Commit log for commit 517d3cc15b
("[libata] ata_piix: Enable parallel scan") says:
This patch turns on parallel scanning for the ata_piix driver.
This driver is used on most netbooks (no AHCI for cheap storage it seems).
The scan is the dominating time factor in the kernel boot for these
devices; with this flag it gets cut in half for the device I used
for testing (eeepc).
Alan took a look at the driver source and concluded that it ought to be safe
to do for this driver. Alan has also checked with the hardware team.
and it is all true but once we put all things together additional
constraints for PATA controllers show up (some hardware registers
have per-host not per-port atomicity) and we risk misprogramming
the controller.
I used the following test to check whether the issue is real:
@@ -736,8 +736,20 @@ static void piix_set_piomode(struct ata_
(timings[pio][1] << 8);
}
pci_write_config_word(dev, master_port, master_data);
- if (is_slave)
+ if (is_slave) {
+ if (ap->port_no == 0) {
+ u8 tmp = slave_data;
+
+ while (slave_data == tmp) {
+ pci_read_config_byte(dev, slave_port, &tmp);
+ msleep(50);
+ }
+
+ dev_printk(KERN_ERR, &dev->dev, "PATA parallel scan "
+ "race detected\n");
+ }
pci_write_config_byte(dev, slave_port, slave_data);
+ }
/* Ensure the UDMA bit is off - it will be turned back on if
UDMA is selected */
and it indeed triggered the error message.
Lets fix all such races by adding an extra locking to ->set_piomode
and ->set_dmamode methods for PATA controllers.
[ Alan: would be better to take the host lock in libata-core for these
cases so that we fix all the adapters in one swoop. "Looks fine as a
temproary quickfix tho" ]
Cc: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Cc: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel:
drm/i915: Improve CRTDDC mapping by using VBT info
drm/i915: Fix CPU-spinning hangs related to fence usage by using an LRU.
drm/i915: Set crtc/clone mask in different output devices
drm/i915: Always use SDVO_B detect bit for SDVO output detection.
drm/i915: Fix typo that broke SVID1 in intel_sdvo_multifunc_encoder()
drm/i915: Check if BIOS enabled dual-channel LVDS on 8xx, not only on 9xx
drm/i915: Set the multiplier for SDVO on G33 platform
[mchehab@redhat.com: fix merge conflict and a few CodingStyle issues]
Signed-off-by: Steve Gotthardt <gotthardt@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Previous changesets broke Hauppauge devices and their GPIO configurations.
This changeset restores the LED & LNA functionality.
Signed-off-by: Michael Krufky <mkrufky@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Use VBT information to determine which DDC bus to use for CRTDCC.
Fall back to GPIOA if VBT info is not available.
Signed-off-by: David Müller <d.mueller@elsoft.ch>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Tested on: 855 (David), and 945GM, 965GM, GM45, and G45 (anholt)
acpi_video_put_one_device was attempting to remove sysfs entries and
unregister a backlight device without first checking that said backlight
device structure had been created.
Signed-off-by: Keith Packard <keithp@keithp.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
m68k,m68knommu: Wire up rt_tgsigqueueinfo and perf_counter_open
m68k: Fix redefinition of pgprot_noncached
arch/m68k/include/asm/motorola_pgalloc.h: fix kunmap arg
m68k: cnt reaches -1, not 0
m68k: count can reach 51, not 50
When setting the same GPIO number, multiple IRQ shared requests will be
done without freing the previous request. It will also try to free a
failed request or an already freed IRQ if 0 was written to the gpio file.
All these oops and leaks were fixed with the following solution: keep the
previous allocated GPIO (if any) still allocated in case the new request
fails. The alternative solution would desallocate the previous allocated
GPIO and set gpio as 0.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Samuel R. C. Vale <srcvale@holoscopio.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the BIOS reports an invalid throttling state (which seems to be
fairly common after system boot), a reset is done to state T0.
Because of a check in acpi_processor_get_throttling_ptc(), the reset
never actually gets executed, which results in the error reoccurring
on every access of for example /proc/acpi/processor/CPU0/throttling.
Add a 'force' option to acpi_processor_set_throttling() to ensure
the reset really takes effect.
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13389
This patch, together with the next one, fixes a regression introduced in
2.6.30, listed on the regression list. They have been available for 2.5
months now in bugzilla, but have not been picked up, despite various
reminders and without any reason given.
Google shows that numerous people are hitting this issue. The issue is in
itself relatively minor, but the bug in the code is clear.
The patches have been in all my kernels and today testing has shown that
throttling works correctly with the patches applied when the system
overheats (http://bugzilla.kernel.org/show_bug.cgi?id=13918#c14).
Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Summary:
Kernel panic arise when stack protection is enabled, since strncat will
add a null terminating byte '\0'; So in functions
like this one (wmi_query_block):
char wc[4]="WC";
....
strncat(method, block->object_id, 2);
...
the length of wc should be n+1 (wc[5]) or stack protection
fault will arise. This is not noticeable when stack protection is
disabled,but , isn't good either.
Config used: [CONFIG_CC_STACKPROTECTOR_ALL=y,
CONFIG_CC_STACKPROTECTOR=y]
Panic Trace
------------
.... stack-protector: kernel stack corrupted in : fa7b182c
2.6.30-rc8-obelisco-generic
call_trace:
[<c04a6c40>] ? panic+0x45/0xd9
[<c012925d>] ? __stack_chk_fail+0x1c/0x40
[<fa7b182c>] ? wmi_query_block+0x15a/0x162 [wmi]
[<fa7b182c>] ? wmi_query_block+0x15a/0x162 [wmi]
[<fa7e7000>] ? acer_wmi_init+0x00/0x61a [acer_wmi]
[<fa7e7135>] ? acer_wmi_init+0x135/0x61a [acer_wmi]
[<c0101159>] ? do_one_initcall+0x50+0x126
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13514
Signed-off-by: Costantino Leandro <lcostantino@gmail.com>
Signed-off-by: Carlos Corbacho <carlos@strangeworlds.co.uk>
Cc: Len Brown <len.brown@intel.com>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>