Go to file
Joel Stanley 9fdc543b0e fsi: scom: Fix error handling
[ Upstream commit d46fddd52d11eb6a3a7ed836f9f273e9cf8cd01c ]

SCOM error handling is made complex by trying to pass around two bits of
information: the function return code, and a status parameter that
represents the CFAM error status register.

The commit f72ddbe1d7 ("fsi: scom: Remove retries") removed the
"hidden" retries in the SCOM driver, in preference of allowing the
calling code (userspace or driver) to decide how to handle a failed
SCOM. However it introduced a bug by attempting to be smart about the
return codes that were "errors" and which were ok to fall through to the
status register parsing.

We get the following errors:

 - EINVAL or ENXIO, for indirect scoms where the value is invalid
 - EINVAL, where the size or address is incorrect
 - EIO or ETIMEOUT, where FSI write failed (aspeed master)
 - EAGAIN, where the master detected a crc error (GPIO master only)
 - EBUSY, where the bus is disabled (GPIO master in external mode)

In all of these cases we should fail the SCOM read/write and return the
error.

Thanks to Dan Carpenter for the detailed bug report.

Fixes: f72ddbe1d7 ("fsi: scom: Remove retries")
Link: https://lists.ozlabs.org/pipermail/linux-fsi/2021-November/000235.html
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20211207033811.518981-2-joel@jms.id.au
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:44 +02:00
Documentation vsprintf: Fix %pK with kptr_restrict == 0 2022-04-08 14:23:18 +02:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
arch powerpc/pseries: Fix use after free in remove_phb_dynamic() 2022-04-08 14:23:42 +02:00
block block: don't delete queue kobject before its children 2022-04-08 14:23:07 +02:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto crypto: authenc - Fix sleep in atomic context in decrypt_tail 2022-04-08 14:23:05 +02:00
drivers fsi: scom: Fix error handling 2022-04-08 14:23:44 +02:00
fs ext2: correct max file size computing 2022-04-08 14:23:35 +02:00
include netfilter: conntrack: Add and use nf_ct_set_auto_assign_helper_warned() 2022-04-08 14:23:42 +02:00
init init: make unknown command line param message clearer 2021-11-18 19:17:11 +01:00
ipc ipc/sem: do not sleep with a spin lock held 2022-02-08 18:34:03 +01:00
kernel kernel/resource: fix kfree() of bootmem memory again 2022-04-08 14:23:43 +02:00
lib vsprintf: Fix %pK with kptr_restrict == 0 2022-04-08 14:23:18 +02:00
mm mm/kmemleak: reset tag when compare object pointer 2022-04-08 14:22:56 +02:00
net tipc: fix the timer expires after interval 100ms 2022-04-08 14:23:43 +02:00
samples samples/bpf, xdpsock: Fix race when running for fix duration of time 2022-04-08 14:23:40 +02:00
scripts scripts/dtc: Call pkg-config POSIXly correct 2022-04-08 14:23:29 +02:00
security TOMOYO: fix __setup handlers return values 2022-04-08 14:23:35 +02:00
sound ASoC: amd: Fix reference to PCM buffer address 2022-04-08 14:23:22 +02:00
tools selftests/bpf/test_lirc_mode2.sh: Exit with proper code 2022-04-08 14:23:42 +02:00
usr usr/include/Makefile: add linux/nfc.h to the compile-test coverage 2022-02-01 17:27:15 +01:00
virt KVM: Fix lockdep false negative during host resume 2022-03-16 14:23:40 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: add Andrej Shadura 2021-10-18 20:22:03 -10:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
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 MAINTAINERS: adjust file entry for of_net.c after movement 2022-03-08 19:12:53 +01:00
Makefile Linux 5.15.32 2022-03-28 09:58:46 +02:00
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.