Revision 38860b2c8bb1b92f61396eb06a63adff916fc31d authored by John David Anglin on 08 November 2021, 21:48:16 UTC, committed by Helge Deller on 13 November 2021, 21:10:56 UTC
For years, there have been random segmentation faults in userspace on SMP PA-RISC machines. It occurred to me that this might be a problem in set_pte_at(). MIPS and some other architectures do cache flushes when installing PTEs with the present bit set. Here I have adapted the code in update_mmu_cache() to flush the kernel mapping when the kernel flush is deferred, or when the kernel mapping may alias with the user mapping. This simplifies calls to update_mmu_cache(). I also changed the barrier in set_pte() from a compiler barrier to a full memory barrier. I know this change is not sufficient to fix the problem. It might not be needed. I have had a few days of operation with 5.14.16 to 5.15.1 and haven't seen any random segmentation faults on rp3440 or c8000 so far. Signed-off-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: Helge Deller <deller@gmx.de> Cc: stable@kernel.org # 5.12+
1 parent f0d1cfa
File | Mode | Size |
---|---|---|
ac97 | ||
aoa | ||
arm | ||
atmel | ||
core | ||
drivers | ||
firewire | ||
hda | ||
i2c | ||
isa | ||
mips | ||
oss | ||
parisc | ||
pci | ||
pcmcia | ||
ppc | ||
sh | ||
soc | ||
sparc | ||
spi | ||
synth | ||
usb | ||
virtio | ||
x86 | ||
xen | ||
Kconfig | -rw-r--r-- | 2.8 KB |
Makefile | -rw-r--r-- | 565 bytes |
ac97_bus.c | -rw-r--r-- | 2.9 KB |
last.c | -rw-r--r-- | 628 bytes |
sound_core.c | -rw-r--r-- | 14.3 KB |
Computing file changes ...