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path: root/drivers/video/console/vgacon.c
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2021-12-14Merge v5.16-rc5 into drm-nextDaniel Vetter
Thomas Zimmermann requested a fixes backmerge, specifically also for 96c5f82ef0a1 ("drm/vc4: fix error code in vc4_create_object()") Just a bunch of adjacent changes conflicts, even the big pile of them in vc4. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2021-11-27drm: Move nomodeset kernel parameter to the DRM subsystemJavier Martinez Canillas
The "nomodeset" kernel cmdline parameter is handled by the vgacon driver but the exported vgacon_text_force() symbol is only used by DRM drivers. It makes much more sense for the parameter logic to be in the subsystem of the drivers that are making use of it. Let's move the vgacon_text_force() function and related logic to the DRM subsystem. While doing that, rename it to drm_firmware_drivers_only() and make it return true if "nomodeset" was used and false otherwise. This is a better description of the condition that the drivers are testing for. Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://patchwork.freedesktop.org/patch/msgid/20211112133230.1595307-4-javierm@redhat.com
2021-11-25vgacon: Propagate console boot parameters before calling `vc_resize'Maciej W. Rozycki
Fix a division by zero in `vgacon_resize' with a backtrace like: vgacon_resize vc_do_resize vgacon_init do_bind_con_driver do_unbind_con_driver fbcon_fb_unbind do_unregister_framebuffer do_register_framebuffer register_framebuffer __drm_fb_helper_initial_config_and_unlock drm_helper_hpd_irq_event dw_hdmi_irq irq_thread kthread caused by `c->vc_cell_height' not having been initialized. This has only started to trigger with commit 860dafa90259 ("vt: Fix character height handling with VT_RESIZEX"), however the ultimate offender is commit 50ec42edd978 ("[PATCH] Detaching fbcon: fix vgacon to allow retaking of the console"). Said commit has added a call to `vc_resize' whenever `vgacon_init' is called with the `init' argument set to 0, which did not happen before. And the call is made before a key vgacon boot parameter retrieved in `vgacon_startup' has been propagated in `vgacon_init' for `vc_resize' to use to the console structure being worked on. Previously the parameter was `c->vc_font.height' and now it is `c->vc_cell_height'. In this particular scenario the registration of fbcon has failed and vt resorts to vgacon. Now fbcon does have initialized `c->vc_font.height' somehow, unlike `c->vc_cell_height', which is why this code did not crash before, but either way the boot parameters should have been copied to the console structure ahead of the call to `vc_resize' rather than afterwards, so that first the call has a chance to use them and second they do not change the console structure to something possibly different from what was used by `vc_resize'. Move the propagation of the vgacon boot parameters ahead of the call to `vc_resize' then. Adjust the comment accordingly. Fixes: 50ec42edd978 ("[PATCH] Detaching fbcon: fix vgacon to allow retaking of the console") Cc: stable@vger.kernel.org # v2.6.18+ Reported-by: Wim Osterholt <wim@djo.tudelft.nl> Reported-by: Pavel V. Panteleev <panteleev_p@mcst.ru> Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2110252317110.58149@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13Merge branch 'resizex' (patches from Maciej)Linus Torvalds
Merge VT_RESIZEX fixes from Maciej Rozycki: "I got to the bottom of the issue with VT_RESIZEX recently discussed and came up with this small patch series, fixing an additional issue that I originally thought might be broken VGA hardware emulation with my laptop, which however turned out to be intertwined with the original problem and also a regression introduced somewhat later. The fix for that because the first patch, and then to make backporting feasible I had to put a revert of the offending change from last September next, followed by a proper fix for the framebuffer issue that change had tried to address. See individual change descriptions for details. These have been verified with true VGA hardware (a Trident TVGA8900 ISA video adapter) using various combinations of `svgatextmode' and `setfont' command invocations to change both the VT size and the font size, and also switching between the text console and X11, both by starting/stopping the X server and by switching between VTs. All this to ensure bringing the behaviour of VGA text console back to correct operation as it used to be with Linux 2.6.18" * emailed patches from Maciej W. Rozycki <macro@orcam.me.uk>: vt: Fix character height handling with VT_RESIZEX vt_ioctl: Revert VT_RESIZEX parameter handling removal vgacon: Record video mode changes with VT_RESIZEX
2021-05-13vt: Fix character height handling with VT_RESIZEXMaciej W. Rozycki
Restore the original intent of the VT_RESIZEX ioctl's `v_clin' parameter which is the number of pixel rows per character (cell) rather than the height of the font used. For framebuffer devices the two values are always the same, because the former is inferred from the latter one. For VGA used as a true text mode device these two parameters are independent from each other: the number of pixel rows per character is set in the CRT controller, while font height is in fact hardwired to 32 pixel rows and fonts of heights below that value are handled by padding their data with blanks when loaded to hardware for use by the character generator. One can change the setting in the CRT controller and it will update the screen contents accordingly regardless of the font loaded. The `v_clin' parameter is used by the `vgacon' driver to set the height of the character cell and then the cursor position within. Make the parameter explicit then, by defining a new `vc_cell_height' struct member of `vc_data', set it instead of `vc_font.height' from `v_clin' in the VT_RESIZEX ioctl, and then use it throughout the `vgacon' driver except where actual font data is accessed which as noted above is independent from the CRTC setting. This way the framebuffer console driver is free to ignore the `v_clin' parameter as irrelevant, as it always should have, avoiding any issues attempts to give the parameter a meaning there could have caused, such as one that has led to commit 988d0763361b ("vt_ioctl: make VT_RESIZEX behave like VT_RESIZE"): "syzbot is reporting UAF/OOB read at bit_putcs()/soft_cursor() [1][2], for vt_resizex() from ioctl(VT_RESIZEX) allows setting font height larger than actual font height calculated by con_font_set() from ioctl(PIO_FONT). Since fbcon_set_font() from con_font_set() allocates minimal amount of memory based on actual font height calculated by con_font_set(), use of vt_resizex() can cause UAF/OOB read for font data." The problem first appeared around Linux 2.5.66 which predates our repo history, but the origin could be identified with the old MIPS/Linux repo also at: <git://git.kernel.org/pub/scm/linux/kernel/git/ralf/linux.git> as commit 9736a3546de7 ("Merge with Linux 2.5.66."), where VT_RESIZEX code in `vt_ioctl' was updated as follows: if (clin) - video_font_height = clin; + vc->vc_font.height = clin; making the parameter apply to framebuffer devices as well, perhaps due to the use of "font" in the name of the original `video_font_height' variable. Use "cell" in the new struct member then to avoid ambiguity. References: [1] https://syzkaller.appspot.com/bug?id=32577e96d88447ded2d3b76d71254fb855245837 [2] https://syzkaller.appspot.com/bug?id=6b8355d27b2b94fb5cedf4655e3a59162d9e48e3 Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org # v2.6.12+ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-13vgacon: Record video mode changes with VT_RESIZEXMaciej W. Rozycki
Fix an issue with VGA console font size changes made after the initial video text mode has been changed with a user tool like `svgatextmode' calling the VT_RESIZEX ioctl. As it stands in that case the original screen geometry continues being used to validate further VT resizing. Consequently when the video adapter is firstly reprogrammed from the original say 80x25 text mode using a 9x16 character cell (720x400 pixel resolution) to say 80x37 text mode and the same character cell (720x592 pixel resolution), and secondly the CRTC character cell updated to 9x8 (by loading a suitable font with the KD_FONT_OP_SET request of the KDFONTOP ioctl), the VT geometry does not get further updated from 80x37 and only upper half of the screen is used for the VT, with the lower half showing rubbish corresponding to whatever happens to be there in the video memory that maps to that part of the screen. Of course the proportions change according to text mode geometries and font sizes chosen. Address the problem then, by updating the text mode geometry defaults rather than checking against them whenever the VT is resized via a user ioctl. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Fixes: e400b6ec4ede ("vt/vgacon: Check if screen resize request comes from userspace") Cc: stable@vger.kernel.org # v2.6.24+ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-23vgacon: drop unused vga_init_doneStephen Kitt
Commit 973c096f6a85 ("vgacon: remove software scrollback support") removed all uses of vga_init_done, so let's get rid of it entirely. Signed-off-by: Stephen Kitt <steve@sk2.org> Link: https://lore.kernel.org/r/20210215170837.1599706-1-steve@sk2.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10vgacon: comment on vga_rolled_overJiri Slaby
Long time ago, I figured out what this number is good for and documented that locally. But never submitted, so do it now. Cc: dri-devel@lists.freedesktop.org Cc: linux-fbdev@vger.kernel.org Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210302062214.29627-4-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07vgacon: drop BROKEN_GRAPHICS_PROGRAMSJiri Slaby
BROKEN_GRAPHICS_PROGRAMS is defined when CONFIG_VGA_CONSOLE=y. And vgacon.c is built exclusively in that case too. So the check for BROKEN_GRAPHICS_PROGRAMS is pointless in vgacon.c as it is always true. So remove the test and BROKEN_GRAPHICS_PROGRAMS completely. This also eliminates the need for vga_font_is_default global as it is only set and never read. Cc: dri-devel@lists.freedesktop.org Cc: linux-fbdev@vger.kernel.org Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-9-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-14vgacon: remove software scrollback supportLinus Torvalds
Yunhai Zhang recently fixed a VGA software scrollback bug in commit ebfdfeeae8c0 ("vgacon: Fix for missing check in scrollback handling"), but that then made people look more closely at some of this code, and there were more problems on the vgacon side, but also the fbcon software scrollback. We don't really have anybody who maintains this code - probably because nobody actually _uses_ it any more. Sure, people still use both VGA and the framebuffer consoles, but they are no longer the main user interfaces to the kernel, and haven't been for decades, so these kinds of extra features end up bitrotting and not really being used. So rather than try to maintain a likely unused set of code, I'll just aggressively remove it, and see if anybody even notices. Maybe there are people who haven't jumped on the whole GUI badnwagon yet, and think it's just a fad. And maybe those people use the scrollback code. If that turns out to be the case, we can resurrect this again, once we've found the sucker^Wmaintainer for it who actually uses it. Reported-by: NopNop Nop <nopitydays@gmail.com> Tested-by: Willy Tarreau <w@1wt.eu> Cc: 张云海 <zhangyunhai@nsfocus.com> Acked-by: Andy Lutomirski <luto@amacapital.net> Acked-by: Willy Tarreau <w@1wt.eu> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-04vgacon: Fix for missing check in scrollback handlingYunhai Zhang
vgacon_scrollback_update() always leaves enbough room in the scrollback buffer for the next call, but if the console size changed that room might not actually be enough, and so we need to re-check. The check should be in the loop since vgacon_scrollback_cur->tail is updated in the loop and count may be more than 1 when triggered by CSI M, as Jiri's PoC: #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/types.h> #include <sys/stat.h> #include <sys/ioctl.h> #include <fcntl.h> int main(int argc, char** argv) { int fd = open("/dev/tty1", O_RDWR); unsigned short size[3] = {25, 200, 0}; ioctl(fd, 0x5609, size); // VT_RESIZE write(fd, "\e[1;1H", 6); for (int i = 0; i < 30; i++) write(fd, "\e[10M", 5); } It leads to various crashes as vgacon_scrollback_update writes out of the buffer: BUG: unable to handle page fault for address: ffffc900001752a0 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page RIP: 0010:mutex_unlock+0x13/0x30 ... Call Trace: n_tty_write+0x1a0/0x4d0 tty_write+0x1a0/0x2e0 Or to KASAN reports: BUG: KASAN: slab-out-of-bounds in vgacon_scroll+0x57a/0x8ed This fixes CVE-2020-14331. Reported-by: 张云海 <zhangyunhai@nsfocus.com> Reported-by: Yang Yingliang <yangyingliang@huawei.com> Reported-by: Kyungtae Kim <kt0755@gmail.com> Fixes: 15bdab959c9b ([PATCH] vgacon: Add support for soft scrollback) Cc: stable@vger.kernel.org Cc: linux-fbdev@vger.kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Solar Designer <solar@openwall.com> Cc: "Srivatsa S. Bhat" <srivatsa@csail.mit.edu> Cc: Anthony Liguori <aliguori@amazon.com> Cc: Yang Yingliang <yangyingliang@huawei.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Yunhai Zhang <zhangyunhai@nsfocus.com> Link: https://lore.kernel.org/r/9fb43895-ca91-9b07-ebfd-808cf854ca95@nsfocus.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24vt: use newly defined CUR_* macrosJiri Slaby
We defined macros for all the magic constants in the previous patch. So let us use the macro in the code now. No functional change intended. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: linux-usb@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Cc: linux-fbdev@vger.kernel.org Cc: linux-parisc@vger.kernel.org Acked-by: Helge Deller <deller@gmx.de> Link: https://lore.kernel.org/r/20200615074910.19267-26-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24vc: switch state to boolJiri Slaby
The code currently uses bitfields to store true-false values. Switch all of that to bools. Apart from the cleanup, it saves 20B of code as many shifts, ANDs, and ORs became simple movzb's. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200615074910.19267-3-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24vt: introduce enum vc_intensity for intensityJiri Slaby
Introduce names (en enum) for 0, 1, and 2 constants. We now have VCI_HALF_BRIGHT, VCI_NORMAL, and VCI_BOLD instead. Apart from the cleanup, 1) the enum allows for better type checking, and 2) this saves some code. No more fiddling with bits is needed in assembly now. (OTOH, the structure is larger.) Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200615074910.19267-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24vc: separate stateJiri Slaby
There are two copies of some members of struct vc_data. This is because we need to save them and restore later. Move these memebers to a separate structure called vc_state. So now instead of members like: vc_x, vc_y and vc_saved_x, vc_saved_y we have state and saved_state (of type: struct vc_state) containing state.x, state.y and saved_state.x, saved_state.y This change: * makes clear what is saved & restored * eases save & restore by using memcpy (see save_cur and restore_cur) Finally, we document the newly added struct vc_state using kernel-doc. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200615074910.19267-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06vgacon: Fix a UAF in vgacon_invert_regionZhang Xiaoxu
When syzkaller tests, there is a UAF: BUG: KASan: use after free in vgacon_invert_region+0x9d/0x110 at addr ffff880000100000 Read of size 2 by task syz-executor.1/16489 page:ffffea0000004000 count:0 mapcount:-127 mapping: (null) index:0x0 page flags: 0xfffff00000000() page dumped because: kasan: bad access detected CPU: 1 PID: 16489 Comm: syz-executor.1 Not tainted Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014 Call Trace: [<ffffffffb119f309>] dump_stack+0x1e/0x20 [<ffffffffb04af957>] kasan_report+0x577/0x950 [<ffffffffb04ae652>] __asan_load2+0x62/0x80 [<ffffffffb090f26d>] vgacon_invert_region+0x9d/0x110 [<ffffffffb0a39d95>] invert_screen+0xe5/0x470 [<ffffffffb0a21dcb>] set_selection+0x44b/0x12f0 [<ffffffffb0a3bfae>] tioclinux+0xee/0x490 [<ffffffffb0a1d114>] vt_ioctl+0xff4/0x2670 [<ffffffffb0a0089a>] tty_ioctl+0x46a/0x1a10 [<ffffffffb052db3d>] do_vfs_ioctl+0x5bd/0xc40 [<ffffffffb052e2f2>] SyS_ioctl+0x132/0x170 [<ffffffffb11c9b1b>] system_call_fastpath+0x22/0x27 Memory state around the buggy address: ffff8800000fff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8800000fff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff880000100000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff It can be reproduce in the linux mainline by the program: #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <fcntl.h> #include <sys/types.h> #include <sys/stat.h> #include <sys/ioctl.h> #include <linux/vt.h> struct tiocl_selection { unsigned short xs; /* X start */ unsigned short ys; /* Y start */ unsigned short xe; /* X end */ unsigned short ye; /* Y end */ unsigned short sel_mode; /* selection mode */ }; #define TIOCL_SETSEL 2 struct tiocl { unsigned char type; unsigned char pad; struct tiocl_selection sel; }; int main() { int fd = 0; const char *dev = "/dev/char/4:1"; struct vt_consize v = {0}; struct tiocl tioc = {0}; fd = open(dev, O_RDWR, 0); v.v_rows = 3346; ioctl(fd, VT_RESIZEX, &v); tioc.type = TIOCL_SETSEL; ioctl(fd, TIOCLINUX, &tioc); return 0; } When resize the screen, update the 'vc->vc_size_row' to the new_row_size, but when 'set_origin' in 'vgacon_set_origin', vgacon use 'vga_vram_base' for 'vc_origin' and 'vc_visible_origin', not 'vc_screenbuf'. It maybe smaller than 'vc_screenbuf'. When TIOCLINUX, use the new_row_size to calc the offset, it maybe larger than the vga_vram_size in vgacon driver, then bad access. Also, if set an larger screenbuf firstly, then set an more larger screenbuf, when copy old_origin to new_origin, a bad access may happen. So, If the screen size larger than vga_vram, resize screen should be failed. This alse fix CVE-2020-8649 and CVE-2020-8647. Linus pointed out that overflow checking seems absent. We're saved by the existing bounds checks in vc_do_resize() with rather strict limits: if (cols > VC_RESIZE_MAXCOL || lines > VC_RESIZE_MAXROW) return -EINVAL; Fixes: 0aec4867dca14 ("[PATCH] SVGATextMode fix") Reference: CVE-2020-8647 and CVE-2020-8649 Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com> [danvet: augment commit message to point out overflow safety] Cc: stable@vger.kernel.org Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20200304022429.37738-1-zhangxiaoxu5@huawei.com
2019-10-18vgacon: Use pr_warn instead of pr_warningKefeng Wang
As said in commit f2c2cbcc35d4 ("powerpc: Use pr_warn instead of pr_warning"), removing pr_warning so all logging messages use a consistent <prefix>_warn style. Let's do it. Link: http://lkml.kernel.org/r/20191018031850.48498-24-wangkefeng.wang@huawei.com To: linux-kernel@vger.kernel.org Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: linux-fbdev@vger.kernel.org Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-01-18vgacon: unconfuse vc_origin when using soft scrollbackNicolas Pitre
When CONFIG_VGACON_SOFT_SCROLLBACK is selected, the VGA display memory index and vc_visible_origin don't change when scrollback is activated. The actual screen content is saved away and the scrollbackdata is copied over it. However the vt code, and /dev/vcs devices in particular, still expect vc_origin to always point at the actual screen content not the displayed scrollback content. So adjust vc_origin to point at the saved screen content when scrollback is active and set it back to vc_visible_origin when restoring the screen. This fixes /dev/vcsa<n> that return scrollback content when they shouldn't (onli /dev/vcsa without a number should), and also fixes /dev/vcsu that should return scrollback content when scrollback is active but currently doesn't. An unnecessary call to vga_set_mem_top() is also removed. Signed-off-by: Nicolas Pitre <nico@linaro.org> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-24video/console/vgacon: Print big fat warning with nomodesetLyude Paul
It's been a pretty good while since kernel modesetting was introduced. It has almost entirely replaced previous solutions which required userspace modesetting, and I can't even recall any drivers off the top of my head for modern day hardware that don't only support one or the other. Even nvidia's ugly blob does not require the use of nomodeset, and only requires that nouveau be blacklisted. Effectively, the only thing nomodeset does in the year 2018 is disable your graphics drivers. Since VESA is a thing, this will give many users the false impression that they've actually fixed an issue they were having with their machine simply because the laptop will boot up to a degraded GUI. This of course, is never actually the case. Things get even worse when you consider that there's still an enormous amount of tutorials users find on the internet that still suggest adding nomodeset, along with various users who have been around long enough to still suggest it. There really isn't any legitimate reason I can see for this to be an option that's used by anyone else other then developers, or properly informed users. So, let's end the confusion and start printing warnings whenever it's enabled. Signed-off-by: Lyude Paul <lyude@redhat.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Acked-by: Jani Nikula <jani.nikula@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: "Jan H. Schönherr" <jschoenh@amazon.de> Cc: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2018-02-27console: Expand dummy functions for CFIKees Cook
This expands the no-op dummy functions into full prototypes to avoid indirect call mismatches when running under Control Flow Integrity checking, like with Clang's -fsanitize=cfi. Co-Developed-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-18vgacon: Set VGA struct resource typesBjorn Helgaas
Set the resource type when we reserve VGA-related I/O port resources. The resource code doesn't actually look at the type, so it inserts resources without a type in the tree correctly even without this change. But if we ever print a resource without a type, it looks like this: vga+ [??? 0x000003c0-0x000003df flags 0x0] Setting the type means it will be printed correctly as: vga+ [io 0x000003c0-0x000003df] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-09-04vgacon: Prevent faulty bootparams.screeninfo from causing harmJan H. Schönherr
If a zero for the number of colums or rows manages to slip through, gotoxy() will underflow vc->vc_pos, causing the next action on the referenced memory to end with a page fault. Make the check in vgacon_startup() more pessimistic to prevent that. Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2017-01-25console: Make persistent scrollback a boot parameterManuel Schölling
The impact of the persistent scrollback feature on the code size is rather small, so the config option is removed. The feature stays disabled by default and can be enabled by using the boot command line parameter 'vgacon.scrollback_persistent=1' or by setting VGACON_SOFT_SCROLLBACK_PERSISTENT_ENABLE_BY_DEFAULT=y. Signed-off-by: Manuel Schölling <manuel.schoelling@gmx.de> Suggested-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25console: Add persistent scrollback buffers for all VGA consolesManuel Schölling
Add a scrollback buffers for each VGA console. The benefit is that the scrollback history is not flushed when switching between consoles but is persistent. The buffers are allocated on demand when a new console is opened. This breaks tools like clear_console that rely on flushing the scrollback history by switching back and forth between consoles which is why this feature is disabled by default. Use the escape sequence \e[3J instead for flushing the buffer. Signed-off-by: Manuel Schölling <manuel.schoelling@gmx.de> Reviewed-by: Andrey Utkin <andrey_utkin@fastmail.com> Tested-by: Andrey Utkin <andrey_utkin@fastmail.com> Tested-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25console: Add callback to flush scrollback buffer to consw structManuel Schölling
This new callback is in preparation for persistent scrollback buffer support for VGA consoles. With a single scrollback buffer for all consoles, we could flush the buffer just by invocating consw->con_switch(). But when each VGA console has its own scrollback buffer, we need a new callback to tell the video console driver which buffer to flush. Signed-off-by: Manuel Schölling <manuel.schoelling@gmx.de> Reviewed-by: Andrey Utkin <andrey_utkin@fastmail.com> Tested-by: Andrey Utkin <andrey_utkin@fastmail.com> Tested-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25console: Move scrollback data into its own structManuel Schölling
This refactoring is in preparation for persistent scrollback support for VGA console. Signed-off-by: Manuel Schölling <manuel.schoelling@gmx.de> Reviewed-by: Andrey Utkin <andrey_utkin@fastmail.com> Tested-by: Andrey Utkin <andrey_utkin@fastmail.com> Tested-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27vgacon: remove prehistoric macrosJiri Slaby
These macros: * CAN_LOAD_EGA_FONTS * CAN_LOAD_PALETTE * TRIDENT_GLITCH * VGA_CAN_DO_64KB * SLOW_VGA are either always set or always unset. They come from the linux 2.1 times. And given nobody switched them to some configurable options, I assume nobody actually uses them. So remove the macros and leave in place appropriate branches of the conditional code. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: <linux-fbdev@vger.kernel.org> Cc: <linux-doc@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27vgacon: switch boolean variables to boolJiri Slaby
These variables: * vga_can_do_color * vgacon_text_mode_force * vga_font_is_default * vga_hardscroll_enabled * vga_hardscroll_user_enable * vga_init_done * vga_is_gfx * vga_palette_blanked * vga_512_chars are used exclusively as a boolean value, so make them really a bool. Remove also useless "? true : false". __read_mostly annotations removed too as they obfuscate the code and I doubt they improve anything measurable given the variables are used from .con_scroll, .con_startup and such. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: <linux-fbdev@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27tty: vgacon+sisusb, move scrolldelta to a common helperJiri Slaby
The code is mirrorred in scrolldelta implementations of both vgacon and sisusb. Let's move the code to a separate helper where we will perform a common cleanup and further changes. While we are moving the code, make it linear and save one indentation level. This is done by returning from the "!lines" then-branch immediatelly. This allows flushing the else-branch 1 level to the left, obviously. Few more new lines and comments were added too. And do not forget to export the helper function given sisusb can be built as module. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: <linux-fbdev@vger.kernel.org> Cc: <linux-usb@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27tty: vt, cleanup and document con_scrollJiri Slaby
Scrolling helpers scrup and scrdown both accept 'top' and 'bottom' as unsigned int. Number of lines 'nr' is accepted as int, but all callers pass down unsigned too. So change the type of 'nr' to unsigned too. Now, promote unsigned int from the helpers up to the con_scroll hook which actually accepted all those as signed int. Next, the 'dir' parameter can have only two values and we define constants for that: SM_UP and SM_DOWN. Switch them to enum and do proper type checking on 'dir' too. Finally, document the behaviour of the hook. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: <linux-fbdev@vger.kernel.org> Cc: <linux-usb@vger.kernel.org> Cc: <linux-parisc@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, convert more macros to functionsJiri Slaby
Namely convert: * IS_FG -> con_is_fg * DO_UPDATE -> con_should_update * CON_IS_VISIBLE -> con_is_visible DO_UPDATE was a weird name for a yes/no answer, so the new name is con_should_update. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: linux-usb@vger.kernel.org Cc: linux-fbdev@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, remove consw->con_bmoveJiri Slaby
It is never called since commit 81732c3b2fede (tty vt: Fix line garbage in virtual console on command line edition) in 3.7. So remove all the callbacks. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: linux-usb@vger.kernel.org Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-fbdev@vger.kernel.org Cc: linux-parisc@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, consw->con_set_palette cleanupJiri Slaby
* allow NULL consw->con_set_palette (some consoles define an empty hook) * => remove empty hooks now * return value of consw->con_set_palette is never checked => make the function void * document consw->con_set_palette a bit Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: linux-usb@vger.kernel.org Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-fbdev@vger.kernel.org Cc: linux-parisc@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, consw->con_scrolldelta cleanupJiri Slaby
* allow NULL consw->con_scrolldelta (some consoles define an empty hook) * => remove empty hooks now * return value of consw->con_scrolldelta is never checked => make the function void * document consw->con_scrolldelta a bit Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: linux-usb@vger.kernel.org Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-fbdev@vger.kernel.org Cc: linux-parisc@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30tty: vt, make color_table constJiri Slaby
This means all ->con_set_palette have to have the second parameter const too now. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-22video/console: Resolve several shadow warningsMark Rustad
Resolve shadow warnings that appear in W=2 builds by renaming the "state" global to "vgastate". Signed-off-by: Mark Rustad <mark.d.rustad@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2014-06-19Merge tag 'drm-intel-fixes-2014-06-17' of ↵Dave Airlie
git://anongit.freedesktop.org/drm-intel into drm-next First round of fixes for 3.16-rc, mostly cc: stable, and the vt/vgacon fixes from Daniel [1] to avoid hangs and unclaimed register errors on module load/reload. * tag 'drm-intel-fixes-2014-06-17' of git://anongit.freedesktop.org/drm-intel: drm/i915/bdw: remove erroneous chv specific workarounds from bdw code drm/i915: fix possible refcount leak when resetting forcewake drm/i915: Reorder semaphore deadlock check drm/i95: Initialize active ring->pid to -1 drm/i915: set backlight duty cycle after backlight enable for gen4 drm/i915: Avoid div-by-zero when pixel_multiplier is zero drm/i915: Disable FBC by default also on Haswell and later drm/i915: Kick out vga console drm/i915: Fixup global gtt cleanup vt: Don't ignore unbind errors in vt_unbind vt: Fix up unregistration of vt drivers vt: Fix replacement console check when unbinding
2014-06-09drm/i915: Kick out vga consoleDaniel Vetter
Touching the VGA resources on an IVB EFI machine causes hard hangs when we then kick out the efifb. Ouch. Apparently this also prevents unclaimed register errors on hsw and hard machine hangs on my i855gm when trying to unbind fbcon. Also, we want this to make I915_FBDEV=n safe. v2: Rebase and pimp commit message. v3: We also need to unregister the vga console, otherwise the unbind of the fb console before module unload might resurrect it again. v4: Ignore errors when the vga console is already unregistered - this can happen when e.g. reloading i915.ko. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67813 Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: linux-fbdev@vger.kernel.org Cc: Jani Nikula <jani.nikula@linux.intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> (v1) Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-05-28console: Use explicit pointer type for vc_uni_pagedir* fieldsTakashi Iwai
The vc_data.vc_uni_pagedir filed is currently long int, supposedly to be served generically. This, however, leads to lots of cast to pointer, and rather it worsens the readability significantly. Actually, we have now only a single uni_pagedir map implementation, and this won't change likely. So, it'd be much more simple and error-prone to just use the exact pointer for struct uni_pagedir instead of long. Ditto for vc_uni_pagedir_loc. It's a pointer to the uni_pagedir, thus it can be changed similarly to the exact type. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28vgacon: Fix & cleanup refcountingTakashi Iwai
The vgacon driver prepares a two element array of uni_pagedir_loc and uses the second item as its own reference counter for sharing the uni_pagedir. And the code assumes blindly that the second item is available if the assigned vc_uni_pagedir isn't the standard one, which might be wrong (although currently it's so). This patch fixes that wrong assumption, and gives a slight cleanup along with it: namely, instead of array, just give the uni_pagedir_loc and a separate refcount variable. It makes the code a bit more understandable at first glance. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-27vgacon: fix missing include.Dave Airlie
This fixes the build error. Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-06-26vgacon.c: add cond reschedule points in vgacon_do_font_opMarcelo Tosatti
Booting a 64-vcpu KVM guest, with CONFIG_PREEMPT_VOLUNTARY, can result in a soft lockup: BUG: soft lockup - CPU#41 stuck for 67s! [setfont:1505] RIP: 0010:[<ffffffff812c48da>] [<ffffffff812c48da>] vgacon_do_font_op.clone.0+0x1ba/0x550 This is due to the 8192 (cmapsz) IO operations taking longer than expected due to lock contention in QEMU. Add conditional resched points in between writes allowing other tasks to execute. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-02-07vgacon/vt: clear buffer attributes when we load a 512 character font (v2)Dave Airlie
When we switch from 256->512 byte font rendering mode, it means the current contents of the screen is being reinterpreted. The bit that holds the high bit of the 9-bit font, may have been previously set, and thus the new font misrenders. The problem case we see is grub2 writes spaces with the bit set, so it ends up with data like 0x820, which gets reinterpreted into 0x120 char which the font translates into G with a circumflex. This flashes up on screen at boot and is quite ugly. A current side effect of this patch though is that any rendering on the screen changes color to a slightly darker color, but at least the screen no longer corrupts. v2: as suggested by hpa, always clear the attribute space, whether we are are going to or from 512 chars. Cc: stable@vger.kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-09-13locking, video: Annotate vga console lock as rawThomas Gleixner
The vga_lock lock can be taken in atomic context and therefore cannot be preempted on -rt - annotate it. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-25video: fix some comments in drivers/video/console/vgacon.cAmerigo Wang
Now vgacon_scrollback_startup() uses slab, not bootmem, the comment above it is obsolete, so does __init_refok. Signed-off-by: WANG Cong <amwang@redhat.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2011-01-13vgacon: check for efi machineYannick Heneault
It seems there is a small problem of VGA palette corruption on EFI machine. When the kernel initializes the architecture, it checks if the machine is a EFI machine and assumes that a VGA console can exist. When it initializes the console in vgacon_startup it checks if it can really use the VGA console. I think this is where a check is missing. Currently, the function can fail if a VESA boot mode is detected but not if a EFI boot mode was used. Thus vgacon_startup() doesn't fail and initialize the video card for a real VGA mode. This function changes the first 16entries of the VGA palette. When the efifb driver kicks in, the palette is not restored to default ramp value, thus the 16 first entry remain in a modified state. The following patch prevent this corruption. Signed-off-by: Yannick Heneault <yheneaul@matrox.com> Cc: Dave Airlie <airlied@linux.ie> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-17BKL: remove extraneous #include <smp_lock.h>Arnd Bergmann
The big kernel lock has been removed from all these files at some point, leaving only the #include. Remove this too as a cleanup. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-10tty: fix console_sem lock orderArnd Bergmann
vgacon_do_font_op releases and reacquires the BTM while holding console_sem. This violates the rule that BTM has to be the outer lock whenever we hold both. There does not seem to be any reason to give up the BTM here, so just stop doing that. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10tty: replace BKL with a new tty_lockArnd Bergmann
As a preparation for replacing the big kernel lock in the TTY layer, wrap all the callers in new macros tty_lock, tty_lock_nested and tty_unlock. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-06console/vgacon.c: mark file-local symbol staticThiago Farina
warning: symbol 'vgacon_text_mode_force' was not declared. Should it be static? Signed-off-by: Thiago Farina <tfransosi@gmail.com> Acked-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>