The KCOV handler __sanitizer_cov_trace_pc() uses the PACA, so initialise
the PACA first. This fixes a hang during boot when KASAN and KCOV are
both enabled, where the coverage tracer in kasan_early_init() tries to
access a field of the (currently null) PACA.
Signed-off-by: Benjamin Gray <bg...@linux.ibm.com>
---
I tried annotating kasan_early_init() with 'notrace', but it still
seemed to hang. It would also be less robust, because kasan_early_init()
may in future call generic code that should keep coverage.
---
arch/powerpc/kernel/head_64.S | 3 ---
arch/powerpc/kernel/setup_64.c | 4 ++++
2 files changed, 4 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index f132d8704263..21a78a849ca8 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -1004,9 +1004,6 @@ start_here_multiplatform:
* and SLB setup before we turn on relocation.
*/
-#ifdef CONFIG_KASAN
- bl CFUNC(kasan_early_init)
-#endif
/* Restore parameters passed from prom_init/kexec */
mr r3,r31
LOAD_REG_ADDR(r12, DOTSYM(early_setup))
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 246201d0d879..a3f5decbc041 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -369,6 +369,10 @@ void __init early_setup(unsigned long dt_ptr)
/* -------- printk is now safe to use ------- */
+#ifdef CONFIG_KASAN
+ kasan_early_init();
+#endif
+
if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && (mfmsr() & MSR_HV))
enable_machine_check();
--
2.41.0
