flush_icache_range() contains a bodge to avoid issuing IPIs when the kgdb
trap handler is running because issuing IPIs is unsafe (and unnecessary)
in this exection context. However the current test is flawed: it both
over-matches (could skip the IPI when the kgdb trap is not running) and
under-matches (does not skip the IPI for all kgdb cache operations).
Fix by replacing the ad-hoc check with the proper kgdb macro. This also
allows us to drop the #ifdef wrapper.
Fixes: 3b8c9f1cdfc5 ("arm64: IPI each CPU after invalidating the I-cache for
kernel mappings")
Signed-off-by: Daniel Thompson <[email protected]>
---
arch/arm64/include/asm/cacheflush.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/include/asm/cacheflush.h
b/arch/arm64/include/asm/cacheflush.h
index e6cca3d4acf7..ce50c1f1f1ea 100644
--- a/arch/arm64/include/asm/cacheflush.h
+++ b/arch/arm64/include/asm/cacheflush.h
@@ -79,7 +79,7 @@ static inline void flush_icache_range(unsigned long start,
unsigned long end)
* IPI all online CPUs so that they undergo a context synchronization
* event and are forced to refetch the new instructions.
*/
-#ifdef CONFIG_KGDB
+
/*
* KGDB performs cache maintenance with interrupts disabled, so we
* will deadlock trying to IPI the secondary CPUs. In theory, we can
@@ -89,9 +89,9 @@ static inline void flush_icache_range(unsigned long start,
unsigned long end)
* the patching operation, so we don't need extra IPIs here anyway.
* In which case, add a KGDB-specific bodge and return early.
*/
- if (kgdb_connected && irqs_disabled())
+ if (in_dbg_master())
return;
-#endif
+
kick_all_cpus_sync();
}
base-commit: 6a8b55ed4056ea5559ebe4f6a4b247f627870d4c
--
2.25.1
