The patch titled
drivers/char/vt.c: fix vc->vc_origin on take_over_console()
has been added to the -mm tree. Its filename is
fix-vc-vc_origin-on-take_over_console.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: drivers/char/vt.c: fix vc->vc_origin on take_over_console()
From: qiaochong <qiaochong@xxxxxxxxxxx>
kernel will die on some platform when switch from vga mode to framebuffer
mode. The reason of this bug is that bind_con_driver reset vc->vc_origin
to (unsigned long)vc->vc_screenbuf.
On vgacon vc->vc_origin is not releated to vc->vc_screenbuf,if set
vc->vc_origin to vc->vc_screenbuf,kernel will die on vc_do_resize.
static int vc_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,
struct vc_data *vc, unsigned int cols, unsigned int lines)
{
unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
unsigned int old_cols, old_rows, old_row_size, old_screen_size;
unsigned int new_cols, new_rows, new_row_size, new_screen_size;
unsigned int end, user;
...
end = (old_rows > new_rows) ? old_origin +
(old_row_size * new_rows) :
vc->vc_scr_end;
...
/*
here for a test from vgacon to framebuffer:
old_origin=0x810814a0,end=0xb00b8fa0,vc->vc_origin=0x810814a0
the code bellow will copy memory from 0x810814a0 to 0xb00b8fa0,
this will cover kernel code,kernel died here.
*/
while (old_origin < end) {
scr_memcpyw((unsigned short *) new_origin,
(unsigned short *) old_origin, rlth);
if (rrem)
scr_memsetw((void *)(new_origin + rlth),
vc->vc_video_erase_char, rrem);
old_origin += old_row_size;
new_origin += new_row_size;
}
...
}
Signed-off-by: qiaochong <qiaochong@xxxxxxxxxxx>
Cc: Greg KH <greg@xxxxxxxxx>
Cc: Alan Cox <alan@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/char/vt.c | 1 +
1 file changed, 1 insertion(+)
diff -puN drivers/char/vt.c~fix-vc-vc_origin-on-take_over_console drivers/char/vt.c
--- a/drivers/char/vt.c~fix-vc-vc_origin-on-take_over_console
+++ a/drivers/char/vt.c
@@ -3059,6 +3059,7 @@ static int bind_con_driver(const struct
old_was_color = vc->vc_can_do_color;
vc->vc_sw->con_deinit(vc);
+ if(!vc->vc_origin)
vc->vc_origin = (unsigned long)vc->vc_screenbuf;
visual_init(vc, i, 0);
set_origin(vc);
_
Patches currently in -mm which might be from qiaochong@xxxxxxxxxxx are
fix-vc-vc_origin-on-take_over_console.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
