summaryrefslogtreecommitdiff
path: root/arch/arc/kernel/stacktrace.c
diff options
context:
space:
mode:
authorMark Brown <broonie@kernel.org>2020-12-10 13:30:11 +0000
committerMark Brown <broonie@kernel.org>2020-12-10 13:30:11 +0000
commit49ab19a4a51a31cb06992386cec4be82ebca5a2d (patch)
treede7d31ec7ded2c8ab8dbdfe5a55fa283068023d0 /arch/arc/kernel/stacktrace.c
parentb0dfd948379c79b8754e224e29b99d30ce0d79b8 (diff)
parent3b25f337929e73232f0aa990cd68a129f53652e2 (diff)
downloadlwn-49ab19a4a51a31cb06992386cec4be82ebca5a2d.tar.gz
lwn-49ab19a4a51a31cb06992386cec4be82ebca5a2d.zip
Merge series "spi: spi-geni-qcom: Use gpio descriptors for CS" from Stephen Boyd <swboyd@chromium.org>:
Collected patches from the two series below and associated tags so they can be merged in one pile through the spi tree. Merry December! SPI: https://lore.kernel.org/r/20201202214935.1114381-1-swboyd@chromium.org cros-ec: https://lore.kernel.org/r/20201203011649.1405292-1-swboyd@chromium.org Cc: Akash Asthana <akashast@codeaurora.org> Cc: Simon Glass <sjg@chromium.org> Cc: Gwendal Grignou <gwendal@chromium.org> Cc: Douglas Anderson <dianders@chromium.org> Cc: Alexandru M Stan <amstan@chromium.org> Stephen Boyd (3): platform/chrome: cros_ec_spi: Don't overwrite spi::mode platform/chrome: cros_ec_spi: Drop bits_per_word assignment spi: spi-geni-qcom: Use the new method of gpio CS control drivers/platform/chrome/cros_ec_spi.c | 2 -- drivers/spi/spi-geni-qcom.c | 1 + 2 files changed, 1 insertion(+), 2 deletions(-) base-commit: b65054597872ce3aefbc6a666385eabdf9e288da -- https://chromeos.dev
Diffstat (limited to 'arch/arc/kernel/stacktrace.c')
-rw-r--r--arch/arc/kernel/stacktrace.c63
1 files changed, 37 insertions, 26 deletions
diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c
index feba91c9d969..f73da203b170 100644
--- a/arch/arc/kernel/stacktrace.c
+++ b/arch/arc/kernel/stacktrace.c
@@ -38,15 +38,27 @@
#ifdef CONFIG_ARC_DW2_UNWIND
-static void seed_unwind_frame_info(struct task_struct *tsk,
- struct pt_regs *regs,
- struct unwind_frame_info *frame_info)
+static int
+seed_unwind_frame_info(struct task_struct *tsk, struct pt_regs *regs,
+ struct unwind_frame_info *frame_info)
{
- /*
- * synchronous unwinding (e.g. dump_stack)
- * - uses current values of SP and friends
- */
- if (tsk == NULL && regs == NULL) {
+ if (regs) {
+ /*
+ * Asynchronous unwinding of intr/exception
+ * - Just uses the pt_regs passed
+ */
+ frame_info->task = tsk;
+
+ frame_info->regs.r27 = regs->fp;
+ frame_info->regs.r28 = regs->sp;
+ frame_info->regs.r31 = regs->blink;
+ frame_info->regs.r63 = regs->ret;
+ frame_info->call_frame = 0;
+ } else if (tsk == NULL || tsk == current) {
+ /*
+ * synchronous unwinding (e.g. dump_stack)
+ * - uses current values of SP and friends
+ */
unsigned long fp, sp, blink, ret;
frame_info->task = current;
@@ -63,13 +75,17 @@ static void seed_unwind_frame_info(struct task_struct *tsk,
frame_info->regs.r31 = blink;
frame_info->regs.r63 = ret;
frame_info->call_frame = 0;
- } else if (regs == NULL) {
+ } else {
/*
- * Asynchronous unwinding of sleeping task
- * - Gets SP etc from task's pt_regs (saved bottom of kernel
- * mode stack of task)
+ * Asynchronous unwinding of a likely sleeping task
+ * - first ensure it is actually sleeping
+ * - if so, it will be in __switch_to, kernel mode SP of task
+ * is safe-kept and BLINK at a well known location in there
*/
+ if (tsk->state == TASK_RUNNING)
+ return -1;
+
frame_info->task = tsk;
frame_info->regs.r27 = TSK_K_FP(tsk);
@@ -90,19 +106,8 @@ static void seed_unwind_frame_info(struct task_struct *tsk,
frame_info->regs.r28 += 60;
frame_info->call_frame = 0;
- } else {
- /*
- * Asynchronous unwinding of intr/exception
- * - Just uses the pt_regs passed
- */
- frame_info->task = tsk;
-
- frame_info->regs.r27 = regs->fp;
- frame_info->regs.r28 = regs->sp;
- frame_info->regs.r31 = regs->blink;
- frame_info->regs.r63 = regs->ret;
- frame_info->call_frame = 0;
}
+ return 0;
}
#endif
@@ -112,11 +117,12 @@ arc_unwind_core(struct task_struct *tsk, struct pt_regs *regs,
int (*consumer_fn) (unsigned int, void *), void *arg)
{
#ifdef CONFIG_ARC_DW2_UNWIND
- int ret = 0;
+ int ret = 0, cnt = 0;
unsigned int address;
struct unwind_frame_info frame_info;
- seed_unwind_frame_info(tsk, regs, &frame_info);
+ if (seed_unwind_frame_info(tsk, regs, &frame_info))
+ return 0;
while (1) {
address = UNW_PC(&frame_info);
@@ -132,6 +138,11 @@ arc_unwind_core(struct task_struct *tsk, struct pt_regs *regs,
break;
frame_info.regs.r63 = frame_info.regs.r31;
+
+ if (cnt++ > 128) {
+ printk("unwinder looping too long, aborting !\n");
+ return 0;
+ }
}
return address; /* return the last address it saw */