linux_dsm_epyc7002/arch/arm/boot/compressed
Ard Biesheuvel 011b9e1c2a ARM: 9056/1: decompressor: fix BSS size calculation for LLVM ld.lld
commit c4e792d1acce31c2eb7b9193ab06ab94de05bf42 upstream.

The LLVM ld.lld linker uses a different symbol type for __bss_start,
resulting in the calculation of KBSS_SZ to be thrown off. Up until now,
this has gone unnoticed as it only affects the appended DTB case, but
pending changes for ARM in the way the decompressed kernel is cleaned
from the caches has uncovered this problem.

On a ld.lld build:

  $ nm vmlinux |grep bss_
  c1c22034 D __bss_start
  c1c86e98 B __bss_stop

resulting in

  $ readelf -s arch/arm/boot/compressed/vmlinux | grep bss_size
  433: c1c86e98     0 NOTYPE  GLOBAL DEFAULT  ABS _kernel_bss_size

which is obviously incorrect, and may cause the cache clean to access
unmapped memory, or cause the size calculation to wrap, resulting in no
cache clean to be performed at all.

Fix this by updating the sed regex to take D type symbols into account.

Link: https://lore.kernel.org/linux-arm-kernel/6c65bcef-d4e7-25fa-43cf-2c435bb61bb9@collabora.com/
Link: https://lore.kernel.org/linux-arm-kernel/20210205085220.31232-1-ardb@kernel.org/

Cc: <stable@vger.kernel.org> # v4.19+
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reported-by: Guillaume Tucker <guillaume.tucker@collabora.com>
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-11 14:47:12 +02:00
..
.gitignore ARM: 8969/1: decompressor: simplify libfdt builds 2020-04-29 13:28:59 +01:00
atags_to_fdt.c ARM: zImage: atags_to_fdt: Fix node names on added root nodes 2021-02-03 23:28:44 +01:00
big-endian.S ARM: 8933/1: replace Sun/Solaris style flag on section directive 2019-11-15 22:21:19 +00:00
debug.S ARM: 9005/1: debug: Select flow control for all debug UARTs 2020-09-15 14:35:28 +01:00
decompress.c arch/arm/boot/compressed/decompress.c: fix build error due to lz4 changes 2019-06-01 15:51:31 -07:00
efi-header.S efi/libstub: Add missing prototype for PE/COFF entry point 2020-05-23 11:01:57 +02:00
fdt_ro.c ARM: 8969/1: decompressor: simplify libfdt builds 2020-04-29 13:28:59 +01:00
fdt_rw.c ARM: 8969/1: decompressor: simplify libfdt builds 2020-04-29 13:28:59 +01:00
fdt_wip.c ARM: 8969/1: decompressor: simplify libfdt builds 2020-04-29 13:28:59 +01:00
fdt.c ARM: 8969/1: decompressor: simplify libfdt builds 2020-04-29 13:28:59 +01:00
head-sa1100.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
head-sharpsl.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
head-xscale.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
head.S ARM: efistub: replace adrl pseudo-op with adr_l macro invocation 2021-03-17 17:06:26 +01:00
ll_char_wr.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
Makefile ARM: 9056/1: decompressor: fix BSS size calculation for LLVM ld.lld 2021-05-11 14:47:12 +02:00
misc.c Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm 2018-04-09 09:19:30 -07:00
misc.h ARM: decompressor: fix warning introduced in fortify patch 2018-04-05 23:56:40 +01:00
piggy.S ARM: 8933/1: replace Sun/Solaris style flag on section directive 2019-11-15 22:21:19 +00:00
string.c ARM: boot: add strrchr function 2018-03-01 12:02:48 -06:00
vmlinux.lds.S ARM development for 5.10-rc1: 2020-10-20 09:18:31 -07:00