From: H. Peter Anvin To: Linus Torvalds Cc: Linux Kernel Mailing List Bcc: H. Peter Anvin Subject: [GIT PULL] Fix decoding of video mode numbers in acpi/wakeup.S Hi Linus, Please pull: git://git.kernel.org/pub/scm/linux/kernel/git/hpa/linux-2.6-x86setup.git for-linus H. Peter Anvin (2): [x86 setup] Present the canonical video mode number to the kernel [acpi] Correct the decoding of video mode numbers in wakeup.S arch/i386/boot/video.c | 14 ++++++++--- arch/i386/kernel/acpi/wakeup.S | 41 ++++++++------------------------- arch/x86_64/kernel/acpi/wakeup.S | 47 ++++++++++--------------------------- 3 files changed, 33 insertions(+), 69 deletions(-) [Log messages and full diffs follow] commit 5178fb23e3e41500fd066ecd4be15a60dd373e75 Author: H. Peter Anvin Date: Thu Sep 13 14:16:37 2007 -0700 [acpi] Correct the decoding of video mode numbers in wakeup.S wakeup.S looks at the video mode number from the setup header and looks to see if it is a VESA mode. Unfortunately, the decoding is done incorrectly and it will attempt to frob the VESA BIOS for any mode number 0x0200 or larger. Correct this, and remove a bunch of #if 0'd code. Massive thanks to Jeff Chua for reporting the bug, and suffering though a large number of experiments in order to track this problem down. Cc: Pavel Machek Signed-off-by: H. Peter Anvin diff --git a/arch/i386/kernel/acpi/wakeup.S b/arch/i386/kernel/acpi/wakeup.S index ed0a0f2..f22ba85 100644 --- a/arch/i386/kernel/acpi/wakeup.S +++ b/arch/i386/kernel/acpi/wakeup.S @@ -151,51 +151,30 @@ bogus_real_magic: #define VIDEO_FIRST_V7 0x0900 # Setting of user mode (AX=mode ID) => CF=success + +# For now, we only handle VESA modes (0x0200..0x03ff). To handle other +# modes, we should probably compile in the video code from the boot +# directory. mode_set: movw %ax, %bx -#if 0 - cmpb $0xff, %ah - jz setalias - - testb $VIDEO_RECALC>>8, %ah - jnz _setrec - - cmpb $VIDEO_FIRST_RESOLUTION>>8, %ah - jnc setres - - cmpb $VIDEO_FIRST_SPECIAL>>8, %ah - jz setspc - - cmpb $VIDEO_FIRST_V7>>8, %ah - jz setv7 -#endif - - cmpb $VIDEO_FIRST_VESA>>8, %ah - jnc check_vesa -#if 0 - orb %ah, %ah - jz setmenu -#endif - - decb %ah -# jz setbios Add bios modes later + subb $VIDEO_FIRST_VESA>>8, %bh + cmpb $2, %bh + jb check_vesa -setbad: clc +setbad: + clc ret check_vesa: - subb $VIDEO_FIRST_VESA>>8, %bh orw $0x4000, %bx # Use linear frame buffer movw $0x4f02, %ax # VESA BIOS mode set call int $0x10 cmpw $0x004f, %ax # AL=4f if implemented - jnz _setbad # AH=0 if OK + jnz setbad # AH=0 if OK stc ret -_setbad: jmp setbad - .code32 ALIGN diff --git a/arch/x86_64/kernel/acpi/wakeup.S b/arch/x86_64/kernel/acpi/wakeup.S index 13f1480..a06f2bc 100644 --- a/arch/x86_64/kernel/acpi/wakeup.S +++ b/arch/x86_64/kernel/acpi/wakeup.S @@ -81,7 +81,7 @@ wakeup_code: testl $2, realmode_flags - wakeup_code jz 1f mov video_mode - wakeup_code, %ax - call mode_seta + call mode_set 1: movw $0xb800, %ax @@ -291,52 +291,31 @@ no_longmode: #define VIDEO_FIRST_V7 0x0900 # Setting of user mode (AX=mode ID) => CF=success + +# For now, we only handle VESA modes (0x0200..0x03ff). To handle other +# modes, we should probably compile in the video code from the boot +# directory. .code16 -mode_seta: +mode_set: movw %ax, %bx -#if 0 - cmpb $0xff, %ah - jz setalias - - testb $VIDEO_RECALC>>8, %ah - jnz _setrec - - cmpb $VIDEO_FIRST_RESOLUTION>>8, %ah - jnc setres - - cmpb $VIDEO_FIRST_SPECIAL>>8, %ah - jz setspc - - cmpb $VIDEO_FIRST_V7>>8, %ah - jz setv7 -#endif - - cmpb $VIDEO_FIRST_VESA>>8, %ah - jnc check_vesaa -#if 0 - orb %ah, %ah - jz setmenu -#endif - - decb %ah -# jz setbios Add bios modes later + subb $VIDEO_FIRST_VESA>>8, %bh + cmpb $2, %bh + jb check_vesa -setbada: clc +setbad: + clc ret -check_vesaa: - subb $VIDEO_FIRST_VESA>>8, %bh +check_vesa: orw $0x4000, %bx # Use linear frame buffer movw $0x4f02, %ax # VESA BIOS mode set call int $0x10 cmpw $0x004f, %ax # AL=4f if implemented - jnz _setbada # AH=0 if OK + jnz setbad # AH=0 if OK stc ret -_setbada: jmp setbada - wakeup_stack_begin: # Stack grows down .org 0xff0 commit f41b4d086c58ca531ad512e1e9d6712b2310969e Author: H. Peter Anvin Date: Thu Sep 13 14:14:29 2007 -0700 [x86 setup] Present the canonical video mode number to the kernel Canonicalize the video mode number as presented to the kernel. The video mode number may be user-entered (e.g. ASK_VGA), an alias (e.g. NORMAL_VGA), or a size specification, and that confuses the suspend wakeup code. Signed-off-by: H. Peter Anvin diff --git a/arch/i386/boot/video.c b/arch/i386/boot/video.c index 693f20d..e4ba897 100644 --- a/arch/i386/boot/video.c +++ b/arch/i386/boot/video.c @@ -147,7 +147,7 @@ int mode_defined(u16 mode) } /* Set mode (without recalc) */ -static int raw_set_mode(u16 mode) +static int raw_set_mode(u16 mode, u16 *real_mode) { int nmode, i; struct card_info *card; @@ -165,8 +165,10 @@ static int raw_set_mode(u16 mode) if ((mode == nmode && visible) || mode == mi->mode || - mode == (mi->y << 8)+mi->x) + mode == (mi->y << 8)+mi->x) { + *real_mode = mi->mode; return card->set_mode(mi); + } if (visible) nmode++; @@ -178,7 +180,7 @@ static int raw_set_mode(u16 mode) if (mode >= card->xmode_first && mode < card->xmode_first+card->xmode_n) { struct mode_info mix; - mix.mode = mode; + *real_mode = mix.mode = mode; mix.x = mix.y = 0; return card->set_mode(&mix); } @@ -223,6 +225,7 @@ static void vga_recalc_vertical(void) static int set_mode(u16 mode) { int rv; + u16 real_mode; /* Very special mode numbers... */ if (mode == VIDEO_CURRENT_MODE) @@ -232,13 +235,16 @@ static int set_mode(u16 mode) else if (mode == EXTENDED_VGA) mode = VIDEO_8POINT; - rv = raw_set_mode(mode); + rv = raw_set_mode(mode, &real_mode); if (rv) return rv; if (mode & VIDEO_RECALC) vga_recalc_vertical(); + /* Save the canonical mode number for the kernel, not + an alias, size specification or menu position */ + boot_params.hdr.vid_mode = real_mode; return 0; }