Linux kernel source tree
Go to file
Imre Deak a8ddac7c9f drm/i915: Avoid HPD poll detect triggering a new detect cycle
For the HPD interrupt functionality the HW depends on power wells in the
display core domain to be on. Accordingly when enabling these power
wells the HPD polling logic will force an HPD detection cycle to account
for hotplug events that may have happened when such a power well was
off.

Thus a detect cycle started by polling could start a new detect cycle if
a power well in the display core domain gets enabled during detect and
stays enabled after detect completes. That in turn can lead to a
detection cycle runaway.

To prevent re-triggering a poll-detect cycle make sure we drop all power
references we acquired during detect synchronously by the end of detect.
This will let the poll-detect logic continue with polling (matching the
off state of the corresponding power wells) instead of scheduling a new
detection cycle.

Fixes: 6cfe7ec02e ("drm/i915: Remove the unneeded AUX power ref from intel_dp_detect()")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112125
Reported-and-tested-by: Val Kulkov <val.kulkov@gmail.com>
Reported-and-tested-by: wangqr <wqr.prg@gmail.com>
Cc: Val Kulkov <val.kulkov@gmail.com>
Cc: wangqr <wqr.prg@gmail.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191028181517.22602-1-imre.deak@intel.com
2019-10-30 16:31:38 +02:00
arch ARM: SoC fixes 2019-10-05 17:18:43 -07:00
block block: sed-opal: fix sparse warning: convert __be64 data 2019-10-03 14:21:32 -06:00
certs PKCS#7: Refactor verify_pkcs7_signature() 2019-08-05 18:40:18 -04:00
crypto Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
Documentation doc: Update header files names 2019-10-25 12:06:21 +01:00
drivers drm/i915: Avoid HPD poll detect triggering a new detect cycle 2019-10-30 16:31:38 +02:00
fs elf: don't use MAP_FIXED_NOREPLACE for elf executable mappings 2019-10-06 13:53:27 -07:00
include drm/i915/gem: Make context persistence optional 2019-10-29 21:02:52 +00:00
init Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
ipc ipc/sem.c: convert to use built-in RCU list checking 2019-09-25 17:51:41 -07:00
kernel dma-mapping regression fix for 5.4-rc2 2019-10-06 11:10:15 -07:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-10-05 08:50:15 -07:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm Merge branch 'hugepage-fallbacks' (hugepatch patches from David Rientjes) 2019-09-28 14:26:47 -07:00
net nfc: fix memory leak in llcp_sock_bind() 2019-10-04 18:31:36 -07:00
samples rpmsg updates for v5.4 2019-09-22 10:58:15 -07:00
scripts scripts/setlocalversion: clear local variable to make it work for sh 2019-10-05 15:29:49 +09:00
security integrity: remove pointless subdir-$(CONFIG_...) 2019-10-05 15:29:49 +09:00
sound sound fixes for 5.4-rc1 2019-09-24 16:46:16 -07:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-10-05 08:50:15 -07:00
usr kbuild: update compile-test header list for v5.4-rc2 2019-10-05 15:29:49 +09:00
virt KVM/arm fixes for 5.4, take #1 2019-10-03 12:08:50 +02:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes
.gitignore Modules updates for v5.4 2019-09-22 10:34:46 -07:00
.mailmap Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2019-09-18 12:34:53 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS CREDITS: Update email address 2019-09-13 17:21:38 +03:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS drm-misc-next for 5.5: 2019-10-11 09:30:53 +10:00
Makefile Linux 5.4-rc2 2019-10-06 14:27:30 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.