Commit-ID: 79c2206d369b87b19ac29cb47601059b6bf5c291 Gitweb: https://git.kernel.org/tip/79c2206d369b87b19ac29cb47601059b6bf5c291 Author: YiFei Zhu <[email protected]> AuthorDate: Thu, 29 Nov 2018 18:12:30 +0100 Committer: Ingo Molnar <[email protected]> CommitDate: Fri, 30 Nov 2018 09:05:13 +0100
x86/earlyprintk/efi: Fix infinite loop on some screen widths 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]> --- 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 7476b3b097e1..7138bc7a265c 100644 --- a/arch/x86/platform/efi/early_printk.c +++ b/arch/x86/platform/efi/early_printk.c @@ -183,7 +183,7 @@ 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; }
