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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /arch/x86/boot/video-bios.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'arch/x86/boot/video-bios.c')
-rw-r--r--arch/x86/boot/video-bios.c126
1 files changed, 126 insertions, 0 deletions
diff --git a/arch/x86/boot/video-bios.c b/arch/x86/boot/video-bios.c
new file mode 100644
index 000000000..6eb8c06bc
--- /dev/null
+++ b/arch/x86/boot/video-bios.c
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright 2007 rPath, Inc. - All Rights Reserved
+ * Copyright 2009 Intel Corporation; author H. Peter Anvin
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * Standard video BIOS modes
+ *
+ * We have two options for this; silent and scanned.
+ */
+
+#include "boot.h"
+#include "video.h"
+
+static __videocard video_bios;
+
+/* Set a conventional BIOS mode */
+static int set_bios_mode(u8 mode);
+
+static int bios_set_mode(struct mode_info *mi)
+{
+ return set_bios_mode(mi->mode - VIDEO_FIRST_BIOS);
+}
+
+static int set_bios_mode(u8 mode)
+{
+ struct biosregs ireg, oreg;
+ u8 new_mode;
+
+ initregs(&ireg);
+ ireg.al = mode; /* AH=0x00 Set Video Mode */
+ intcall(0x10, &ireg, NULL);
+
+ ireg.ah = 0x0f; /* Get Current Video Mode */
+ intcall(0x10, &ireg, &oreg);
+
+ do_restore = 1; /* Assume video contents were lost */
+
+ /* Not all BIOSes are clean with the top bit */
+ new_mode = oreg.al & 0x7f;
+
+ if (new_mode == mode)
+ return 0; /* Mode change OK */
+
+#ifndef _WAKEUP
+ if (new_mode != boot_params.screen_info.orig_video_mode) {
+ /* Mode setting failed, but we didn't end up where we
+ started. That's bad. Try to revert to the original
+ video mode. */
+ ireg.ax = boot_params.screen_info.orig_video_mode;
+ intcall(0x10, &ireg, NULL);
+ }
+#endif
+ return -1;
+}
+
+static int bios_probe(void)
+{
+ u8 mode;
+#ifdef _WAKEUP
+ u8 saved_mode = 0x03;
+#else
+ u8 saved_mode = boot_params.screen_info.orig_video_mode;
+#endif
+ u16 crtc;
+ struct mode_info *mi;
+ int nmodes = 0;
+
+ if (adapter != ADAPTER_EGA && adapter != ADAPTER_VGA)
+ return 0;
+
+ set_fs(0);
+ crtc = vga_crtc();
+
+ video_bios.modes = GET_HEAP(struct mode_info, 0);
+
+ for (mode = 0x14; mode <= 0x7f; mode++) {
+ if (!heap_free(sizeof(struct mode_info)))
+ break;
+
+ if (mode_defined(VIDEO_FIRST_BIOS+mode))
+ continue;
+
+ if (set_bios_mode(mode))
+ continue;
+
+ /* Try to verify that it's a text mode. */
+
+ /* Attribute Controller: make graphics controller disabled */
+ if (in_idx(0x3c0, 0x10) & 0x01)
+ continue;
+
+ /* Graphics Controller: verify Alpha addressing enabled */
+ if (in_idx(0x3ce, 0x06) & 0x01)
+ continue;
+
+ /* CRTC cursor location low should be zero(?) */
+ if (in_idx(crtc, 0x0f))
+ continue;
+
+ mi = GET_HEAP(struct mode_info, 1);
+ mi->mode = VIDEO_FIRST_BIOS+mode;
+ mi->depth = 0; /* text */
+ mi->x = rdfs16(0x44a);
+ mi->y = rdfs8(0x484)+1;
+ nmodes++;
+ }
+
+ set_bios_mode(saved_mode);
+
+ return nmodes;
+}
+
+static __videocard video_bios =
+{
+ .card_name = "BIOS",
+ .probe = bios_probe,
+ .set_mode = bios_set_mode,
+ .unsafe = 1,
+ .xmode_first = VIDEO_FIRST_BIOS,
+ .xmode_n = 0x80,
+};