summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorYiFei Zhu <zhuyifei1999@gmail.com>2018-11-29 20:12:30 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-12-21 16:13:12 +0300
commit81710cedad2fa7ea3221cdf77bcb1d39683f07ac (patch)
tree7b70061473789653d367b78d1f3c49cc91239cc2
parent3a2c2aae1bca2e176bcc93f02ce4cc8fe8bda326 (diff)
downloadlinux-81710cedad2fa7ea3221cdf77bcb1d39683f07ac.tar.xz
x86/earlyprintk/efi: Fix infinite loop on some screen widths
[ 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 <zhuyifei1999@gmail.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arend van Spriel <arend.vanspriel@broadcom.com> Cc: Bhupesh Sharma <bhsharma@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Eric Snowberg <eric.snowberg@oracle.com> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Jon Hunter <jonathanh@nvidia.com> Cc: Julien Thierry <julien.thierry@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Nathan Chancellor <natechancellor@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20181129171230.18699-12-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r--arch/x86/platform/efi/early_printk.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/platform/efi/early_printk.c b/arch/x86/platform/efi/early_printk.c
index 5fdacb322ceb..c3e6be110b7d 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;
}