2008-11-16 10:52:55

by Bruno Prémont

[permalink] [raw]
Subject: [PATCH] viafb: fix releasing of /proc/viafb/ subtree

When unloading viafb module it does not remove it's /proc/viafb/
subtree which causes multiple viafb directories to appear below
proc when mobprobing viafb and also lets kernel WARN() on duplicate
proc entries:

[ 145.458387] WARNING: at /usr/src/linux-2.6.28-rc3-git6/fs/proc/generic.c:551 proc_register+0xe6/0x160()
[ 145.458945] proc_dir_entry '/proc/viafb' already registered
[ 145.459278] Modules linked in: viafb(+) i2c_algo_bit cfbcopyarea cfbimgblt cfbfillrect snd_hda_intel snd_pcm snd_timer snd soundcore snd_page_alloc sg via_agp agpgart [last unloaded: drm]
[ 145.460647] Pid: 1904, comm: modprobe Tainted: G W 2.6.28-rc3-git6 #4
[ 145.461064] Call Trace:
[ 145.461248] [<c01066f1>] ? dump_stack+0x1/0x80
[ 145.461533] [<c01228a3>] warn_slowpath+0x63/0x80
[ 145.461851] [<c0253ec9>] ? idr_get_empty_slot+0xe9/0x250
[ 145.462186] [<c0254120>] ? ida_get_new_above+0xf0/0x150
[ 145.462528] [<c019fb86>] proc_register+0xe6/0x160
[ 145.462827] [<c019fdc6>] proc_mkdir_mode+0x36/0x50
[ 145.463135] [<c019fdef>] proc_mkdir+0xf/0x20
[ 145.463457] [<f807173c>] viafb_init+0x73c/0xc86 [viafb]
[ 145.463823] [<f8071000>] ? viafb_init+0x0/0xc86 [viafb]
[ 145.464147] [<c010111d>] do_one_initcall+0x2d/0x160
[ 145.464460] [<c01a6543>] ? sysfs_add_file+0x13/0x20
[ 145.464786] [<c015f031>] ? vfree+0x21/0x30
[ 145.465049] [<c01433b5>] ? load_module+0x1215/0x1500
[ 145.465381] [<c014e455>] ? __alloc_pages_internal+0x95/0x400
[ 145.465755] [<c0143723>] sys_init_module+0x83/0x1a0
[ 145.466065] [<c016ceed>] ? sys_read+0x3d/0x70
[ 145.466354] [<c0103bc1>] sysenter_do_call+0x12/0x25
[ 145.466653] ---[ end trace c84b37826e16748c ]---

Signed-off-by: Bruno Prémont <[email protected]>
---
--- linux-2.6.28-rc3-git6.orig/drivers/video/via/viafbdev.c 2008-11-09 19:36:47.000000000 +0100
+++ linux-2.6.28-rc3-git6/drivers/video/via/viafbdev.c 2008-11-16 00:20:10.000000000 +0100
@@ -2036,30 +2036,30 @@ static int viafb_vt1636_proc_write(struc
return count;
}

-static void viafb_init_proc(struct proc_dir_entry *viafb_entry)
+static void viafb_init_proc(struct proc_dir_entry **viafb_entry)
{
struct proc_dir_entry *entry;
- viafb_entry = proc_mkdir("viafb", NULL);
+ *viafb_entry = proc_mkdir("viafb", NULL);
if (viafb_entry) {
- entry = create_proc_entry("dvp0", 0, viafb_entry);
+ entry = create_proc_entry("dvp0", 0, *viafb_entry);
if (entry) {
entry->owner = THIS_MODULE;
entry->read_proc = viafb_dvp0_proc_read;
entry->write_proc = viafb_dvp0_proc_write;
}
- entry = create_proc_entry("dvp1", 0, viafb_entry);
+ entry = create_proc_entry("dvp1", 0, *viafb_entry);
if (entry) {
entry->owner = THIS_MODULE;
entry->read_proc = viafb_dvp1_proc_read;
entry->write_proc = viafb_dvp1_proc_write;
}
- entry = create_proc_entry("dfph", 0, viafb_entry);
+ entry = create_proc_entry("dfph", 0, *viafb_entry);
if (entry) {
entry->owner = THIS_MODULE;
entry->read_proc = viafb_dfph_proc_read;
entry->write_proc = viafb_dfph_proc_write;
}
- entry = create_proc_entry("dfpl", 0, viafb_entry);
+ entry = create_proc_entry("dfpl", 0, *viafb_entry);
if (entry) {
entry->owner = THIS_MODULE;
entry->read_proc = viafb_dfpl_proc_read;
@@ -2068,7 +2068,7 @@ static void viafb_init_proc(struct proc_
if (VT1636_LVDS == viaparinfo->chip_info->lvds_chip_info.
lvds_chip_name || VT1636_LVDS ==
viaparinfo->chip_info->lvds_chip_info2.lvds_chip_name) {
- entry = create_proc_entry("vt1636", 0, viafb_entry);
+ entry = create_proc_entry("vt1636", 0, *viafb_entry);
if (entry) {
entry->owner = THIS_MODULE;
entry->read_proc = viafb_vt1636_proc_read;
@@ -2087,6 +2087,7 @@ static void viafb_remove_proc(struct pro
remove_proc_entry("dfpl", viafb_entry);
remove_proc_entry("vt1636", viafb_entry);
remove_proc_entry("vt1625", viafb_entry);
+ remove_proc_entry("viafb", NULL);
}

static int __devinit via_pci_probe(void)
@@ -2348,7 +2349,7 @@ static int __devinit via_pci_probe(void)
viafbinfo->node, viafbinfo->fix.id, default_var.xres,
default_var.yres, default_var.bits_per_pixel);

- viafb_init_proc(viaparinfo->proc_entry);
+ viafb_init_proc(&viaparinfo->proc_entry);
viafb_init_dac(IGA2);
return 0;
}