Merge tag 'v5.2-rc4' into media/master

There are some conflicts due to SPDX changes. We also have more
patches being merged via media tree touching them.

So, let's merge back from upstream and address those.

Linux 5.2-rc4

* tag 'v5.2-rc4': (767 commits)
  Linux 5.2-rc4
  MAINTAINERS: Karthikeyan Ramasubramanian is MIA
  i2c: xiic: Add max_read_len quirk
  lockref: Limit number of cmpxchg loop retries
  uaccess: add noop untagged_addr definition
  x86/insn-eval: Fix use-after-free access to LDT entry
  kbuild: use more portable 'command -v' for cc-cross-prefix
  s390/unwind: correct stack switching during unwind
  block, bfq: add weight symlink to the bfq.weight cgroup parameter
  cgroup: let a symlink too be created with a cftype file
  drm/nouveau/secboot/gp10[2467]: support newer FW to fix SEC2 failures on some boards
  drm/nouveau/secboot: enable loading of versioned LS PMU/SEC2 ACR msgqueue FW
  drm/nouveau/secboot: split out FW version-specific LS function pointers
  drm/nouveau/secboot: pass max supported FW version to LS load funcs
  drm/nouveau/core: support versioned firmware loading
  drm/nouveau/core: pass subdev into nvkm_firmware_get, rather than device
  block: free sched's request pool in blk_cleanup_queue
  pktgen: do not sleep with the thread lock held.
  net: mvpp2: Use strscpy to handle stat strings
  net: rds: fix memory leak in rds_ib_flush_mr_pool
  ...

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

1 files changed, 17 insertions, 6 deletions

diff --git a/drivers/misc/lkdtm/bugs.c b/drivers/misc/lkdtm/bugs.c
index 7eebbdfbcacd..17f839dee976 100644
--- a/drivers/misc/lkdtm/bugs.c
+++ b/drivers/misc/lkdtm/bugs.c
@@ -32,12 +32,20 @@ static int recur_count = REC_NUM_DEFAULT;
 
 static DEFINE_SPINLOCK(lock_me_up);
 
-static int recursive_loop(int remaining)
+/*
+ * Make sure compiler does not optimize this function or stack frame away:
+ * - function marked noinline
+ * - stack variables are marked volatile
+ * - stack variables are written (memset()) and read (pr_info())
+ * - function has external effects (pr_info())
+ * */
+static int noinline recursive_loop(int remaining)
 {
-	char buf[REC_STACK_SIZE];
+	volatile char buf[REC_STACK_SIZE];
 
-	/* Make sure compiler does not optimize this away. */
-	memset(buf, (remaining & 0xff) | 0x1, REC_STACK_SIZE);
+	memset((void *)buf, remaining & 0xFF, sizeof(buf));
+	pr_info("loop %d/%d ...\n", (int)buf[remaining % sizeof(buf)],
+		recur_count);
 	if (!remaining)
 		return 0;
 	else
@@ -81,9 +89,12 @@ void lkdtm_LOOP(void)
 		;
 }
 
-void lkdtm_OVERFLOW(void)
+void lkdtm_EXHAUST_STACK(void)
 {
-	(void) recursive_loop(recur_count);
+	pr_info("Calling function with %d frame size to depth %d ...\n",
+		REC_STACK_SIZE, recur_count);
+	recursive_loop(recur_count);
+	pr_info("FAIL: survived without exhausting stack?!\n");
 }
 
 static noinline void __lkdtm_CORRUPT_STACK(void *stack)