From: Alexander Gordeev agordeev@linux.ibm.com
[ Upstream commit 639886b71ddef085a0e7bb1f225b8ae3eda5c06f ]
Commit ada1da31ce34 ("s390/sclp: sort out physical vs virtual pointers usage") fixed the notion of virtual address for sclp_early_sccb pointer. However, it did not take into account that kasan_early_init() can also output messages and sclp_early_sccb should be adjusted by the time kasan_early_init() is called.
Currently it is not a problem, since virtual and physical addresses on s390 are the same. Nevertheless, should they ever differ, this would cause an invalid pointer access.
Fixes: ada1da31ce34 ("s390/sclp: sort out physical vs virtual pointers usage") Reviewed-by: Heiko Carstens hca@linux.ibm.com Signed-off-by: Alexander Gordeev agordeev@linux.ibm.com Signed-off-by: Heiko Carstens hca@linux.ibm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/s390/kernel/early.c | 1 - arch/s390/kernel/head64.S | 1 + drivers/s390/char/sclp_early.c | 2 +- 3 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c index 6030fdd6997bc..9693c8630e73f 100644 --- a/arch/s390/kernel/early.c +++ b/arch/s390/kernel/early.c @@ -288,7 +288,6 @@ static void __init sort_amode31_extable(void)
void __init startup_init(void) { - sclp_early_adjust_va(); reset_tod_clock(); check_image_bootable(); time_early_init(); diff --git a/arch/s390/kernel/head64.S b/arch/s390/kernel/head64.S index d7b8b6ad574dc..3b3bf8329e6c1 100644 --- a/arch/s390/kernel/head64.S +++ b/arch/s390/kernel/head64.S @@ -25,6 +25,7 @@ ENTRY(startup_continue) larl %r14,init_task stg %r14,__LC_CURRENT larl %r15,init_thread_union+THREAD_SIZE-STACK_FRAME_OVERHEAD-__PT_SIZE + brasl %r14,sclp_early_adjust_va # allow sclp_early_printk #ifdef CONFIG_KASAN brasl %r14,kasan_early_init #endif diff --git a/drivers/s390/char/sclp_early.c b/drivers/s390/char/sclp_early.c index d15b0d541de36..140d4ee29105c 100644 --- a/drivers/s390/char/sclp_early.c +++ b/drivers/s390/char/sclp_early.c @@ -161,7 +161,7 @@ static void __init sclp_early_console_detect(struct init_sccb *sccb) sclp.has_linemode = 1; }
-void __init sclp_early_adjust_va(void) +void __init __no_sanitize_address sclp_early_adjust_va(void) { sclp_early_sccb = __va((unsigned long)sclp_early_sccb); }