3.18-stable review patch. If anyone has any objections, please let me know.
------------------ [ Upstream commit 79c2206d369b87b19ac29cb47601059b6bf5c291 ] An affected screen resolution is 1366 x 768, which width is not divisible by 8, the default font width. On such screens, when longer lines are earlyprintk'ed, overflow-to-next-line can never trigger, due to the left-most x-coordinate of the next character always less than the screen width. Earlyprintk will infinite loop in trying to print the rest of the string but unable to, due to the line being full. This patch makes the trigger consider the right-most x-coordinate, instead of left-most, as the value to compare against the screen width threshold. Signed-off-by: YiFei Zhu <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Arend van Spriel <[email protected]> Cc: Bhupesh Sharma <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Eric Snowberg <[email protected]> Cc: Hans de Goede <[email protected]> Cc: Joe Perches <[email protected]> Cc: Jon Hunter <[email protected]> Cc: Julien Thierry <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Marc Zyngier <[email protected]> Cc: Matt Fleming <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Sai Praneeth Prakhya <[email protected]> Cc: Sedat Dilek <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- arch/x86/platform/efi/early_printk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/platform/efi/early_printk.c b/arch/x86/platform/efi/early_printk.c index 524142117296..82324fc25d5e 100644 --- a/arch/x86/platform/efi/early_printk.c +++ b/arch/x86/platform/efi/early_printk.c @@ -179,7 +179,7 @@ early_efi_write(struct console *con, const char *str, unsigned int num) num--; } - if (efi_x >= si->lfb_width) { + if (efi_x + font->width > si->lfb_width) { efi_x = 0; efi_y += font->height; } -- 2.19.1
