linux_dsm_epyc7002/scripts/mod
Masahiro Yamada 7c8f5662c5 modpost: avoid false-positive file open error
One problem of grab_file() is that it cannot distinguish the following
two cases:

 - It cannot read the file (the file does not exist, or read permission
   is not set)

 - It can read the file, but the file size is zero

This is because grab_file() calls mmap(), which requires the mapped
length is greater than 0. Hence, grab_file() fails for both cases.

If an empty header file were included for checksum calculation, the
following warning would be printed:

  WARNING: modpost: could not open ...: Invalid argument

An empty file is a valid source file, so it should not fail.

Use read_text_file() instead. It can read a zero-length file.
Then, parse_file() will succeed with doing nothing.

Going forward, the first case (it cannot read the file) is a fatal
error. If the source file from which an object was compiled is missing,
something went wrong.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
..
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
devicetable-offsets.c Char/Misc driver patches for 5.7-rc1 2020-04-03 13:22:40 -07:00
empty.c
file2alias.c Char/Misc driver patches for 5.7-rc1 2020-04-03 13:22:40 -07:00
Makefile kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
mk_elfconfig.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
modpost.c modpost: add read_text_file() and get_line() helpers 2020-06-06 23:38:12 +09:00
modpost.h modpost: add read_text_file() and get_line() helpers 2020-06-06 23:38:12 +09:00
sumversion.c modpost: avoid false-positive file open error 2020-06-06 23:38:13 +09:00