use irq-safe version of llist operations between USB callback and main
diff --git a/firmware/src_simtrace/host_communication.c b/firmware/src_simtrace/host_communication.c
index c06c140..dde5403 100644
--- a/firmware/src_simtrace/host_communication.c
+++ b/firmware/src_simtrace/host_communication.c
@@ -5,6 +5,7 @@
#include "board.h"
#include "req_ctx.h"
#include "linuxlist.h"
+#include "llist_irqsafe.h"
static volatile uint32_t usbep_in_progress[BOARD_USB_NUMENDPOINTS];
@@ -90,7 +91,7 @@
}
rctx->tot_len = transferred;
req_ctx_set_state(rctx, RCTX_S_MAIN_PROCESSING);
- llist_add_tail(&rctx->list, queue);
+ llist_add_tail_irqsafe(&rctx->list, queue);
}
int usb_refill_from_host(struct llist_head *queue, int ep)
diff --git a/firmware/src_simtrace/llist_irqsafe.h b/firmware/src_simtrace/llist_irqsafe.h
new file mode 100644
index 0000000..b466939
--- /dev/null
+++ b/firmware/src_simtrace/llist_irqsafe.h
@@ -0,0 +1,27 @@
+#pragma once
+
+#include "linuxlist.h"
+
+static inline void llist_add_tail_irqsafe(struct llist_head *_new,
+ struct llist_head *head)
+{
+ __disable_irq();
+ llist_add_tail(_new, head);
+ __enable_irq();
+}
+
+static inline struct llist_head *llist_head_dequeue_irqsafe(struct llist_head *head)
+{
+ struct llist_head *lh;
+
+ __disable_irq();
+ if (llist_empty(head)) {
+ lh = NULL;
+ } else {
+ lh = head->next;
+ llist_del(lh);
+ }
+ __enable_irq();
+
+ return lh;
+}
diff --git a/firmware/src_simtrace/mode_cardemu.c b/firmware/src_simtrace/mode_cardemu.c
index e51e990..a26abe7 100644
--- a/firmware/src_simtrace/mode_cardemu.c
+++ b/firmware/src_simtrace/mode_cardemu.c
@@ -7,6 +7,7 @@
#include "iso7816_fidi.h"
#include "utils.h"
#include "linuxlist.h"
+#include "llist_irqsafe.h"
#include "req_ctx.h"
#include "cardemu_prot.h"
@@ -326,12 +327,22 @@
/* iterate over the queue of incoming USB commands and dispatch/execute
* them */
-static void process_any_usb_commands(struct llist_head *main_q, struct cardem_inst *ci)
+static void process_any_usb_commands(struct llist_head *main_q,
+ struct cardem_inst *ci)
{
- struct req_ctx *rctx, *tmp;
+ struct llist_head *lh;
+ struct req_ctx *rctx;
+ int i;
- llist_for_each_entry_safe(rctx, tmp, main_q, list) {
- llist_del(&rctx->list);
+ /* limit the number of iterations to 10, to ensure we don't get
+ * stuck here without returning to main loop processing */
+ for (i = 0; i < 10; i++) {
+ /* de-queue the list head in an irq-safe way */
+ lh = llist_head_dequeue_irqsafe(main_q);
+ if (!lh)
+ break;
+ rctx = llist_entry(lh, struct req_ctx, list);
+ /* dispatch the command with interrupts enabled */
dispatch_usb_command(rctx, ci);
}
}