From 2d8d8fac3b4eab035dcd0068e1f5a746a697fbb3 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Wed, 15 May 2019 14:38:06 +0900 Subject: x86/uaccess: Allow access_ok() in irq context if pagefault_disabled WARN_ON_IN_IRQ() assumes that the access_ok() and following user memory access can sleep. But this assumption is not always correct; when the pagefault is disabled, following memory access will just returns -EFAULT and never sleep. Add pagefault_disabled() check in WARN_ON_ONCE() so that it can ignore the case we call it with disabling pagefault. For this purpose, this modified pagefault_disabled() as an inline function. Link: http://lkml.kernel.org/r/155789868664.26965.7932665824135793317.stgit@devnote2 Acked-by: Ingo Molnar Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- include/linux/uaccess.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'include/linux/uaccess.h') diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index 2b70130af585..5a43ef7db492 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -203,7 +203,10 @@ static inline void pagefault_enable(void) /* * Is the pagefault handler disabled? If so, user access methods will not sleep. */ -#define pagefault_disabled() (current->pagefault_disabled != 0) +static inline bool pagefault_disabled(void) +{ + return current->pagefault_disabled != 0; +} /* * The pagefault handler is in general disabled by pagefault_disable() or -- cgit