kernel/drivers/video/fbdev/core/fbcon.c, branch linux-5.1.y

fbcon: Don't reset logo_shown when logo is currently shown

2019-06-15T09:52:57Z

[ Upstream commit 3c5a1b111373e669c8220803464c3a508a87e254 ] When the logo is currently drawn on a virtual console, and the console loglevel is reduced to quiet, logo_shown must be left alone, so that it the scrolling region on that virtual console is properly reset. Fixes: 10993504d647 ("fbcon: Silence fbcon logo on 'quiet' boots") Signed-off-by: Andreas Schwab Cc: Prarit Bhargava Cc: Yisheng Xie Cc: Kees Cook Cc: Daniel Vetter Cc: Steven Rostedt Cc: Marko Myllynen Cc: Hans de Goede Cc: Thierry Reding Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Sasha Levin

vt/fbcon: deinitialize resources in visual_init() after failed memory allocation

2019-06-09T07:16:15Z

commit a1ad1cc9704f64c169261a76e1aee1cf1ae51832 upstream. After memory allocation failure vc_allocate() doesn't clean up data which has been initialized in visual_init(). In case of fbcon this leads to divide-by-0 in fbcon_init() on next open of the same tty. memory allocation in vc_allocate() may fail here: 1097: vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL); on next open() fbcon_init() skips vc_font.data initialization: 1088: if (!p->fontdata) { division by zero in fbcon_init() happens here: 1149: new_cols /= vc->vc_font.width; Additional check is needed in fbcon_deinit() to prevent usage of uninitialized vc_screenbuf: 1251: if (vc->vc_hi_font_mask && vc->vc_screenbuf) 1252: set_vc_hi_font(vc, false); Crash: #6 [ffffc90001eafa60] divide_error at ffffffff81a00be4 [exception RIP: fbcon_init+463] RIP: ffffffff814b860f RSP: ffffc90001eafb18 RFLAGS: 00010246 ... #7 [ffffc90001eafb60] visual_init at ffffffff8154c36e #8 [ffffc90001eafb80] vc_allocate at ffffffff8154f53c #9 [ffffc90001eafbc8] con_install at ffffffff8154f624 ... Signed-off-by: Grzegorz Halat Reviewed-by: Oleksandr Natalenko Acked-by: Bartlomiej Zolnierkiewicz Cc: stable Signed-off-by: Greg Kroah-Hartman

fbcon: Silence fbcon logo on 'quiet' boots

2019-02-08T18:24:49Z

On text-based systems the 'quiet' boot option will show printk levels higher than CONSOLE_LOGLEVEL_QUIET. The displaying of the Tux logo during boot can cause some consoles to lose display data and as a result confuse the end user. Do not display the Tux logo on systems that are in 'quiet' boot. v2: It helps to commit all my changes before sending them. Remove extra bracket. v3: buildbot error fix: fbcon can be built as part of a module so export console_printk v4: move console_printk change to separate patch, and drop logo cleanup v5: Only set FBCON_LOGO_DONTSHOW for console loglevel Signed-off-by: Prarit Bhargava Cc: Hans de Goede Cc: Marko Myllynen Cc: Steven Rostedt (VMware) Cc: Kees Cook Cc: Daniel Vetter Cc: Thierry Reding Cc: Yisheng Xie Signed-off-by: Bartlomiej Zolnierkiewicz

fbcon: use kvmalloc() for scrollback buffer

2019-02-08T18:24:45Z

Scrollback frame buffer is rather big - 32K, so it requires 3rd order page, so let's use kvmalloc() instead of ordinary kmalloc() for it. Signed-off-by: Konstantin Khorenko Signed-off-by: Bartlomiej Zolnierkiewicz

fbdev: fbmem: convert CONFIG_FB_LOGO_CENTER into a cmd line option

2019-01-16T16:42:35Z

A command line option is much more flexible than a config option and the supporting code is small. Gets rid of #ifdefs in the code too... Suggested-by: Geert Uytterhoeven Cc: Jonathan Corbet Signed-off-by: Peter Rosin Signed-off-by: Bartlomiej Zolnierkiewicz

fbdev: fbcon: Fix unregister crash when more than one framebuffer

2018-12-20T18:13:09Z

When unregistering fbdev using unregister_framebuffer(), any bound console will unbind automatically. This is working fine if this is the only framebuffer, resulting in a switch to the dummy console. However if there is a fb0 and I unregister fb1 having a bound console, I eventually get a crash. The fastest way for me to trigger the crash is to do a reboot, resulting in this splat: [ 76.478825] WARNING: CPU: 0 PID: 527 at linux/kernel/workqueue.c:1442 __queue_work+0x2d4/0x41c [ 76.478849] Modules linked in: raspberrypi_hwmon gpio_backlight backlight bcm2835_rng rng_core [last unloaded: tinydrm] [ 76.478916] CPU: 0 PID: 527 Comm: systemd-udevd Not tainted 4.20.0-rc4+ #4 [ 76.478933] Hardware name: BCM2835 [ 76.478949] Backtrace: [ 76.478995] [] (dump_backtrace) from [] (show_stack+0x20/0x24) [ 76.479022] r6:00000000 r5:c0bc73be r4:00000000 r3:6fb5bf81 [ 76.479060] [] (show_stack) from [] (dump_stack+0x20/0x28) [ 76.479102] [] (dump_stack) from [] (__warn+0xec/0x12c) [ 76.479134] [] (__warn) from [] (warn_slowpath_null+0x4c/0x58) [ 76.479165] r9:c0eb6944 r8:00000001 r7:c0e927f8 r6:c0bc73be r5:000005a2 r4:c0139e84 [ 76.479197] [] (warn_slowpath_null) from [] (__queue_work+0x2d4/0x41c) [ 76.479222] r6:d7666a00 r5:c0e918ee r4:dbc4e700 [ 76.479251] [] (__queue_work) from [] (queue_work_on+0x60/0x88) [ 76.479281] r10:c0496bf8 r9:00000100 r8:c0e92ae0 r7:00000001 r6:d9403700 r5:d7666a00 [ 76.479298] r4:20000113 [ 76.479348] [] (queue_work_on) from [] (cursor_timer_handler+0x30/0x54) [ 76.479374] r7:d8a8fabc r6:c0e08088 r5:d8afdc5c r4:d8a8fabc [ 76.479413] [] (cursor_timer_handler) from [] (call_timer_fn+0x100/0x230) [ 76.479435] r4:c0e9192f r3:d758a340 [ 76.479465] [] (call_timer_fn) from [] (expire_timers+0x10c/0x12c) [ 76.479495] r10:40000000 r9:c0e9192f r8:c0e92ae0 r7:d8afdccc r6:c0e19280 r5:c0496bf8 [ 76.479513] r4:d8a8fabc [ 76.479541] [] (expire_timers) from [] (run_timer_softirq+0xa8/0x184) [ 76.479570] r9:00000001 r8:c0e19280 r7:00000000 r6:c0e08088 r5:c0e1a3e0 r4:c0e19280 [ 76.479603] [] (run_timer_softirq) from [] (__do_softirq+0x1ac/0x3fc) [ 76.479632] r10:c0e91680 r9:d8afc020 r8:0000000a r7:00000100 r6:00000001 r5:00000002 [ 76.479650] r4:c0eb65ec [ 76.479686] [] (__do_softirq) from [] (irq_exit+0xe8/0x168) [ 76.479716] r10:d8d1a9b0 r9:d8afc000 r8:00000001 r7:d949c000 r6:00000000 r5:c0e8b3f0 [ 76.479734] r4:00000000 [ 76.479764] [] (irq_exit) from [] (__handle_domain_irq+0x94/0xb0) [ 76.479793] [] (__handle_domain_irq) from [] (bcm2835_handle_irq+0x3c/0x48) [ 76.479823] r8:d8afdebc r7:d8afddfc r6:ffffffff r5:c0e089f8 r4:d8afddc8 r3:d8afddc8 [ 76.479851] [] (bcm2835_handle_irq) from [] (__irq_svc+0x70/0x98) The problem is in the console rebinding in fbcon_fb_unbind(). It uses the virtual console index as the new framebuffer index to bind the console(s) to. The correct way is to use the con2fb_map lookup table to find the framebuffer index. Fixes: cfafca8067c6 ("fbdev: fbcon: console unregistration from unregister_framebuffer") Signed-off-by: Noralf Trønnes Reviewed-by: Mikulas Patocka Acked-by: Daniel Vetter Signed-off-by: Bartlomiej Zolnierkiewicz

vt: Remove vc_panic_force_write

2018-09-11T12:11:51Z

It was only used by the panic support in fbcon, which is now gone. Remove this now dead code too. Acked-by: Greg Kroah-Hartman Cc: Greg Kroah-Hartman Cc: Kees Cook Cc: Joe Perches Cc: Daniel Vetter Cc: Meng Xu Cc: Nicolas Pitre Cc: Thomas Meyer Cc: Mike Frysinger Cc: Bartlomiej Zolnierkiewicz Cc: Hans de Goede Cc: Thierry Reding Cc: David Lechner Cc: Philippe Ombredanne Cc: Thomas Gleixner Cc: Kate Stewart Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20180822085405.10787-2-daniel.vetter@ffwll.ch

fbdev: Drop FBINFO_CAN_FORCE_OUTPUT flag

2018-09-11T12:11:01Z

This was only added for the drm's fbdev emulation support, so that it would try harder to show the Oops. Unfortunately this never really worked reliably, and in practice ended up pushing the real Oops off the screen due to plentyfull locking, sleep-while-atomic and other issues. So we removed all that support from the fbdev emulation a while back. Aside: We've also removed the kgdb support, for similar reasons. Since it's such a small patch I figured I don't split this up into the usual 3-phase removal. Acked-by: Bartlomiej Zolnierkiewicz Cc: Ben Skeggs Cc: Bartlomiej Zolnierkiewicz Cc: Greg Kroah-Hartman Cc: Hans de Goede Cc: Daniel Vetter Cc: Alexander Kapshuk Cc: Kees Cook Cc: Thierry Reding Cc: David Lechner Cc: nouveau@lists.freedesktop.org Cc: linux-fbdev@vger.kernel.org Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20180822085405.10787-1-daniel.vetter@ffwll.ch

fbcon: Do not takeover the console from atomic context

2018-08-10T15:23:02Z

Taking over the console involves allocating mem with GFP_KERNEL, talking to drm drivers, etc. So this should not be done from an atomic context. But the console-output trigger deferred console takeover may happen from an atomic context, which leads to "BUG: sleeping function called from invalid context" errors. This commit fixes these errors by doing the deferred takeover from a workqueue. Signed-off-by: Hans de Goede [b.zolnierkie: remove unused variable] Signed-off-by: Bartlomiej Zolnierkiewicz

fbcon: Only defer console takeover if the current console driver is the dummycon

2018-08-10T15:23:01Z

We rely on dummycon's output notifier mechanism to defer the takeover. If say vgacon is the current console driver then dummycon will never get used so its output notifier will also never get called and fbcon never takes over. This commit fixes this by only deferring the console takeover if the current console driver is the dummycon driver. This commit also moves the entirety of fbcon_start under the console_lock, since the conswitchp which fbcon_start now checks is protected by it. This commit also inlines fbcon_register_output_notifier, since we now need a #ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER in fbcon_start anyways because of the write access to the deferred_takeover variable, this has the added advantage that it puts the dummycon_register_output_notifier() call directly after the "conswitchp != &dummy_con" comparison making it clear why that check is there. Note the arch setup code will set conswitchp to either dummy_con or vga_con, in the cases where it gets set to vga_con even though their is no vga_con present we rely on vga_con_startup() to set conswitchp to dummy_con. vga_con_startup() is guaranteed to happen before fb_console_init() as it gets called as a console_initcall where as fb_console_init() gets called as a subsys_initcall. Signed-off-by: Hans de Goede Signed-off-by: Bartlomiej Zolnierkiewicz