On Mon, Oct 21, 2024 at 3:03 PM Linus Walleij linus.walleij@linaro.org wrote:
This problem reported by Clement LE GOFFIC manifest when using CONFIG_KASAN_IN_VMALLOC and VMAP_STACK: https://lore.kernel.org/linux-arm-kernel/a1a1d062-f3a2-4d05-9836-3b098de9db6...
After some analysis it seems we are missing to sync the VMALLOC shadow memory in top level PGD to all CPUs.
Add some code to perform this sync, and the bug appears to go away.
As suggested by Ard, also perform a dummy read from the shadow memory of the new VMAP_STACK in the low level assembly.
Signed-off-by: Linus Walleij linus.walleij@linaro.org
As these are regressions that need to go in as fixes I'm putting them into Russell's patch tracker now.
The 9427/1 patch: https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=9427/1
Need to be avoided as it causes build regressions. Patch 1/3 supersedes it.
Yours, Linus Walleij