intelfb: Fix oops when changing video mode

Reported by: janis huang (Bugzilla Bug 5747)

Fix the following in intelfb. Not sure what's happening, looks like dinfo->name pointer is invalidated after initialization. Remove intelfb_get_fix, it's not needed and move the majority of the code to the initialization routine.

c03a25b2
*pde = 00000000

Oops: 0000 [#1]
PREEMPT SMP
Modules linked in:
CPU:    0
EIP:    0060:[<c03a25b2>]    Not tainted VLI
EFLAGS: 00010246   (2.6.15-rc5-gcov)

EIP is at intelfb_get_fix+0x35/0x9f
eax: 00000000 ebx: df4fb0a8 ecx: 00000000 edx: df4fb23c
esi: 00000000 edi: df4fb0a8 ebp: df4fb23c esp: df787cbc
ds: 007b es: 007b ss: 0068
Process events/0 (pid: 4, threadinfo=df786000 task=c1524a30)

Stack: dd711824 df4fb23c df4fb008 dd711958 c03a23d9 df4fb0a8 df4fb000 df4fb008
dd711000 df4fb008 c03a2d49 df4fb23c df4fb008 00000000 00000000 df787e44
df4fb008 df787e45 df4fb000 c030217b df4fb000 df787e44 000000a0 00002700
Call Trace:
[<c03a23d9>] update_dinfo+0x6b/0x20f
[<c03a2d49>] intelfb_set_par+0x145/0x30c
[<c030217b>] fb_set_var+0x34e/0x3cf
[<c0169297>] __do_IRQ+0x145/0x1d0
[<c03a340a>] intelfb_imageblit+0x106/0x14b
[<c030109e>] soft_cursor+0x21e/0x2b4
[<c02f5def>] display_to_var+0x2a/0xbf
[<c02fb246>] fbcon_switch+0x1cc/0xd3f
[<c0379887>] redraw_screen+0x1d2/0x3d1
[<c03712e6>] complete_change_console+0x3c/0x1bf
[<c037e169>] console_callback+0x1b0/0x1da
[<c037dfb9>] console_callback+0x0/0x1da
[<c014b898>] worker_thread+0x2c5/0x3c9
[<c0127b1a>] default_wake_function+0x0/0x23
[<c0127b1a>] default_wake_function+0x0/0x23
[<c014b5d3>] worker_thread+0x0/0x3c9
[<c0153200>] kthread+0x12e/0x190
[<c01530d2>] kthread+0x0/0x190
[<c0101dc1>] kernel_thread_helper+0x5/0xb
Code: 8c c0 01 8b 44 24 18 8b 5c 24 14 83 15 8c ea 8c c0 00 8b 90 34 02 00 00

31 c0 b9 11 00
00 00 89 df f3 ab 8b b2 28 0a 00 00 89 df <ac> aa 84 c0 75 fa 8b 82 8c 09 00 00 89 43 10 8b 82 98 09 00 00

---
 intelfbdrv.c |   42 +++++++++++++-----------------------------
 1 files changed, 13 insertions(+), 29 deletions(-)

index ac8d661..0090544 100644
@@ -135,9 +135,6 @@
 static void __devinit get_initial_mode(struct intelfb_info *dinfo);
 static void update_dinfo(struct intelfb_info *dinfo,
 			 struct fb_var_screeninfo *var);
-static int intelfb_get_fix(struct fb_fix_screeninfo *fix,
-			   struct fb_info *info);
-
 static int intelfb_check_var(struct fb_var_screeninfo *var,
 			     struct fb_info *info);
 static int intelfb_set_par(struct fb_info *info);

@@ -1096,7 +1093,17 @@ intelfb_set_fbinfo(struct intelfb_info *
 		return 1;
 
 	info->pixmap.scan_align = 1;
-
+	strcpy(info->fix.id, dinfo->name);
+	info->fix.smem_start = dinfo->fb.physical;
+	info->fix.smem_len = dinfo->fb.size;
+	info->fix.type = FB_TYPE_PACKED_PIXELS;
+	info->fix.type_aux = 0;
+	info->fix.xpanstep = 8;
+	info->fix.ypanstep = 1;
+	info->fix.ywrapstep = 0;
+	info->fix.mmio_start = dinfo->mmio_base_phys;
+	info->fix.mmio_len = INTEL_REG_SIZE;
+	info->fix.accel = FB_ACCEL_I830;
 	update_dinfo(dinfo, &info->var);
 
 	return 0;

@@ -1114,7 +1121,8 @@ update_dinfo(struct intelfb_info *dinfo,
 	dinfo->yres = var->xres;
 	dinfo->pixclock = var->pixclock;
 
-	intelfb_get_fix(&dinfo->info->fix, dinfo->info);
+	dinfo->info->fix.visual = dinfo->visual;
+	dinfo->info->fix.line_length = dinfo->pitch;
 
 	switch (dinfo->bpp) {
 	case 8:

@@ -1144,30 +1152,6 @@ update_dinfo(struct intelfb_info *dinfo,
 
 /* fbops functions */
 
-static int
-intelfb_get_fix(struct fb_fix_screeninfo *fix, struct fb_info *info)
-{
-	struct intelfb_info *dinfo = GET_DINFO(info);
-
-	DBG_MSG("intelfb_get_fix\n");
-
-	memset(fix, 0, sizeof(*fix));
-	strcpy(fix->id, dinfo->name);
-	fix->smem_start = dinfo->fb.physical;
-	fix->smem_len = dinfo->fb.size;
-	fix->type = FB_TYPE_PACKED_PIXELS;
-	fix->type_aux = 0;
-	fix->visual = dinfo->visual;
-	fix->xpanstep = 8;
-	fix->ypanstep = 1;
-	fix->ywrapstep = 0;
-	fix->line_length = dinfo->pitch;
-	fix->mmio_start = dinfo->mmio_base_phys;
-	fix->mmio_len = INTEL_REG_SIZE;
-	fix->accel = FB_ACCEL_I830;
-	return 0;
-}
-
 /***************************************************************
  *                       fbdev interface                       *
  ***************************************************************/

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