Go to file
Rasmus Villemoes 800cd6fb76 soc: fsl: qe: change return type of cpm_muram_alloc() to s32
There are a number of problems with cpm_muram_alloc() and its
callers. Most callers assign the return value to some variable and
then use IS_ERR_VALUE to check for allocation failure. However, when
that variable is not sizeof(long), this leads to warnings - and it is
indeed broken to do e.g.

  u32 foo = cpm_muram_alloc();
  if (IS_ERR_VALUE(foo))

on a 64-bit platform, since the condition

  foo >= (unsigned long)-ENOMEM

is tautologically false. There are also callers that ignore the
possibility of error, and then there are those that check for error by
comparing the return value to 0...

One could fix that by changing all callers to store the return value
temporarily in an "unsigned long" and test that. However, use of
IS_ERR_VALUE() is error-prone and should be restricted to things which
are inherently long-sized (stuff in pt_regs etc.). Instead, let's aim
for changing to the standard kernel style

  int foo = cpm_muram_alloc();
  if (foo < 0)
    deal_with_it()
  some->where = foo;

Changing the return type from unsigned long to s32 (aka signed int)
doesn't change the value that gets stored into any of the callers'
variables except if the caller was storing the result in a u64 _and_
the allocation failed, so in itself this patch should be a no-op.

Another problem with cpm_muram_alloc() is that it can certainly
validly return 0 - and except if some cpm_muram_alloc_fixed() call
interferes, the very first cpm_muram_alloc() call will return just
that. But that shows that both ucc_slow_free() and ucc_fast_free() are
buggy, since they assume that a value of 0 means "that field was never
allocated". We'll later change cpm_muram_free() to accept (and ignore)
a negative offset, so callers can use a sentinel of -1 instead of 0
and just unconditionally call cpm_muram_free().

Reviewed-by: Timur Tabi <timur@kernel.org>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Li Yang <leoyang.li@nxp.com>
2019-12-09 13:54:35 -06:00
arch soc: fsl: move cpm.h from powerpc/include/asm to include/soc/fsl 2019-12-09 13:54:34 -06:00
block block: fix memleak of bio integrity data 2019-12-05 11:38:36 -07:00
certs certs: Add wrapper function to check blacklisted binary hash 2019-11-12 12:25:50 +11:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-11-25 19:49:58 -08:00
Documentation powerpc updates for 5.5 #2 2019-12-06 13:36:31 -08:00
drivers soc: fsl: qe: change return type of cpm_muram_alloc() to s32 2019-12-09 13:54:35 -06:00
fs 9 cifs/smb3 fixes: two timestamp fixes, one oops fix (during oplock break) for stable, two fixes found in multichannel testing, two fixes for file create when using modeforsid mount parm 2019-12-08 12:12:18 -08:00
include soc: fsl: qe: change return type of cpm_muram_alloc() to s32 2019-12-09 13:54:35 -06:00
init init/Kconfig: fix indentation 2019-12-04 19:44:13 -08:00
ipc y2038: remove CONFIG_64BIT_TIME 2019-11-15 14:38:27 +01:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
lib lib/: fix Kconfig indentation 2019-12-07 11:00:19 -08:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm Merge branch 'akpm' (patches from Andrew) 2019-12-05 09:46:26 -08:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
samples samples/bpf: Fix broken xdp_rxq_info due to map order assumptions 2019-12-04 17:54:15 -08:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
security + Features 2019-12-03 12:51:35 -08:00
sound sound updates #2 for 5.5-rc1 2019-12-06 13:06:14 -08:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
usr arch: sembuf.h: make uapi asm/sembuf.h self-contained 2019-12-04 19:44:14 -08:00
virt KVM: Fix jump label out_free_* in kvm_init() 2019-11-23 11:29:17 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.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 modpost: dump missing namespaces into a single modules.nsdeps file 2019-11-11 20:10:01 +09:00
.mailmap Merge mainline/master into arm/fixes 2019-12-05 13:18:54 -08:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Linux 5.4-rc4 2019-10-29 04:43:29 -06:00
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 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
Makefile Linux 5.5-rc1 2019-12-08 14:57:55 -08:00
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.