivers/w1/masters/omap_hdq.c: add missing clk_put

Justin TerAvest (1):
cfq-iosched: Don't wait if queue already has requests.

KAMEZAWA Hiroyuki (1):
memcg: fix leak of accounting at failure path of hugepage collapsing

Kees Cook (2):
timer debug: Hide kernel addresses via %pK in /proc/timer_list
drm: do not leak kernel addresses via /proc/dri/*/vma

Ken Mills (1):
n_gsm: copy mtu over when configuring via ioctl interface

Konstantin Khorenko (1):
NFSD: memory corruption due to writing beyond the stat array

Krzysztof Wojcik (2):
Add raid1->raid0 takeover support
FIX: md: process hangs at wait_barrier after 0->10 takeover

Kukjin Kim (1):
ARM: S5PV310: Cleanup System MMU

Len Brown (1):
tools: turbostat: style updates

Linus Torvalds (4):
cap_syslog: accept CAP_SYS_ADMIN for now
Fix possible filp_cachep memory corruption
Revert "pci: use security_capable() when checking capablities
during config space read"
Linux 2.6.38-rc5

Lukas Czerner (1):
ext4: unregister features interface on module unload

Marek Olšák (3):
drm/radeon/kms: optimize CS state checking for r100->r500
drm/radeon/kms: fix tracking of BLENDCNTL, COLOR_CHANNEL_MASK,
and GB_Z on r300
drm/radeon/kms: check AA resolve registers on r300

Marek Vasut (1):
ARM: pxa: Properly configure PWM period for palm27x

Mark Brown (3):
ASoC: Create an AIF1ADCDAT signal widget to match AIF2
ASoC: Improve WM8994 digital power sequencing
ARM: SAMSUNG: Ensure struct sys_device is declared in plat/pm.h

Martin Schwidefsky (1):
s390: remove task_show_regs

Mian Yousaf Kaukab (2):
usb: musb: maintain three states for buffer mappings instead of two
usb: musb: introduce api for dma code to check compatibility
with usb request

Michael Buesch (1):
ssb-pcmcia: Fix parsing of invariants tuples

Michael Karcher (1):
ACPI / Video: Probe for output switch method when searching video devices.

Michael Williamson (1):
USB: ftdi_sio: Add VID=0x0647, PID=0x0100 for Acton Research spectrograph

Michal Simek (4):
microblaze: Fix IRQ flag handling for MSR=0
microblaze: Fix asm compilation warning
microblaze: Fix pte_update function
microblaze: Fix msr instruction detection

Michel Lespinasse (2):
mlock: fix race when munlocking pages in do_wp_page()
mlock: do not munlock pages in __do_fault()

Ming Lei (1):
usb: musb: fix kernel panic during s2ram(v2)

Mohammed Shafi Shajakhan (1):
ath9k: Fix possible double free of PAPRD skb's

Naga Chumbalkar (1):
x86, dmi, debug: Log board name (when present) in dmesg/oops output

NeilBrown (8):
md: revert change to raid_disks on failure.
md: simplify some 'if' conditionals in raid5_start_reshape.
md: fix the test for finding spares in raid5_start_reshape.
md: don't abort checking spares as soon as one cannot be added.
md: Remove the AllReserved flag for component devices.
md: Don't use remove_and_add_spares to remove failed devices
from a read-only array
md: don't clear curr_resync_completed at end of resync.
md: Don't allow slot_store while resync/recovery is happening.

Nick Holloway (1):
USB: Storage: Add unusual_devs entry for VTech Kidizoom

Nicolas de Pesloüan (1):
deb-pkg: Fix building outside of source tree (O=...).

Nitin Gupta (1):
staging: zram: fix data corruption issue

Pablo Neira Ayuso (1):
netfilter: nf_conntrack: set conntrack templates again if we
return NF_REPEAT

Paul Bolle (2):
devicetree-discuss is moderated for non-subscribers
x86, ioapic: Don't warn about non-existing IOAPICs if we have none

Pavankumar Kondeti (1):
USB: Fix trout build failure with ci13xxx_msm gadget

Peter Zijlstra (2):
Revert "lockdep, timer: Fix del_timer_sync() annotation"
x86: Fix text_poke_smp_batch() deadlock

Philippe De Muyter (2):
m68knommu: fix m548x_wdt.c compilation after headers renaming
m68knommu: Rename m548x_wdt.c to m54xx_wdt.c

Ping Cheng (1):
Input: wacom_w8001 - report resolution to userland

Rabin Vincent (1):
ARM: 6654/1: perf/oprofile: fix off-by-one in stack check

Rafael J. Wysocki (3):
ACPI: Fix acpi_os_read_memory() and acpi_os_write_memory() (v2)
ACPI / ACPICA: Avoid crashing if _PRW is defined for the root object
ACPI / Wakeup: Enable button GPEs unconditionally during initialization

Randy Dunlap (1):
can: softing_cs needs slab.h

Roland Stigge (1):
drivers/gpio/pca953x.c: add a mutex to fix race condition

Roland Vossen (1):
staging: brcm80211: bugfix for softmac crash on multi cpu configurations

Russell King (3):
ARM: Avoid building unsafe kernels on OMAP2 and MX3
ARM: make SWP emulation explicit on !CPU_USE_DOMAINS
ARM: fixup SMP alternatives in modules

Russell King - ARM Linux (2):
DMA: PL08x: fix infinite wait when terminating transfers
DMA: PL08x: fix channel pausing to timeout rather than lockup

Sascha Hauer (10):
dmaengine i.MX SDMA: Fix firmware loading
dmaengine i.MX sdma: set maximum segment size for our device
dmaengine i.MX sdma: check sg entries for valid addresses and lengths
dmaengine i.MX SDMA: do not initialize chan_id field
dmaengine i.MX SDMA: initialize dma capabilities outside channel loop
dmaengine i.MX SDMA: reserve channel 0 by not registering it
dmaengine i.MX dma: set maximum segment size for our device
dmaengine i.MX dma: check sg entries for valid addresses and lengths
dmaengine i.MX DMA: do not initialize chan_id field
dmaengine i.MX dma: initialize dma capabilities outside channel loop

Sergei Shtylyov (1):
usb: musb: core: fix IRQ check

Sergey Senozhatsky (1):
loop: queue_lock NULL pointer derefence in blk_throtl_exit

Shawn Guo (7):
dmaengine: imx-sdma: propagate error in sdma_probe() instead of
returning 0
dmaengine: imx-sdma: fix inconsistent naming in sdma_assign_cookie()
dmaengine: imx-sdma: remove IMX_DMA_SG_LOOP handling in
sdma_prep_slave_sg()
dmaengine: imx-sdma: set sdmac->status to DMA_ERROR in err_out
of sdma_prep_slave_sg()
dmaengine: imx-sdma: return sdmac->status in sdma_tx_status()
dmaengine: imx-sdma: correct sdmac->status in sdma_handle_channel_loop()
dmaengine: imx-sdma: fix up param for the last BD in sdma_prep_slave_sg()

Simon Arlott (1):
cdrom: support devices that have check_events but not media_changed

Sonic Zhang (1):
serial: bfin_5xx: split uart RX lock from uart port lock to avoid deadlock

Soren Hansen (1):
nbd: remove module-level ioctl mutex

Stefan Berger (1):
tpm_tis: Use timeouts returned from TPM

Stephen M. Cameron (1):
cciss: make cciss_revalidate not loop through CISS_MAX_LUNS
volumes unnecessarily.

Steve French (1):
[CIFS] Do not send SMBEcho requests on new sockets until SMBNegotiate

Sven Eckelmann (1):
batman-adv: Linearize fragment packets before merge

Takashi Iwai (2):
ALSA: hda - Fix missing CA initialization for HDMI/DP
ALSA: hda - Don't handle empty patch files

Tao Ma (1):
blktrace: Don't output messages if NOTIFY isn't set.

Tejun Heo (1):
ptrace: use safer wake up on ptrace_detach()

Theodore Ts'o (2):
ext4: fix up ext4 error handling
jbd2: call __jbd2_log_start_commit with j_state_lock write locked

Thomas Abraham (1):
ARM: S5PV310: Add support System MMU on SMDKV310

Thomas Gleixner (1):
x86: Readd missing irq_to_desc() in fixup_irq()

Thomas Renninger (1):
tools: turbostat: fix bitwise and operand

Tim Deegan (1):
fix jiffy calculations in calibrate_delay_direct to handle overflow

Tomoya (3):
pch_can: fix 800k comms issue
pch_can: fix rmmod issue
pch_can: fix module reload issue with MSI

Tomoya MORINAGA (1):
pch_can: fix tseg1/tseg2 setting issue

Toshiharu Okada (1):
pch_gbe: Fix the issue which a driver locks when rx offload is
set by ethtool

Tracey Dent (2):
drivers/block/Makefile: replace the use of <module>-objs with <module>-y
drivers/block/aoe/Makefile: replace the use of <module>-objs
with <module>-y

Trilok Soni (1):
Input: matrix_keypad - increase the limit of rows and columns

Tsutomu Itoh (1):
Btrfs: check return value of alloc_extent_map()

Vaibhav Bedia (1):
asoc: davinci: da830/omap-l137: correct cpu_dai_name

Vivek Goyal (2):
cfq: rename a function to give it more appropriate name
blkio-throttle: Avoid calling blkiocg_lookup_group() for root group

Vladislav Zolotarov (1):
bnx2x: Duplication in promisc mode

Wey-Yi Guy (1):
iwlagn: overwrite EEPROM chain setting for 6250 devices

Will Deacon (2):
ARM: 6656/1: hw_breakpoint: avoid UNPREDICTABLE behaviour when
reading DBGDSCR
ARM: 6657/1: hw_breakpoint: fix ptrace breakpoint advertising on
unsupported arch

Xiao Jiang (1):
drm: fix wrong usages of drm_device in DRM Developer's Guide

Yan, Zheng (1):
Btrfs: Fix balance panic

Yin Kangkai (1):
USB: EHCI: fix scheduling while atomic during suspend

Yinghai Lu (1):
memblock: don't adjust size in memblock_find_base()

Yu Tang (1):
ARM: pxa: fix mfpr_sync to read from valid offset

Yusuke Goda (1):
usb: r8a66597-udc: Fixed bufnum of Bulk

andrew hendry (1):
x25: possible skb leak on bad facilities

maximilian attems (1):
deb-pkg: Use $SRCARCH for include path

Łukasz Wojniłowicz (1):
ALSA: hda - switch lfe with side in mixer for 4930g

2011-02-16 11:14:11

by Eric Dumazet

[permalink] [raw]

Subject: Re: Linux 2.6.38-rc5

Le mardi 15 février 2011 à 20:16 -0800, Linus Torvalds a écrit :
> Another week, another -rc.
>
> Nothing much stands out here - we've fixed some regressions
> (including, hopefully, a BUG_ON() due to the new RCU filename lookup
> that Ubuntu people saw), and things look fairly normal.

Using this kernel on my dev machine (2x4x2 cpus), I hit BUG_ON() in
fs/namei.c:1461 on my kernel build (make -j16)

BUG_ON(inode != next.dentry->d_inode)

I do have DEBUG_PAGEALLOC and LOCKDEP on

2011-02-16 13:55:53

by Eric Dumazet

[permalink] [raw]

Subject: Re: Linux 2.6.38-rc5

Le mercredi 16 février 2011 à 12:14 +0100, Eric Dumazet a écrit :
> Le mardi 15 février 2011 à 20:16 -0800, Linus Torvalds a écrit :
> > Another week, another -rc.
> >
> > Nothing much stands out here - we've fixed some regressions
> > (including, hopefully, a BUG_ON() due to the new RCU filename lookup
> > that Ubuntu people saw), and things look fairly normal.
>
> Using this kernel on my dev machine (2x4x2 cpus), I hit BUG_ON() in
> fs/namei.c:1461 on my kernel build (make -j16)
>
> BUG_ON(inode != next.dentry->d_inode)
>
> I do have DEBUG_PAGEALLOC and LOCKDEP on
>
>

Since I hit this BUG_ON() even on boot, I spent some time tracking it.

I bisected the problem to commit 844a391799c25d9b
(nothing in do_follow_link() is going to see RCU)

Reverting this commit makes my machine happy again.

My filesystems are ext3

# mount
/dev/sda2 on / type ext3 (rw)
none on /proc type proc (rw)
none on /sys type sysfs (rw)
none on /dev/pts type devpts (rw,gid=5,mode=620)
usbfs on /proc/bus/usb type usbfs (rw)
/dev/sda6 on /appli type ext3 (rw)
/dev/sda1 on /boot type ext3 (rw)
none on /dev/shm type tmpfs (rw)
/dev/sda7 on /opt type ext3 (rw)
/dev/sda3 on /var type ext3 (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)

2011-02-16 15:47:15

[permalink] [raw]

Subject: Re: [PATCH] fix backlight brightness on intel LVDS panel after reopening lid

At Thu, 10 Mar 2011 09:45:18 +0100 (CET),
Indan Zupancic wrote:
>
> On Thu, March 10, 2011 08:49, Takashi Iwai wrote:
> > At Thu, 10 Mar 2011 06:50:09 +0100 (CET),
> > Indan Zupancic wrote:
> >>
> >> Hello,
> >>
> >> On Fri, March 4, 2011 19:47, Linus Torvalds wrote:
> >> > Alex, can you confirm that the revert of 951f3512dba5 plus the
> >> > one-liner patch from Takashi that Indan quoted also works for you?
> >> >
> >> > Linus
> >> >
> >> > On Thu, Mar 3, 2011 at 10:53 PM, Indan Zupancic <[email protected]> wrote:
> >> >>
> >> >> So please revert my patch and apply Takashi Iwai's, which fixes the
> >> >> most immediate bug without changing anything else. This should go
> >> >> in stable too.
> >> >
> >>
> >> I found another backlight bug:
> >>
> >> When suspending intel_panel_disable_backlight() is never called,
> >> but intel_panel_enable_backlight() is called at resume. With the
> >> effect that if the brightness was ever changed after screen
> >> blanking, the wrong brightness gets restored.
> >>
> >> This explains the weird behaviour I've seen. I didn't see it with
> >> combination mode, because then the brightness is always the same
> >> (zero or the maximum, the BIOS only uses LBPC on my system.) I'll
> >> send a patch in a moment.
> >>
> >> Alternative for reverting the combination mode removal (I can also
> >> redo the patch against the revert and Takashi's patch, if that's
> >> preferred):
> >>
> >> --
> >>
> >> drm/i915: Do handle backlight combination mode specially
> >>
> >> Add back the combination mode check, but with slightly cleaner code
> >> and the weirdness removed: No val >>= 1, but also no val &= ~1. The
> >> old code probably confused bit 0 with BLM_LEGACY_MODE, which is bit 16.
> >> The other change is clearer calculations: Just check for zero level
> >> explicitly instead of avoiding the divide-by-zero.
> >>
> >> Signed-off-by: Indan Zupancic <[email protected]>
> >>
> >> ---
> >>
> >> diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
> >> index d860abe..b05631a 100644
> >> --- a/drivers/gpu/drm/i915/intel_panel.c
> >> +++ b/drivers/gpu/drm/i915/intel_panel.c
> >> @@ -30,6 +30,10 @@
> >>
> >> #include "intel_drv.h"
> >>
> >> +#define PCI_LBPC 0xf4 /* legacy/combination backlight modes */
> >> +#define BLM_COMBINATION_MODE (1 << 30)
> >> +#define BLM_LEGACY_MODE (1 << 16)
> >> +
> >> void
> >> intel_fixed_panel_mode(struct drm_display_mode *fixed_mode,
> >> struct drm_display_mode *adjusted_mode)
> >> @@ -110,6 +114,22 @@ done:
> >> dev_priv->pch_pf_size = (width << 16) | height;
> >> }
> >>
> >> +/*
> >> + * What about gen 3? If there are no gen 3 systems with ASLE,
> >> + * then it doesn't matter, as we don't need to change the
> >> + * brightness. But then the gen 2 check can be removed too.
> >> + */
> >> +static int is_backlight_combination_mode(struct drm_device *dev)
> >> +{
> >> + struct drm_i915_private *dev_priv = dev->dev_private;
> >> +
> >> + if (INTEL_INFO(dev)->gen >= 4)
> >> + return I915_READ(BLC_PWM_CTL2) & BLM_COMBINATION_MODE;
> >> + if (IS_GEN2(dev))
> >> + return I915_READ(BLC_PWM_CTL) & BLM_LEGACY_MODE;
> >> + return 0;
> >> +}
> >> +
> >> static u32 i915_read_blc_pwm_ctl(struct drm_i915_private *dev_priv)
> >> {
> >> u32 val;
> >> @@ -163,9 +183,12 @@ u32 intel_panel_get_max_backlight(struct drm_device *dev)
> >> max >>= 17;
> >> } else {
> >> max >>= 16;
> >> + /* Ignore BLM_LEGACY_MODE bit */
> >> if (INTEL_INFO(dev)->gen < 4)
> >> max &= ~1;
> >> }
> >> + if (is_backlight_combination_mode(dev))
> >> + max *= 0xff;
> >> }
> >>
> >> DRM_DEBUG_DRIVER("max backlight PWM = %d\n", max);
> >> @@ -183,6 +206,12 @@ u32 intel_panel_get_backlight(struct drm_device *dev)
> >> val = I915_READ(BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
> >> if (IS_PINEVIEW(dev))
> >> val >>= 1;
> >> + if (is_backlight_combination_mode(dev)){
> >> + u8 lbpc;
> >> +
> >> + pci_read_config_byte(dev->pdev, PCI_LBPC, &lbpc);
> >> + val *= lbpc;
> >> + }
> >> }
> >>
> >> DRM_DEBUG_DRIVER("get backlight PWM = %d\n", val);
> >> @@ -205,6 +234,15 @@ void intel_panel_set_backlight(struct drm_device *dev, u32 level)
> >>
> >> if (HAS_PCH_SPLIT(dev))
> >> return intel_pch_panel_set_backlight(dev, level);
> >> +
> >> + if (level && is_backlight_combination_mode(dev)){
> >> + u32 max = intel_panel_get_max_backlight(dev);
> >> + u8 lpbc;
> >> +
> >> + lpbc = level * 0xff / max;
> >> + level /= lpbc;
> >
> > Hmm, I don't think this calculation is correct. This would result
> > in level of opregion over its limit. For example, assume the level
> > max = 100, so total max = 25500. Passing level=150 here will be:
> >
> > lbpc = 150 * 0xff / 25500 = 1.5 = 1
> > level = 150 / 1 = 150, which is over limit.
> >
> > More worse, lbpc can be zero when level is below 100 in the case
> > above...
>
> Yes, you're right. It seems that any simplification I try to do
> creates a new bug.
>
> Do you have any bright idea why the old code did val &= ~1; too?
> It seems obvious it's related to val >>= 1, but...

I guess it's for the case GEN < 4. But, no certain idea.

In my patch, I left it since this is relatively harmless, even if it's
not correct.

Takashi

2011-03-10 12:59:41

by Takashi Iwai

[permalink] [raw]

Subject: Re: [PATCH] fix backlight brightness on intel LVDS panel after reopening lid

At Thu, 10 Mar 2011 11:06:28 +0100 (CET),
Indan Zupancic wrote:
>
> On Thu, March 10, 2011 09:25, Takashi Iwai wrote:
> > At Thu, 10 Mar 2011 08:49:37 +0100,
> > Takashi Iwai wrote:
> >>
> >> At Thu, 10 Mar 2011 06:50:09 +0100 (CET),
> >> Indan Zupancic wrote:
> >> >
> >> > Hello,
> >> >
> >> > On Fri, March 4, 2011 19:47, Linus Torvalds wrote:
> >> > > Alex, can you confirm that the revert of 951f3512dba5 plus the
> >> > > one-liner patch from Takashi that Indan quoted also works for you?
> >> > >
> >> > > Linus
> >> > >
> >> > > On Thu, Mar 3, 2011 at 10:53 PM, Indan Zupancic <[email protected]> wrote:
> >> > >>
> >> > >> So please revert my patch and apply Takashi Iwai's, which fixes the
> >> > >> most immediate bug without changing anything else. This should go
> >> > >> in stable too.
> >> > >
> >> >
> >> > I found another backlight bug:
> >> >
> >> > When suspending intel_panel_disable_backlight() is never called,
> >> > but intel_panel_enable_backlight() is called at resume. With the
> >> > effect that if the brightness was ever changed after screen
> >> > blanking, the wrong brightness gets restored.
> >> >
> >> > This explains the weird behaviour I've seen. I didn't see it with
> >> > combination mode, because then the brightness is always the same
> >> > (zero or the maximum, the BIOS only uses LBPC on my system.) I'll
> >> > send a patch in a moment.
> >> >
> >> > Alternative for reverting the combination mode removal (I can also
> >> > redo the patch against the revert and Takashi's patch, if that's
> >> > preferred):
> >> >
> >> > --
> >> >
> >> > drm/i915: Do handle backlight combination mode specially
> >> >
> >> > Add back the combination mode check, but with slightly cleaner code
> >> > and the weirdness removed: No val >>= 1, but also no val &= ~1. The
> >> > old code probably confused bit 0 with BLM_LEGACY_MODE, which is bit 16.
> >> > The other change is clearer calculations: Just check for zero level
> >> > explicitly instead of avoiding the divide-by-zero.
> >> >
> >> > Signed-off-by: Indan Zupancic <[email protected]>
> >> >
> >> > ---
> >> >
> >> > diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
> >> > index d860abe..b05631a 100644
> >> > --- a/drivers/gpu/drm/i915/intel_panel.c
> >> > +++ b/drivers/gpu/drm/i915/intel_panel.c
> >> > @@ -30,6 +30,10 @@
> >> >
> >> > #include "intel_drv.h"
> >> >
> >> > +#define PCI_LBPC 0xf4 /* legacy/combination backlight modes */
> >> > +#define BLM_COMBINATION_MODE (1 << 30)
> >> > +#define BLM_LEGACY_MODE (1 << 16)
> >> > +
> >> > void
> >> > intel_fixed_panel_mode(struct drm_display_mode *fixed_mode,
> >> > struct drm_display_mode *adjusted_mode)
> >> > @@ -110,6 +114,22 @@ done:
> >> > dev_priv->pch_pf_size = (width << 16) | height;
> >> > }
> >> >
> >> > +/*
> >> > + * What about gen 3? If there are no gen 3 systems with ASLE,
> >> > + * then it doesn't matter, as we don't need to change the
> >> > + * brightness. But then the gen 2 check can be removed too.
> >> > + */
> >> > +static int is_backlight_combination_mode(struct drm_device *dev)
> >> > +{
> >> > + struct drm_i915_private *dev_priv = dev->dev_private;
> >> > +
> >> > + if (INTEL_INFO(dev)->gen >= 4)
> >> > + return I915_READ(BLC_PWM_CTL2) & BLM_COMBINATION_MODE;
> >> > + if (IS_GEN2(dev))
> >> > + return I915_READ(BLC_PWM_CTL) & BLM_LEGACY_MODE;
> >> > + return 0;
> >> > +}
> >> > +
> >> > static u32 i915_read_blc_pwm_ctl(struct drm_i915_private *dev_priv)
> >> > {
> >> > u32 val;
> >> > @@ -163,9 +183,12 @@ u32 intel_panel_get_max_backlight(struct drm_device *dev)
> >> > max >>= 17;
> >> > } else {
> >> > max >>= 16;
> >> > + /* Ignore BLM_LEGACY_MODE bit */
> >> > if (INTEL_INFO(dev)->gen < 4)
> >> > max &= ~1;
> >> > }
> >> > + if (is_backlight_combination_mode(dev))
> >> > + max *= 0xff;
> >> > }
> >> >
> >> > DRM_DEBUG_DRIVER("max backlight PWM = %d\n", max);
> >> > @@ -183,6 +206,12 @@ u32 intel_panel_get_backlight(struct drm_device *dev)
> >> > val = I915_READ(BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
> >> > if (IS_PINEVIEW(dev))
> >> > val >>= 1;
> >> > + if (is_backlight_combination_mode(dev)){
> >> > + u8 lbpc;
> >> > +
> >> > + pci_read_config_byte(dev->pdev, PCI_LBPC, &lbpc);
> >> > + val *= lbpc;
> >> > + }
> >> > }
> >> >
> >> > DRM_DEBUG_DRIVER("get backlight PWM = %d\n", val);
> >> > @@ -205,6 +234,15 @@ void intel_panel_set_backlight(struct drm_device *dev, u32 level)
> >> >
> >> > if (HAS_PCH_SPLIT(dev))
> >> > return intel_pch_panel_set_backlight(dev, level);
> >> > +
> >> > + if (level && is_backlight_combination_mode(dev)){
> >> > + u32 max = intel_panel_get_max_backlight(dev);
> >> > + u8 lpbc;
> >> > +
> >> > + lpbc = level * 0xff / max;
> >> > + level /= lpbc;
> >>
> >> Hmm, I don't think this calculation is correct. This would result
> >> in level of opregion over its limit. For example, assume the level
> >> max = 100, so total max = 25500. Passing level=150 here will be:
> >>
> >> lbpc = 150 * 0xff / 25500 = 1.5 = 1
> >> level = 150 / 1 = 150, which is over limit.
> >>
> >> More worse, lbpc can be zero when level is below 100 in the case
> >> above...
> >
> > That is, Chris' original code in that portion was correct:
> >
> > if (is_backlight_combination_mode(dev)){
> > u32 max = intel_panel_get_max_backlight(dev);
> > u8 lpbc;
> >
> > lpbc = level * 0xfe / max + 1;
> > level /= lpbc;
> > pci_write_config_byte(dev->pdev, PCI_LBPC, lpbc);
> > }
> >
> > This will fit within the right range.
> > Though, changing like below will give a bit better calculation,
> > closer to the real level.
> >
> > lpbc = level * 0xfe / max + 1;
> > level = (level + lpbc / 2) / lpbc;
>
> Indeed, though I don't think it makes much difference in practise.
>
> All in all it seems best to just revert my patch and apply your fix.
> Any "improvements" I may have are either buggy or can be added later.

Agreed. We should take a safer way.

> Care to make a new patch with the above improvement added? You can
> add my acked-by, for what it's worth.

OK, I'm going to send it now.

> At this point I don't even dare removing that "obviously" bogus
> val &= ~1; I bet it's an undocumented bit having some obscure
> secret function on not well tested systems.

Yes, I also left it...

Takashi