Philipp Rudo ad03b821fb s390/purgatory: Fix crash with expoline enabled ... When the kernel is built with CONFIG_EXPOLINE=y and a compiler with indirect branch mitigation enabled the purgatory crashes. The reason for that is that the macros defined for expoline are used in mem.S. These macros define new sections (.text.__s390x_indirect_*) which are marked executable. Due to the missing linker script those sections are linked to address 0, just as the .text section. In combination with the entry point also being at address 0 this causes the purgatory load code (kernel/kexec_file.c: kexec_purgatory_setup_sechdrs) to update the entry point twice. Thus the old kernel jumps to some 'random' address causing the crash. To fix this turn off expolines for the purgatory. There is no problem with this in this case due to the fact that the purgatory only runs once and the tlb is purged (diag 308) in the end. Fixes: 840798a1f5 ("s390/kexec_file: Add purgatory") Cc: <stable@vger.kernel.org> # 4.17 Signed-off-by: Philipp Rudo <prudo@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>		2018-07-06 08:47:48 +02:00
..
.gitignore	s390/kexec_file: add generated files to .gitignore	2018-04-16 09:10:23 +02:00
head.S	s390/kexec_file: Add crash support to image loader	2018-04-16 09:10:22 +02:00
Makefile	s390/purgatory: Fix crash with expoline enabled	2018-07-06 08:47:48 +02:00
purgatory.c	s390/kexec_file: Add crash support to image loader	2018-04-16 09:10:22 +02:00