linux-kernel - [PATCH v2] x86/efi: earlyprintk - Add 64bit efi fb address support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 13 Sep 2018 02:00:08 +0800
From:   Aaron Ma <aaron.ma@...onical.com>
To:     ard.biesheuvel@...aro.org, tglx@...utronix.de, x86@...nel.org,
        linux-efi@...r.kernel.org, linux-kernel@...r.kernel.org,
        aaron.ma@...onical.com
Subject: [PATCH v2] x86/efi: earlyprintk - Add 64bit efi fb address support

EFI GOP uses 64-bit frame buffer address in some BIOS.
Add 64bit address support in efi earlyprintk.

V2:
Fix type of address.

Signed-off-by: Aaron Ma <aaron.ma@...onical.com>
---
 arch/x86/platform/efi/early_printk.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/x86/platform/efi/early_printk.c b/arch/x86/platform/efi/early_printk.c
index 5fdacb322ceb..7476b3b097e1 100644
--- a/arch/x86/platform/efi/early_printk.c
+++ b/arch/x86/platform/efi/early_printk.c
@@ -26,12 +26,14 @@ static bool early_efi_keep;
  */
 static __init int early_efi_map_fb(void)
 {
-	unsigned long base, size;
+	u64 base, size;
 
 	if (!early_efi_keep)
 		return 0;
 
 	base = boot_params.screen_info.lfb_base;
+	if (boot_params.screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
+		base |= (u64)boot_params.screen_info.ext_lfb_base << 32;
 	size = boot_params.screen_info.lfb_size;
 	efi_fb = ioremap(base, size);
 
@@ -46,9 +48,11 @@ early_initcall(early_efi_map_fb);
  */
 static __ref void *early_efi_map(unsigned long start, unsigned long len)
 {
-	unsigned long base;
+	u64 base;
 
 	base = boot_params.screen_info.lfb_base;
+	if (boot_params.screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
+		base |= (u64)boot_params.screen_info.ext_lfb_base << 32;
 
 	if (efi_fb)
 		return (efi_fb + start);
-- 
2.17.1