On 27 May 2015 at 13:19, Andrey Wagin <[email protected]> wrote: > 2015-05-21 10:58 GMT+03:00 Thierry Reding <[email protected]>: >> From: Thierry Reding <[email protected]> >> >> Commit 27a4c827c34a ("fbcon: use the cursor blink interval provided by >> vt") unconditionally removes the cursor blink timer. Unfortunately that >> wreaks havoc under some circumstances. An easily reproducible way is to >> use both the framebuffer console and a debug serial port as the console >> output for kernel messages (e.g. "console=ttyS0 console=tty1" on the >> kernel command-line. Upon boot this triggers a warning from within the >> del_timer_sync() function because it is called from IRQ context: >> >> [ 5.070096] ------------[ cut here ]------------ >> [ 5.070110] WARNING: CPU: 0 PID: 0 at ../kernel/time/timer.c:1098 >> del_timer_sync+0x4c/0x54() >> [ 5.070115] Modules linked in: >> [ 5.070120] CPU: 0 PID: 0 Comm: swapper/0 Not tainted >> 4.1.0-rc4-next-20150519 #1 >> [ 5.070123] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) >> [ 5.070142] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) >> [ 5.070156] [] (show_stack) from [] (dump_stack+0x70/0xbc) >> [ 5.070164] [] (dump_stack) from [] >> (warn_slowpath_common+0x74/0xb0) >> [ 5.070169] [] (warn_slowpath_common) from [] >> (warn_slowpath_null+0x1c/0x24) >> [ 5.070174] [] (warn_slowpath_null) from [] >> (del_timer_sync+0x4c/0x54) >> [ 5.070183] [] (del_timer_sync) from [] >> (fbcon_del_cursor_timer+0x2c/0x40) >> [ 5.070190] [] (fbcon_del_cursor_timer) from [] >> (fbcon_cursor+0x9c/0x180) >> [ 5.070198] [] (fbcon_cursor) from [] (hide_cursor+0x30/0x98) >> [ 5.070204] [] (hide_cursor) from [] >> (vt_console_print+0x2a8/0x340) >> [ 5.070212] [] (vt_console_print) from [] >> (call_console_drivers.constprop.23+0xc8/0xec) >> [ 5.070218] [] (call_console_drivers.constprop.23) from [] >> (console_unlock+0x498/0x4f0) >> [ 5.070223] [] (console_unlock) from [] (vprintk_emit+0x1f0/0x508) >> [ 5.070228] [] (vprintk_emit) from [] (vprintk_default+0x24/0x2c) >> [ 5.070234] [] (vprintk_default) from [] (printk+0x70/0x88) >> >> After which the system starts spewing all kinds of weird and seemingly >> unrelated error messages. >> >> This commit fixes this by restoring the condition under which the call >> to fbcon_del_cursor_timer() happens. > > Tested-by: Andrew Vagin <[email protected]> > > It would be good to push this patch into linux-next asap. Without this > patch I can't execute tests on linux-next. Thanks.
Tested-by: Tomeu Vizoso <[email protected]> Same here, please apply. Thanks, Tomeu >> >> Reported-by: Daniel Stone <[email protected]> >> Reported-by: Kevin Hilman <[email protected]> >> Tested-by: Kevin Hilman <[email protected]> >> Tested-by: Scot Doyle <[email protected]> >> Signed-off-by: Thierry Reding <[email protected]> >> --- >> drivers/video/console/fbcon.c | 5 +++-- >> 1 file changed, 3 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c >> index 05b1d1a71ef9..658c34bb9076 100644 >> --- a/drivers/video/console/fbcon.c >> +++ b/drivers/video/console/fbcon.c >> @@ -1310,8 +1310,9 @@ static void fbcon_cursor(struct vc_data *vc, int mode) >> return; >> >> ops->cur_blink_jiffies = msecs_to_jiffies(vc->vc_cur_blink_ms); >> - fbcon_del_cursor_timer(info); >> - if (!(vc->vc_cursor_type & 0x10)) >> + if (vc->vc_cursor_type & 0x10) >> + fbcon_del_cursor_timer(info); >> + else >> fbcon_add_cursor_timer(info); >> >> ops->cursor_flash = (mode == CM_ERASE) ? 0 : 1; >> -- >> 2.4.1 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> the body of a message to [email protected] >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> Please read the FAQ at http://www.tux.org/lkml/ > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to [email protected] > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
