| Message ID | 20201029101428.4058311-1-daniel.vetter@ffwll.ch (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/3] fbcon: Disable accelerated scrolling | expand |
Hi Daniel,
I love your patch! Perhaps something to improve:
[auto build test WARNING on drm-intel/for-linux-next]
[also build test WARNING on drm-tip/drm-tip drm-exynos/exynos-drm-next tegra-drm/drm/tegra/for-next linus/master drm/drm-next v5.10-rc1 next-20201028]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Daniel-Vetter/fbcon-Disable-accelerated-scrolling/20201029-181618
base: git://anongit.freedesktop.org/drm-intel for-linux-next
config: sparc64-randconfig-r005-20201029 (attached as .config)
compiler: sparc64-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/b457f0ea024ca7202fa63f5a94f9d5abf65529f8
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Daniel-Vetter/fbcon-Disable-accelerated-scrolling/20201029-181618
git checkout b457f0ea024ca7202fa63f5a94f9d5abf65529f8
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sparc64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
drivers/video/fbdev/core/fbcon.c: In function 'fbcon_init':
>> drivers/video/fbdev/core/fbcon.c:1089:6: warning: variable 'cap' set but not used [-Wunused-but-set-variable]
1089 | int cap, ret;
| ^~~
drivers/video/fbdev/core/fbcon.c: In function 'fbcon_exit':
drivers/video/fbdev/core/fbcon.c:3646:7: warning: variable 'pending' set but not used [-Wunused-but-set-variable]
3646 | int pending = 0;
| ^~~~~~~
vim +/cap +1089 drivers/video/fbdev/core/fbcon.c
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1080
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1081 static void fbcon_init(struct vc_data *vc, int init)
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1082 {
1f4ed2fb01f80f drivers/video/fbdev/core/fbcon.c Daniel Vetter 2019-05-28 1083 struct fb_info *info;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1084 struct fbcon_ops *ops;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1085 struct vc_data **default_mode = vc->vc_display_fg;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1086 struct vc_data *svc = *default_mode;
50233393f0cf9b drivers/video/fbdev/core/fbcon.c Daniel Vetter 2019-05-28 1087 struct fbcon_display *t, *p = &fb_display[vc->vc_num];
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1088 int logo = 1, new_rows, new_cols, rows, cols, charcnt = 256;
0fcf6ada2b8eb4 drivers/video/console/fbcon.c Florian Tobias Schandinat 2009-09-22 @1089 int cap, ret;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1090
1f4ed2fb01f80f drivers/video/fbdev/core/fbcon.c Daniel Vetter 2019-05-28 1091 if (WARN_ON(info_idx == -1))
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1092 return;
306958e8e8d150 drivers/video/console/fbcon.c Adrian Bunk 2005-05-01 1093
1f4ed2fb01f80f drivers/video/fbdev/core/fbcon.c Daniel Vetter 2019-05-28 1094 if (con2fb_map[vc->vc_num] == -1)
1f4ed2fb01f80f drivers/video/fbdev/core/fbcon.c Daniel Vetter 2019-05-28 1095 con2fb_map[vc->vc_num] = info_idx;
1f4ed2fb01f80f drivers/video/fbdev/core/fbcon.c Daniel Vetter 2019-05-28 1096
1f4ed2fb01f80f drivers/video/fbdev/core/fbcon.c Daniel Vetter 2019-05-28 1097 info = registered_fb[con2fb_map[vc->vc_num]];
306958e8e8d150 drivers/video/console/fbcon.c Adrian Bunk 2005-05-01 1098 cap = info->flags;
306958e8e8d150 drivers/video/console/fbcon.c Adrian Bunk 2005-05-01 1099
3c5a1b111373e6 drivers/video/fbdev/core/fbcon.c Andreas Schwab 2019-05-06 1100 if (logo_shown < 0 && console_loglevel <= CONSOLE_LOGLEVEL_QUIET)
10993504d64735 drivers/video/fbdev/core/fbcon.c Prarit Bhargava 2019-02-08 1101 logo_shown = FBCON_LOGO_DONTSHOW;
10993504d64735 drivers/video/fbdev/core/fbcon.c Prarit Bhargava 2019-02-08 1102
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1103 if (vc != svc || logo_shown == FBCON_LOGO_DONTSHOW ||
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1104 (info->fix.type == FB_TYPE_TEXT))
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1105 logo = 0;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1106
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1107 if (var_to_display(p, &info->var, info))
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1108 return;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1109
d1baa4ffa677bf drivers/video/console/fbcon.c Antonino A. Daplas 2007-07-17 1110 if (!info->fbcon_par)
d1baa4ffa677bf drivers/video/console/fbcon.c Antonino A. Daplas 2007-07-17 1111 con2fb_acquire_newinfo(vc, info, vc->vc_num, -1);
d1baa4ffa677bf drivers/video/console/fbcon.c Antonino A. Daplas 2007-07-17 1112
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1113 /* If we are not the first console on this
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1114 fb, copy the font from that console */
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1115 t = &fb_display[fg_console];
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1116 if (!p->fontdata) {
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1117 if (t->fontdata) {
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1118 struct vc_data *fvc = vc_cons[fg_console].d;
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1119
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1120 vc->vc_font.data = (void *)(p->fontdata =
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1121 fvc->vc_font.data);
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1122 vc->vc_font.width = fvc->vc_font.width;
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1123 vc->vc_font.height = fvc->vc_font.height;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1124 p->userfont = t->userfont;
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1125
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1126 if (p->userfont)
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1127 REFCOUNT(p->fontdata)++;
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1128 } else {
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1129 const struct font_desc *font = NULL;
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1130
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1131 if (!fontname[0] || !(font = find_font(fontname)))
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1132 font = get_default_font(info->var.xres,
2d2699d9849248 drivers/video/console/fbcon.c Antonino A. Daplas 2007-05-08 1133 info->var.yres,
2d2699d9849248 drivers/video/console/fbcon.c Antonino A. Daplas 2007-05-08 1134 info->pixmap.blit_x,
2d2699d9849248 drivers/video/console/fbcon.c Antonino A. Daplas 2007-05-08 1135 info->pixmap.blit_y);
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1136 vc->vc_font.width = font->width;
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1137 vc->vc_font.height = font->height;
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1138 vc->vc_font.data = (void *)(p->fontdata = font->data);
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1139 vc->vc_font.charcount = 256; /* FIXME Need to
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1140 support more fonts */
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1141 }
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1142 }
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1143
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1144 if (p->userfont)
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1145 charcnt = FNTCHARCNT(p->fontdata);
e614b18dcedb24 drivers/video/console/fbcon.c Antonino A. Daplas 2006-06-26 1146
b8c909454f046b drivers/video/console/fbcon.c Antonino A. Daplas 2005-09-09 1147 vc->vc_can_do_color = (fb_get_color_depth(&info->var, &info->fix)!=1);
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1148 vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1149 if (charcnt == 256) {
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1150 vc->vc_hi_font_mask = 0;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1151 } else {
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1152 vc->vc_hi_font_mask = 0x100;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1153 if (vc->vc_can_do_color)
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1154 vc->vc_complement_mask <<= 1;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1155 }
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1156
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1157 if (!*svc->vc_uni_pagedir_loc)
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1158 con_set_default_unimap(svc);
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1159 if (!*vc->vc_uni_pagedir_loc)
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1160 con_copy_unimap(vc, svc);
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1161
e4fc27618b7523 drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-08 1162 ops = info->fbcon_par;
f235f664a8afab drivers/video/console/fbcon.c Scot Doyle 2015-10-09 1163 ops->cur_blink_jiffies = msecs_to_jiffies(vc->vc_cur_blink_ms);
c9e6a36492504e drivers/video/fbdev/core/fbcon.c Hans de Goede 2017-11-25 1164
2428e59b530928 drivers/video/console/fbcon.c Marcin Slusarz 2008-02-06 1165 p->con_rotate = initial_rotation;
c9e6a36492504e drivers/video/fbdev/core/fbcon.c Hans de Goede 2017-11-25 1166 if (p->con_rotate == -1)
c9e6a36492504e drivers/video/fbdev/core/fbcon.c Hans de Goede 2017-11-25 1167 p->con_rotate = info->fbcon_rotate_hint;
c9e6a36492504e drivers/video/fbdev/core/fbcon.c Hans de Goede 2017-11-25 1168 if (p->con_rotate == -1)
f2f4946b0adfd6 drivers/video/fbdev/core/fbcon.c Hans de Goede 2017-11-25 1169 p->con_rotate = FB_ROTATE_UR;
c9e6a36492504e drivers/video/fbdev/core/fbcon.c Hans de Goede 2017-11-25 1170
b73deed32d0874 drivers/video/console/fbcon.c Antonino A. Daplas 2006-01-09 1171 set_blitting_type(vc, info);
e4fc27618b7523 drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-08 1172
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1173 cols = vc->vc_cols;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1174 rows = vc->vc_rows;
e4fc27618b7523 drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-08 1175 new_cols = FBCON_SWAP(ops->rotate, info->var.xres, info->var.yres);
e4fc27618b7523 drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-08 1176 new_rows = FBCON_SWAP(ops->rotate, info->var.yres, info->var.xres);
e4fc27618b7523 drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-08 1177 new_cols /= vc->vc_font.width;
e4fc27618b7523 drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-08 1178 new_rows /= vc->vc_font.height;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1179
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1180 /*
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1181 * We must always set the mode. The mode of the previous console
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1182 * driver could be in the same resolution but we are using different
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1183 * hardware so we have to initialize the hardware.
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1184 *
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1185 * We need to do it in fbcon_init() to prevent screen corruption.
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1186 */
6ca8dfd78187d8 drivers/video/console/fbcon.c Jiri Slaby 2016-06-23 1187 if (con_is_visible(vc) && vc->vc_mode == KD_TEXT) {
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1188 if (info->fbops->fb_set_par &&
0fcf6ada2b8eb4 drivers/video/console/fbcon.c Florian Tobias Schandinat 2009-09-22 1189 !(ops->flags & FBCON_FLAGS_INIT)) {
0fcf6ada2b8eb4 drivers/video/console/fbcon.c Florian Tobias Schandinat 2009-09-22 1190 ret = info->fbops->fb_set_par(info);
0fcf6ada2b8eb4 drivers/video/console/fbcon.c Florian Tobias Schandinat 2009-09-22 1191
0fcf6ada2b8eb4 drivers/video/console/fbcon.c Florian Tobias Schandinat 2009-09-22 1192 if (ret)
0fcf6ada2b8eb4 drivers/video/console/fbcon.c Florian Tobias Schandinat 2009-09-22 1193 printk(KERN_ERR "fbcon_init: detected "
0fcf6ada2b8eb4 drivers/video/console/fbcon.c Florian Tobias Schandinat 2009-09-22 1194 "unhandled fb_set_par error, "
0fcf6ada2b8eb4 drivers/video/console/fbcon.c Florian Tobias Schandinat 2009-09-22 1195 "error code %d\n", ret);
0fcf6ada2b8eb4 drivers/video/console/fbcon.c Florian Tobias Schandinat 2009-09-22 1196 }
0fcf6ada2b8eb4 drivers/video/console/fbcon.c Florian Tobias Schandinat 2009-09-22 1197
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1198 ops->flags |= FBCON_FLAGS_INIT;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1199 }
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1200
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1201 ops->graphics = 0;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1202
b457f0ea024ca7 drivers/video/fbdev/core/fbcon.c Daniel Vetter 2020-10-29 1203 /*
b457f0ea024ca7 drivers/video/fbdev/core/fbcon.c Daniel Vetter 2020-10-29 1204 * No more hw acceleration for fbcon.
b457f0ea024ca7 drivers/video/fbdev/core/fbcon.c Daniel Vetter 2020-10-29 1205 *
b457f0ea024ca7 drivers/video/fbdev/core/fbcon.c Daniel Vetter 2020-10-29 1206 * FIXME: Garbage collect all the now dead code after sufficient time
b457f0ea024ca7 drivers/video/fbdev/core/fbcon.c Daniel Vetter 2020-10-29 1207 * has passed.
b457f0ea024ca7 drivers/video/fbdev/core/fbcon.c Daniel Vetter 2020-10-29 1208 */
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1209 p->scrollmode = SCROLL_REDRAW;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1210
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1211 /*
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1212 * ++guenther: console.c:vc_allocate() relies on initializing
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1213 * vc_{cols,rows}, but we must not set those if we are only
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1214 * resizing the console.
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1215 */
0035fe00f77d2b drivers/video/console/fbcon.c Johannes Weiner 2009-08-06 1216 if (init) {
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1217 vc->vc_cols = new_cols;
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1218 vc->vc_rows = new_rows;
0035fe00f77d2b drivers/video/console/fbcon.c Johannes Weiner 2009-08-06 1219 } else
0035fe00f77d2b drivers/video/console/fbcon.c Johannes Weiner 2009-08-06 1220 vc_resize(vc, new_cols, new_rows);
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1221
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1222 if (logo)
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1223 fbcon_prepare_logo(vc, info, cols, rows, new_cols, new_rows);
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1224
4d9c5b6eb42d9e drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-07 1225 if (vc == svc && softback_buf)
4d9c5b6eb42d9e drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-07 1226 fbcon_update_softback(vc);
e4fc27618b7523 drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-08 1227
b73deed32d0874 drivers/video/console/fbcon.c Antonino A. Daplas 2006-01-09 1228 if (ops->rotate_font && ops->rotate_font(info, vc)) {
e4fc27618b7523 drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-08 1229 ops->rotate = FB_ROTATE_UR;
b73deed32d0874 drivers/video/console/fbcon.c Antonino A. Daplas 2006-01-09 1230 set_blitting_type(vc, info);
e4fc27618b7523 drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-08 1231 }
e4fc27618b7523 drivers/video/console/fbcon.c Antonino A. Daplas 2005-11-08 1232
1a37d5f51020b9 drivers/video/console/fbcon.c Antonino A. Daplas 2006-03-31 1233 ops->p = &fb_display[fg_console];
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1234 }
^1da177e4c3f41 drivers/video/console/fbcon.c Linus Torvalds 2005-04-16 1235
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Am 29.10.20 um 11:14 schrieb Daniel Vetter: > So ever since syzbot discovered fbcon, we have solid proof that it's > full of bugs. And often the solution is to just delete code and remove > features, e.g. 50145474f6ef ("fbcon: remove soft scrollback code"). > > Now the problem is that most modern-ish drivers really only treat > fbcon as an dumb kernel console until userspace takes over, and Oops > printer for some emergencies. Looking at drm drivers and the basic > vesa/efi fbdev drivers shows that only 3 drivers support any kind of > acceleration: > > - nouveau, seems to be enabled by default > - omapdrm, when a DMM remapper exists using remapper rewriting for > y/xpanning > - gma500, but that is getting deleted now for the GTT remapper trick, > and the accelerated copyarea never set the FBINFO_HWACCEL_COPYAREA > flag, so unused (and could be deleted already I think). > > No other driver supportes accelerated fbcon. And fbcon is the only > user of this accel code (it's not exposed as uapi through ioctls), > which means we could garbage collect fairly enormous amounts of code > if we kill this. > > Plus because syzbot only runs on virtual hardware, and none of the > drivers for that have acceleration, we'd remove a huge gap in testing. > And there's no other even remotely comprehensive testing aside from > syzbot. > > This patch here just disables the acceleration code by always > redrawing when scrolling. The plan is that once this has been merged > for well over a year in released kernels, we can start to go around > and delete a lot of code. > > v2: > - Drop a few more unused local variables, somehow I missed the > compiler warnings (Sam) > - Fix typo in comment (Jiri) > - add a todo entry for the cleanup (Thomas) Thanks :) > > Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de> > Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Acked-by: Sam Ravnborg <sam@ravnborg.org> > Cc: Jiri Slaby <jirislaby@kernel.org> > Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Cc: Linus Torvalds <torvalds@linux-foundation.org> > Cc: Ben Skeggs <bskeggs@redhat.com> > Cc: nouveau@lists.freedesktop.org > Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch> > Cc: Jiri Slaby <jirislaby@kernel.org> > Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org> > Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> > Cc: Peilin Ye <yepeilin.cs@gmail.com> > Cc: George Kennedy <george.kennedy@oracle.com> > Cc: Nathan Chancellor <natechancellor@gmail.com> > Cc: Peter Rosin <peda@axentia.se> > Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> > --- > Documentation/gpu/todo.rst | 18 ++++++++++++++ > drivers/video/fbdev/core/fbcon.c | 42 ++++++-------------------------- > 2 files changed, 25 insertions(+), 35 deletions(-) > > diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst > index 6b224ef14455..bec99341a904 100644 > --- a/Documentation/gpu/todo.rst > +++ b/Documentation/gpu/todo.rst > @@ -277,6 +277,24 @@ Contact: Daniel Vetter, Noralf Tronnes > > Level: Advanced > > +Garbage collect fbdev scrolling acceleration > +-------------------------------------------- > + > +Scroll acceleration is disabled in fbcon by hard-wiring p->scrollmode = > +SCROLL_REDRAW. There's a ton of code this will allow us to remove: > +- lots of code in fbcon.c > +- a bunch of the hooks in fbcon_ops, maybe the remaining hooks could be called > + directly instead of the function table (with a switch on p->rotate) > +- fb_copyarea is unused after this, and can be deleted from all drivers > + > +Note that not all acceleration code can be deleted, since clearing and cursor > +support is still accelerated, which might be good candidates for further > +deletion projects. > + > +Contact: Daniel Vetter > + > +Level: Intermediate > + > idr_init_base() > --------------- > > diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c > index cef437817b0d..a68253485244 100644 > --- a/drivers/video/fbdev/core/fbcon.c > +++ b/drivers/video/fbdev/core/fbcon.c > @@ -1147,11 +1147,13 @@ static void fbcon_init(struct vc_data *vc, int init) > > ops->graphics = 0; > > - if ((cap & FBINFO_HWACCEL_COPYAREA) && > - !(cap & FBINFO_HWACCEL_DISABLED)) > - p->scrollmode = SCROLL_MOVE; > - else /* default to something safe */ > - p->scrollmode = SCROLL_REDRAW; > + /* > + * No more hw acceleration for fbcon. > + * > + * FIXME: Garbage collect all the now dead code after sufficient time > + * has passed. > + */ > + p->scrollmode = SCROLL_REDRAW; > > /* > * ++guenther: console.c:vc_allocate() relies on initializing > @@ -1961,45 +1963,15 @@ static void updatescrollmode(struct fbcon_display *p, > { > struct fbcon_ops *ops = info->fbcon_par; > int fh = vc->vc_font.height; > - int cap = info->flags; > - u16 t = 0; > - int ypan = FBCON_SWAP(ops->rotate, info->fix.ypanstep, > - info->fix.xpanstep); > - int ywrap = FBCON_SWAP(ops->rotate, info->fix.ywrapstep, t); > int yres = FBCON_SWAP(ops->rotate, info->var.yres, info->var.xres); > int vyres = FBCON_SWAP(ops->rotate, info->var.yres_virtual, > info->var.xres_virtual); > - int good_pan = (cap & FBINFO_HWACCEL_YPAN) && > - divides(ypan, vc->vc_font.height) && vyres > yres; > - int good_wrap = (cap & FBINFO_HWACCEL_YWRAP) && > - divides(ywrap, vc->vc_font.height) && > - divides(vc->vc_font.height, vyres) && > - divides(vc->vc_font.height, yres); > - int reading_fast = cap & FBINFO_READS_FAST; > - int fast_copyarea = (cap & FBINFO_HWACCEL_COPYAREA) && > - !(cap & FBINFO_HWACCEL_DISABLED); > - int fast_imageblit = (cap & FBINFO_HWACCEL_IMAGEBLIT) && > - !(cap & FBINFO_HWACCEL_DISABLED); > > p->vrows = vyres/fh; > if (yres > (fh * (vc->vc_rows + 1))) > p->vrows -= (yres - (fh * vc->vc_rows)) / fh; > if ((yres % fh) && (vyres % fh < yres % fh)) > p->vrows--; > - > - if (good_wrap || good_pan) { > - if (reading_fast || fast_copyarea) > - p->scrollmode = good_wrap ? > - SCROLL_WRAP_MOVE : SCROLL_PAN_MOVE; > - else > - p->scrollmode = good_wrap ? SCROLL_REDRAW : > - SCROLL_PAN_REDRAW; > - } else { > - if (reading_fast || (fast_copyarea && !fast_imageblit)) > - p->scrollmode = SCROLL_MOVE; > - else > - p->scrollmode = SCROLL_REDRAW; > - } > } > > #define PITCH(w) (((w) + 7) >> 3) >
diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst index 6b224ef14455..bec99341a904 100644 --- a/Documentation/gpu/todo.rst +++ b/Documentation/gpu/todo.rst @@ -277,6 +277,24 @@ Contact: Daniel Vetter, Noralf Tronnes Level: Advanced +Garbage collect fbdev scrolling acceleration +-------------------------------------------- + +Scroll acceleration is disabled in fbcon by hard-wiring p->scrollmode = +SCROLL_REDRAW. There's a ton of code this will allow us to remove: +- lots of code in fbcon.c +- a bunch of the hooks in fbcon_ops, maybe the remaining hooks could be called + directly instead of the function table (with a switch on p->rotate) +- fb_copyarea is unused after this, and can be deleted from all drivers + +Note that not all acceleration code can be deleted, since clearing and cursor +support is still accelerated, which might be good candidates for further +deletion projects. + +Contact: Daniel Vetter + +Level: Intermediate + idr_init_base() --------------- diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c index cef437817b0d..a68253485244 100644 --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -1147,11 +1147,13 @@ static void fbcon_init(struct vc_data *vc, int init) ops->graphics = 0; - if ((cap & FBINFO_HWACCEL_COPYAREA) && - !(cap & FBINFO_HWACCEL_DISABLED)) - p->scrollmode = SCROLL_MOVE; - else /* default to something safe */ - p->scrollmode = SCROLL_REDRAW; + /* + * No more hw acceleration for fbcon. + * + * FIXME: Garbage collect all the now dead code after sufficient time + * has passed. + */ + p->scrollmode = SCROLL_REDRAW; /* * ++guenther: console.c:vc_allocate() relies on initializing @@ -1961,45 +1963,15 @@ static void updatescrollmode(struct fbcon_display *p, { struct fbcon_ops *ops = info->fbcon_par; int fh = vc->vc_font.height; - int cap = info->flags; - u16 t = 0; - int ypan = FBCON_SWAP(ops->rotate, info->fix.ypanstep, - info->fix.xpanstep); - int ywrap = FBCON_SWAP(ops->rotate, info->fix.ywrapstep, t); int yres = FBCON_SWAP(ops->rotate, info->var.yres, info->var.xres); int vyres = FBCON_SWAP(ops->rotate, info->var.yres_virtual, info->var.xres_virtual); - int good_pan = (cap & FBINFO_HWACCEL_YPAN) && - divides(ypan, vc->vc_font.height) && vyres > yres; - int good_wrap = (cap & FBINFO_HWACCEL_YWRAP) && - divides(ywrap, vc->vc_font.height) && - divides(vc->vc_font.height, vyres) && - divides(vc->vc_font.height, yres); - int reading_fast = cap & FBINFO_READS_FAST; - int fast_copyarea = (cap & FBINFO_HWACCEL_COPYAREA) && - !(cap & FBINFO_HWACCEL_DISABLED); - int fast_imageblit = (cap & FBINFO_HWACCEL_IMAGEBLIT) && - !(cap & FBINFO_HWACCEL_DISABLED); p->vrows = vyres/fh; if (yres > (fh * (vc->vc_rows + 1))) p->vrows -= (yres - (fh * vc->vc_rows)) / fh; if ((yres % fh) && (vyres % fh < yres % fh)) p->vrows--; - - if (good_wrap || good_pan) { - if (reading_fast || fast_copyarea) - p->scrollmode = good_wrap ? - SCROLL_WRAP_MOVE : SCROLL_PAN_MOVE; - else - p->scrollmode = good_wrap ? SCROLL_REDRAW : - SCROLL_PAN_REDRAW; - } else { - if (reading_fast || (fast_copyarea && !fast_imageblit)) - p->scrollmode = SCROLL_MOVE; - else - p->scrollmode = SCROLL_REDRAW; - } } #define PITCH(w) (((w) + 7) >> 3)
So ever since syzbot discovered fbcon, we have solid proof that it's full of bugs. And often the solution is to just delete code and remove features, e.g. 50145474f6ef ("fbcon: remove soft scrollback code"). Now the problem is that most modern-ish drivers really only treat fbcon as an dumb kernel console until userspace takes over, and Oops printer for some emergencies. Looking at drm drivers and the basic vesa/efi fbdev drivers shows that only 3 drivers support any kind of acceleration: - nouveau, seems to be enabled by default - omapdrm, when a DMM remapper exists using remapper rewriting for y/xpanning - gma500, but that is getting deleted now for the GTT remapper trick, and the accelerated copyarea never set the FBINFO_HWACCEL_COPYAREA flag, so unused (and could be deleted already I think). No other driver supportes accelerated fbcon. And fbcon is the only user of this accel code (it's not exposed as uapi through ioctls), which means we could garbage collect fairly enormous amounts of code if we kill this. Plus because syzbot only runs on virtual hardware, and none of the drivers for that have acceleration, we'd remove a huge gap in testing. And there's no other even remotely comprehensive testing aside from syzbot. This patch here just disables the acceleration code by always redrawing when scrolling. The plan is that once this has been merged for well over a year in released kernels, we can start to go around and delete a lot of code. v2: - Drop a few more unused local variables, somehow I missed the compiler warnings (Sam) - Fix typo in comment (Jiri) - add a todo entry for the cleanup (Thomas) Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Sam Ravnborg <sam@ravnborg.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: nouveau@lists.freedesktop.org Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Peilin Ye <yepeilin.cs@gmail.com> Cc: George Kennedy <george.kennedy@oracle.com> Cc: Nathan Chancellor <natechancellor@gmail.com> Cc: Peter Rosin <peda@axentia.se> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> --- Documentation/gpu/todo.rst | 18 ++++++++++++++ drivers/video/fbdev/core/fbcon.c | 42 ++++++-------------------------- 2 files changed, 25 insertions(+), 35 deletions(-)