From 13ebb50d2789de7bd47cebe57e3f6eba58fdcc7e Mon Sep 17 00:00:00 2001 From: Gabor Juhos Date: Fri, 19 Jul 2013 08:43:35 +0200 Subject: [PATCH 1/2] early: keep stdio files open At the end of the 'early_console' function, the file descriptor is closed unconditionally. This 'close' call closes the stdio files if the fd returned by the 'open(dev/console)' call equals with any of the STD{IN,OUT,ERR}_FILENO values. When this happens, all subsequent accesses to the stdio files will fail and early console access won't work. To avoid this, don't close the file descriptor if that equals with any of the STD*_FILENO values. Signed-off-by: Gabor Juhos --- Note: The issue happens if Linux is unable to open the initial console before calling init. In this case, the 'open(dev/console)' call in the 'early_console' function returns with zero. --- early.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/early.c b/early.c index 27d0929..204623b 100644 --- a/early.c +++ b/early.c @@ -65,7 +65,11 @@ static void early_console(const char *dev) dup2(dd, STDIN_FILENO); dup2(dd, STDOUT_FILENO); dup2(dd, STDERR_FILENO); - close(dd); + + if (dd != STDIN_FILENO && + dd != STDOUT_FILENO && + dd != STDERR_FILENO) + close(dd); } static void early_env(void) -- 1.7.10