From 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 16 Aug 2026 15:32:33 +0200 Subject: kbuild: rust: keep Rust objects out of Clang LTO with inline helpers Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit `objtool` errors such as: vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a: can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd The reason is that in such builds, the Clang invocation that compiles the combined Rust plus helpers bitcode emits LLVM bitcode (again) -- the final code generation happens in the linker's LTO step, which the `-mllvm` trap options passed to Clang do not reach. This, in turn, means that unreachable traps are missing, and the impossible paths do not merely fallthrough to the next symbol, but past the end of their own section, since LTO builds place each function in its own section. Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always emits machine code directly, with the traps in place. Assisted-by: LLM Cc: Gary Guo Cc: Boqun Feng Cc: Alice Ryhl Cc: Matthew Maurer Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust") Acked-by: Gary Guo Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- drivers/video/fbdev/stifb.c | 1531 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1531 insertions(+) create mode 100644 drivers/video/fbdev/stifb.c (limited to 'drivers/video/fbdev/stifb.c') diff --git a/drivers/video/fbdev/stifb.c b/drivers/video/fbdev/stifb.c new file mode 100644 index 000000000..8e5bac275 --- /dev/null +++ b/drivers/video/fbdev/stifb.c @@ -0,0 +1,1531 @@ +/* + * linux/drivers/video/stifb.c - + * Low level Frame buffer driver for HP workstations with + * STI (standard text interface) video firmware. + * + * Copyright (C) 2001-2006 Helge Deller + * Portions Copyright (C) 2001 Thomas Bogendoerfer + * + * Based on: + * - linux/drivers/video/artistfb.c -- Artist frame buffer driver + * Copyright (C) 2000 Philipp Rumpf + * - based on skeletonfb, which was + * Created 28 Dec 1997 by Geert Uytterhoeven + * - HP Xhp cfb-based X11 window driver for XFree86 + * (c)Copyright 1992 Hewlett-Packard Co. + * + * + * The following graphics display devices (NGLE family) are supported by this driver: + * + * HPA4070A known as "HCRX", a 1280x1024 color device with 8 planes + * HPA4071A known as "HCRX24", a 1280x1024 color device with 24 planes, + * optionally available with a hardware accelerator as HPA4071A_Z + * HPA1659A known as "CRX", a 1280x1024 color device with 8 planes + * HPA1439A known as "CRX24", a 1280x1024 color device with 24 planes, + * optionally available with a hardware accelerator. + * HPA1924A known as "GRX", a 1280x1024 grayscale device with 8 planes + * HPA2269A known as "Dual CRX", a 1280x1024 color device with 8 planes, + * implements support for two displays on a single graphics card. + * HP710C internal graphics support optionally available on the HP9000s710 SPU, + * supports 1280x1024 color displays with 8 planes. + * HP710G same as HP710C, 1280x1024 grayscale only + * HP710L same as HP710C, 1024x768 color only + * HP712 internal graphics support on HP9000s712 SPU, supports 640x480, + * 1024x768 or 1280x1024 color displays on 8 planes (Artist) + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + */ + +/* TODO: + * - 1bpp mode is completely untested + * - add support for h/w acceleration + * - add hardware cursor + * - automatically disable double buffering (e.g. on RDI precisionbook laptop) + */ + + +/* on supported graphic devices you may: + * #define FALLBACK_TO_1BPP to fall back to 1 bpp, or + * #undef FALLBACK_TO_1BPP to reject support for unsupported cards */ +#undef FALLBACK_TO_1BPP + +#undef DEBUG_STIFB_REGS /* debug sti register accesses */ + + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include /* for HP-UX compatibility */ +#include + +#include