Hello Christophe, Il giorno mar, 08/12/2020 alle 05.24 +0000, Christophe Leroy ha scritto: > low_sleep_handler() can't restore the context from standard > stack because the stack can hardly be accessed with MMU OFF. > > Store everything in a global storage area instead of storing > a pointer to the stack in that global storage area. > > To avoid a complete churn of the function, still use r1 as > the pointer to the storage area during restore. > > Reported-by: Giuseppe Sacco <giuse...@sguazz.it> > Fixes: cd08f109e262 ("powerpc/32s: Enable CONFIG_VMAP_STACK") > Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu> > --- > This is only build tested. Giuseppe can you test it ? Thanks. > > v2: Changed an erroneous 'addis' to 'addi' ; Using bss instead of > data section > Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu> > --- > arch/powerpc/platforms/Kconfig.cputype | 2 +- > arch/powerpc/platforms/powermac/sleep.S | 132 +++++++++++----------- > -- > 2 files changed, 60 insertions(+), 74 deletions(-) [...]
I just tested the v2 patch against latest kernel. Please note that yesterday patch was on a kernel named 5.10.0-rc6+, while today's patch is on a kernel named 5.10.0-rc7+. Even with the latest kernel updates, the patch apply correctly and machine boots normally, fixing the problem. $ uname -a Linux titanium4 5.10.0-rc7+ #3 Tue Dec 8 09:11:20 CET 2020 ppc GNU/Linux $ grep VMAP /boot/config-5.10.0-rc7+ CONFIG_HAVE_ARCH_VMAP_STACK=y CONFIG_VMAP_STACK=y Thank you again. Bye, Giuseppe