From f92afe56a0dcd271cb94e12acf1861d44c3faefd Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Fri, 29 Sep 2006 01:58:52 -0700 Subject: [PATCH] [PATCH] uml: stack consumption reduction Fix some stack abuse in the sysrq t path. Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/drivers/mconsole_kern.c | 15 ++++++++++----- arch/um/drivers/mconsole_user.c | 4 ++++ 2 files changed, 14 insertions(+), 5 deletions(-) diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c index 79610b5..773a134 100644 --- a/arch/um/drivers/mconsole_kern.c +++ b/arch/um/drivers/mconsole_kern.c @@ -598,6 +598,11 @@ out: mconsole_reply(req, err_msg, err, 0); } +struct mconsole_output { + struct list_head list; + struct mc_request *req; +}; + static DEFINE_SPINLOCK(console_lock); static LIST_HEAD(clients); static char console_buf[MCONSOLE_MAX_DATA]; @@ -622,10 +627,10 @@ static void console_write(struct console *console, const char *string, return; list_for_each(ele, &clients){ - struct mconsole_entry *entry; + struct mconsole_output *entry; - entry = list_entry(ele, struct mconsole_entry, list); - mconsole_reply_len(&entry->request, console_buf, + entry = list_entry(ele, struct mconsole_output, list); + mconsole_reply_len(entry->req, console_buf, console_index, 0, 1); } @@ -649,10 +654,10 @@ late_initcall(mc_add_console); static void with_console(struct mc_request *req, void (*proc)(void *), void *arg) { - struct mconsole_entry entry; + struct mconsole_output entry; unsigned long flags; - entry.request = *req; + entry.req = req; list_add(&entry.list, &clients); spin_lock_irqsave(&console_lock, flags); diff --git a/arch/um/drivers/mconsole_user.c b/arch/um/drivers/mconsole_user.c index 5b2f5fe..17068eb 100644 --- a/arch/um/drivers/mconsole_user.c +++ b/arch/um/drivers/mconsole_user.c @@ -131,6 +131,10 @@ int mconsole_get_request(int fd, struct mc_request *req) int mconsole_reply_len(struct mc_request *req, const char *str, int total, int err, int more) { + /* XXX This is a stack consumption problem. It'd be nice to + * make it global and serialize access to it, but there are a + * ton of callers to this function. + */ struct mconsole_reply reply; int len, n; -- 2.7.4