linux-xiaomi-chiron

Linux mainline fork with MSM8998 patches | https://mainline.space | Currently supported devices: OnePlus 5/5T, Xiaomi Mi 6, F(x)tec Pro¹ (2019 QX1000 model) & Sony Xperia XZ Premium (UNTESTED!)

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Luis R. Rodriguez 90d41e74a9 firmware: fix batched requests - send wake up on failure on direct lookups Fix batched requests from waiting forever on failure. The firmware API batched requests feature has been broken since the API call request_firmware_direct() was introduced on commit `bba3a87e98` ("firmware: Introduce request_firmware_direct()"), added on v3.14 iff the firmware being requested was not present in certain kernel builds [0]. When no firmware is found the worker which goes on to finish never informs waiters queued up of this, so any batched request will stall in what seems to be forever (MAX_SCHEDULE_TIMEOUT). Sadly, a reboot will also stall, as the reboot notifier was only designed to kill custom fallback workers. The issue seems to the user as a type of soft lockup, what actually happens underneath the hood is a wait call which never completes as we failed to issue a completion on error. For device drivers with optional firmware schemes (ie, Intel iwlwifi, or Netronome -- even though it uses request_firmware() and not request_firmware_direct()), this could mean that when you boot a system with multiple cards the firmware will seem to never load on the system, or that the card is just not responsive even the driver initialization. Due to differences in scheduling possible this should not always trigger -- one would need to to ensure that multiple requests are in place at the right time for this to work, also release_firmware() must not be called prior to any other incoming request. The complexity may not be worth supporting batched requests in the future given the wait mechanism is only used also for the fallback mechanism. We'll keep it for now and just fix it. Its reported that at least with the Intel WiFi cards on one system this issue was creeping up 50% of the boots [0]. Before this commit batched requests testing revealed: ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=y Most common Linux distribution setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() FAIL OK request_firmware_direct() FAIL OK request_firmware_nowait(uevent=true) FAIL OK request_firmware_nowait(uevent=false) FAIL OK ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=n Only possible if CONFIG_DELL_RBU=n and CONFIG_LEDS_LP55XX_COMMON=n, rare. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() FAIL OK request_firmware_direct() FAIL OK request_firmware_nowait(uevent=true) FAIL OK request_firmware_nowait(uevent=false) FAIL OK ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y CONFIG_FW_LOADER_USER_HELPER=y Google Android setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() OK OK request_firmware_direct() FAIL OK request_firmware_nowait(uevent=true) OK OK request_firmware_nowait(uevent=false) OK OK ============================================================================ Ater this commit batched testing results: ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=y Most common Linux distribution setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() OK OK request_firmware_direct() OK OK request_firmware_nowait(uevent=true) OK OK request_firmware_nowait(uevent=false) OK OK ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=n Only possible if CONFIG_DELL_RBU=n and CONFIG_LEDS_LP55XX_COMMON=n, rare. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() OK OK request_firmware_direct() OK OK request_firmware_nowait(uevent=true) OK OK request_firmware_nowait(uevent=false) OK OK ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y CONFIG_FW_LOADER_USER_HELPER=y Google Android setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() OK OK request_firmware_direct() OK OK request_firmware_nowait(uevent=true) OK OK request_firmware_nowait(uevent=false) OK OK ============================================================================ [0] https://bugzilla.kernel.org/show_bug.cgi?id=195477 Cc: stable <stable@vger.kernel.org> # v3.14 Fixes: `bba3a87e98` ("firmware: Introduce request_firmware_direct()" Reported-by: Nicolas <nbroeking@me.com> Reported-by: John Ewalt <jewalt@lgsinnovations.com> Reported-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2017-08-10 13:54:16 -07:00
arch	Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-07-15 12:00:42 -07:00
block	Merge branch 'for-linus' of git://git.kernel.dk/linux-block	2017-07-11 15:36:52 -07:00
certs	modsign: add markers to endif-statements in certs/Makefile	2017-07-14 11:01:37 +10:00
crypto	Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6	2017-07-14 22:49:50 -07:00
Documentation	This series converts a number of top-level documents to the RST format	2017-07-15 12:58:58 -07:00
drivers	firmware: fix batched requests - send wake up on failure on direct lookups	2017-08-10 13:54:16 -07:00
firmware	firmware/Makefile: force recompilation if makefile changes	2017-05-08 17:15:10 -07:00
fs	Add wait_for_random_bytes() and get_random_*_wait() functions so that	2017-07-15 12:44:02 -07:00
include	Add wait_for_random_bytes() and get_random_*_wait() functions so that	2017-07-15 12:44:02 -07:00
init	random: do not ignore early device randomness	2017-07-12 16:26:00 -07:00
ipc	ipc/util.h: update documentation for ipc_getref() and ipc_putref()	2017-07-12 16:26:02 -07:00
kernel	Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-07-15 12:00:42 -07:00
lib	Add wait_for_random_bytes() and get_random_*_wait() functions so that	2017-07-15 12:44:02 -07:00
mm	Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-07-15 12:00:42 -07:00
net	Add wait_for_random_bytes() and get_random_*_wait() functions so that	2017-07-15 12:44:02 -07:00
samples	Merge branch 'akpm' (patches from Andrew)	2017-07-13 12:38:49 -07:00
scripts	Kbuild updates for v4.13 (2nd)	2017-07-13 13:37:57 -07:00
security	KEYS: DH: validate __spare field	2017-07-14 11:01:38 +10:00
sound	sound fixes for 4.13-rc1	2017-07-14 12:44:00 -07:00
tools	Merge branch 'akpm' (patches from Andrew)	2017-07-14 21:57:25 -07:00
usr	ramfs: clarify help text that compression applies to ramfs as well as legacy ramdisk.	2017-07-06 16:24:30 -07:00
virt	Second batch of KVM updates for v4.13	2017-07-15 10:18:16 -07:00
.cocciconfig	scripts: add Linux .cocciconfig for coccinelle	2016-07-22 12:13:39 +02:00
.get_maintainer.ignore	Add hch to .get_maintainer.ignore	2015-08-21 14:30:10 -07:00
.gitattributes	.gitattributes: set git diff driver for C source code files	2016-10-07 18:46:30 -07:00
.gitignore	kbuild: Add support to generate LLVM assembly files	2017-04-25 08:13:52 +09:00
.mailmap	power supply and reset changes for the v4.12 series (part 2)	2017-05-12 12:02:21 -07:00
COPYING	[PATCH] update FSF address in COPYING	2005-09-10 10:06:29 -07:00
CREDITS	avr32: remove support for AVR32 architecture	2017-05-01 09:27:15 +02:00
Kbuild	kbuild: Consolidate header generation from ASM offset information	2017-04-13 05:43:37 +09:00
Kconfig	kbuild: migrate all arch to the kconfig mainmenu upgrade	2010-09-19 22:54:11 -04:00
MAINTAINERS	Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus	2017-07-15 10:59:54 -07:00
Makefile	Linux v4.13-rc1	2017-07-15 15:22:10 -07:00
README	README: add a new README file, pointing to the Documentation/	2016-10-24 08:12:35 -02:00

README

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

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

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.