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Brian Norris e9233917a7 mmc: core: Terminate infinite loop in SD-UHS voltage switch
This loop intends to retry a max of 10 times, with some implicit
termination based on the SD_{R,}OCR_S18A bit. Unfortunately, the
termination condition depends on the value reported by the SD card
(*rocr), which may or may not correctly reflect what we asked it to do.

Needless to say, it's not wise to rely on the card doing what we expect;
we should at least terminate the loop regardless. So, check both the
input and output values, so we ensure we will terminate regardless of
the SD card behavior.

Note that SDIO learned a similar retry loop in commit 0797e5f145
("mmc: core: Fixup signal voltage switch"), but that used the 'ocr'
result, and so the current pre-terminating condition looks like:

    rocr & ocr & R4_18V_PRESENT

(i.e., it doesn't have the same bug.)

This addresses a number of crash reports seen on ChromeOS that look
like the following:

    ... // lots of repeated: ...
    <4>[13142.846061] mmc1: Skipping voltage switch
    <4>[13143.406087] mmc1: Skipping voltage switch
    <4>[13143.964724] mmc1: Skipping voltage switch
    <4>[13144.526089] mmc1: Skipping voltage switch
    <4>[13145.086088] mmc1: Skipping voltage switch
    <4>[13145.645941] mmc1: Skipping voltage switch
    <3>[13146.153969] INFO: task halt:30352 blocked for more than 122 seconds.
    ...

Fixes: f2119df6b7 ("mmc: sd: add support for signal voltage switch procedure")
Cc: <stable@vger.kernel.org>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220914014010.2076169-1-briannorris@chromium.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2022-09-21 14:36:08 +02:00
Documentation I2C Documentation and binding fixes and improvements 2022-09-11 07:39:03 -04:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
arch arm64 fixes for -rc5 2022-09-11 07:48:21 -04:00
block block-6.0-2022-09-09 2022-09-09 15:03:08 -04:00
certs Kbuild updates for v5.20 2022-08-10 10:40:41 -07:00
crypto crypto: blake2b: effectively disable frame size warning 2022-08-10 17:59:11 -07:00
drivers mmc: core: Terminate infinite loop in SD-UHS voltage switch 2022-09-21 14:36:08 +02:00
fs Driver core fixes for 6.0-rc5 2022-09-09 15:08:40 -04:00
include IOMMU Fixes for Linux v6.0-rc4 2022-09-11 07:32:26 -04:00
init arm64 fixes for -rc3 2022-08-26 11:32:53 -07:00
io_uring io_uring-6.0-2022-09-09 2022-09-09 14:57:18 -04:00
ipc Updates to various subsystems which I help look after. lib, ocfs2, 2022-08-07 10:03:24 -07:00
kernel dma-mapping fixes for Linux 6.0 2022-09-10 12:18:19 -04:00
lib This push fixes a boot performance regression due to an unnecessary 2022-08-31 09:47:06 -07:00
mm mm: pagewalk: Fix race between unmap and page walker 2022-09-03 10:13:13 -07:00
net sch_sfb: Also store skb len before calling child enqueue 2022-09-08 11:12:58 +02:00
samples Tracing updates for 5.20 / 6.0 2022-08-05 09:41:12 -07:00
scripts Kbuild fixes for v6.0 (2nd) 2022-09-11 15:16:47 -04:00
security Landlock fix for v6.0-rc4 2022-09-02 15:24:08 -07:00
sound ASoC: Fixes for v6.0 2022-09-08 14:24:05 +02:00
tools linux-kselftest-kunit-fixes-6.0-rc5 2022-09-09 14:13:36 -04:00
usr Not a lot of material this cycle. Many singleton patches against various 2022-05-27 11:22:03 -07:00
virt KVM: Drop unnecessary initialization of "ops" in kvm_ioctl_create_device() 2022-08-19 04:05:43 -04:00
.clang-format PCI/DOE: Add DOE mailbox support functions 2022-07-19 15:38:04 -07:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore kbuild: split the second line of *.mod into *.usyms 2022-05-08 03:16:59 +09:00
.mailmap .mailmap: update Luca Ceresoli's e-mail address 2022-08-28 14:02:46 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS drm for 5.20/6.0 2022-08-03 19:52:08 -07:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS v6.0 second rc pull request 2022-09-09 14:46:44 -04:00
Makefile Linux 6.0-rc5 2022-09-11 16:22:01 -04:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README

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.