From: Sven Schnelle svens@linux.ibm.com
[ Upstream commit 436fc4feeabbf103d78d50a8e091b3aac28cc37f ]
kmemleak with enabled auto scanning reports that our stack allocation is lost. This is because we're saving the pointer + STACK_INIT_OFFSET to lowcore. When kmemleak now scans the objects, it thinks that this one is lost because it can't find a corresponding pointer.
Reported-by: Marc Hartmayer mhartmay@linux.ibm.com Signed-off-by: Sven Schnelle svens@linux.ibm.com Tested-by: Marc Hartmayer mhartmay@linux.ibm.com Signed-off-by: Heiko Carstens hca@linux.ibm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/s390/kernel/setup.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index ff0f9e838916..08c2263271e3 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -50,6 +50,7 @@ #include <linux/compat.h> #include <linux/start_kernel.h> #include <linux/hugetlb.h> +#include <linux/kmemleak.h>
#include <asm/boot_data.h> #include <asm/ipl.h> @@ -312,9 +313,12 @@ void *restart_stack; unsigned long stack_alloc(void) { #ifdef CONFIG_VMAP_STACK - return (unsigned long)__vmalloc_node(THREAD_SIZE, THREAD_SIZE, - THREADINFO_GFP, NUMA_NO_NODE, - __builtin_return_address(0)); + void *ret; + + ret = __vmalloc_node(THREAD_SIZE, THREAD_SIZE, THREADINFO_GFP, + NUMA_NO_NODE, __builtin_return_address(0)); + kmemleak_not_leak(ret); + return (unsigned long)ret; #else return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER); #endif