From b3a3ac0f6b46feb2ff6abf4deba9a7395aed2575 Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Fri, 6 Mar 2009 14:28:27 +0000 Subject: [PATCH] Do not deadlock in scheduler when sending VIRQ_CON_RING. Instead defer the virq notification to tasklet context. Signed-off-by: Keir Fraser --- xen/drivers/char/console.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c index 3096b3ec9d..00a32022dd 100644 --- a/xen/drivers/char/console.c +++ b/xen/drivers/char/console.c @@ -315,6 +315,12 @@ static void serial_rx(char c, struct cpu_user_regs *regs) __serial_rx(c, regs); } +static void notify_dom0_con_ring(unsigned long unused) +{ + send_guest_global_virq(dom0, VIRQ_CON_RING); +} +static DECLARE_TASKLET(notify_dom0_con_ring_tasklet, notify_dom0_con_ring, 0); + static long guest_console_write(XEN_GUEST_HANDLE(char) buffer, int count) { char kbuf[128], *kptr; @@ -348,7 +354,7 @@ static long guest_console_write(XEN_GUEST_HANDLE(char) buffer, int count) { for ( kptr = kbuf; *kptr != '\0'; kptr++ ) putchar_console_ring(*kptr); - send_guest_global_virq(dom0, VIRQ_CON_RING); + tasklet_schedule(¬ify_dom0_con_ring_tasklet); } spin_unlock_irq(&console_lock); @@ -426,7 +432,7 @@ static void __putstr(const char *str) while ( (c = *str++) != '\0' ) putchar_console_ring(c); - send_guest_global_virq(dom0, VIRQ_CON_RING); + tasklet_schedule(¬ify_dom0_con_ring_tasklet); } static int printk_prefix_check(char *p, char **pp) -- 2.30.2