linux/arch/parisc/kernel
Sven Schnelle 740f05f30a parisc: fix race condition in patching code
Assume the following ftrace code sequence that was patched in earlier by
ftrace_make_call():

PAGE A:
ffc:	addr of ftrace_caller()
PAGE B:
000:	0x6fc10080 /* stw,ma r1,40(sp) */
004:	0x48213fd1 /* ldw -18(r1),r1 */
008:	0xe820c002 /* bv,n r0(r1) */
00c:	0xe83f1fdf /* b,l,n .-c,r1 */

When a Code sequences that is to be patched spans a page break, we might
have already cleared the part on the PAGE A. If an interrupt is coming in
during the remap of the fixed mapping to PAGE B, it might execute the
patched function with only parts of the FTRACE code cleared. To prevent
this, clear the jump to our mini trampoline first, and clear the remaining
parts after this. This might also happen when patch_text() patches a
function that it calls during remap.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Cc: <stable@vger.kernel.org> # 5.2+
Signed-off-by: Helge Deller <deller@gmx.de>
2019-07-31 16:20:57 +02:00
..
syscalls parisc: Wire up clone3 syscall 2019-07-17 23:11:28 +02:00
.gitignore parisc: add arch/parisc/kernel/.gitignore 2008-10-10 16:32:28 +00:00
Makefile parisc: add dynamic ftrace 2019-06-08 12:56:29 +02:00
alternative.c parisc: Fix crash due alternative coding for NP iopdir_fdc bit 2019-06-06 14:25:22 +02:00
asm-offsets.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
audit.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cache.c parisc: Use __ro_after_init in cache.c 2019-05-10 21:00:44 +02:00
compat_audit.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
drivers.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
entry.S parisc: Wire up clone3 syscall 2019-07-17 23:11:28 +02:00
firmware.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
ftrace.c parisc: fix race condition in patching code 2019-07-31 16:20:57 +02:00
hardware.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 153 2019-05-30 11:26:32 -07:00
head.S parisc: Use __ro_after_init in head.S 2019-05-10 21:00:44 +02:00
hpmc.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 150 2019-05-30 11:25:19 -07:00
inventory.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
irq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 153 2019-05-30 11:26:32 -07:00
jump_label.c parisc: Add static branch and JUMP_LABEL feature 2019-05-06 00:10:03 +02:00
kgdb.c parisc: add KGDB support 2019-05-03 23:47:38 +02:00
kprobes.c parisc: Avoid kernel panic triggered by invalid kprobe 2019-07-17 23:11:28 +02:00
module.c Merge branch 'parisc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux 2019-07-09 12:08:15 -07:00
module.lds parisc: add dynamic ftrace 2019-06-08 12:56:29 +02:00
pa7300lc.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pacache.S parisc: Flush ITLB in flush_tlb_all_local() only on split TLB machines 2019-07-21 11:03:02 +02:00
parisc_ksyms.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
patch.c parisc: add spinlock to patch function 2019-06-08 12:56:26 +02:00
pci-dma.c dma-direct: handle DMA_ATTR_NON_CONSISTENT in common code 2019-06-25 14:27:58 +02:00
pci.c parisc: Use __ro_after_init in pci.c 2019-05-10 21:00:44 +02:00
pdc_chassis.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333 2019-06-05 17:37:06 +02:00
pdc_cons.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
pdt.c mm/memory_failure: Remove unused trapno from memory_failure 2018-01-23 12:17:42 -06:00
perf.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 153 2019-05-30 11:26:32 -07:00
perf_asm.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
perf_images.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
process.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
processor.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 153 2019-05-30 11:26:32 -07:00
ptrace.c parisc: Ensure userspace privilege for ptraced processes in regset functions 2019-07-17 23:11:27 +02:00
real2.S parisc: Fix and improve kernel stack unwinding 2018-08-13 09:54:17 +02:00
setup.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 153 2019-05-30 11:26:32 -07:00
signal.c signal: Remove task parameter from force_sig 2019-05-27 09:36:28 -05:00
signal32.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
signal32.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
smp.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
stacktrace.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
sys_parisc.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
sys_parisc32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
syscall.S parisc: Drop LDCW barrier in CAS code when running UP 2019-05-10 21:00:24 +02:00
time.c parisc: Use __ro_after_init in time.c 2019-05-10 21:00:45 +02:00
topology.c parisc: Add CPU topology support 2017-11-17 15:27:22 +01:00
traps.c signal: Remove the task parameter from force_sig_fault 2019-05-29 09:31:43 -05:00
unaligned.c Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2019-07-08 21:48:15 -07:00
unwind.c parisc: Use __ro_after_init in unwind.c 2019-05-10 21:00:45 +02:00
vmlinux.lds.S parisc: add dynamic ftrace 2019-06-08 12:56:29 +02:00