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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 /drivers/video/console/dummycon.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 'drivers/video/console/dummycon.c')
-rw-r--r--drivers/video/console/dummycon.c159
1 files changed, 159 insertions, 0 deletions
diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c
new file mode 100644
index 000000000..7d02470f1
--- /dev/null
+++ b/drivers/video/console/dummycon.c
@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/drivers/video/dummycon.c -- A dummy console driver
+ *
+ * To be used if there's no other console driver (e.g. for plain VGA text)
+ * available, usually until fbcon takes console over.
+ */
+
+#include <linux/types.h>
+#include <linux/kdev_t.h>
+#include <linux/console.h>
+#include <linux/vt_kern.h>
+#include <linux/screen_info.h>
+#include <linux/init.h>
+#include <linux/module.h>
+
+/*
+ * Dummy console driver
+ */
+
+#if defined(CONFIG_ARCH_FOOTBRIDGE) && defined(CONFIG_VGA_CONSOLE)
+#include <asm/vga.h>
+#define DUMMY_COLUMNS vgacon_screen_info.orig_video_cols
+#define DUMMY_ROWS vgacon_screen_info.orig_video_lines
+#else
+/* set by Kconfig. Use 80x25 for 640x480 and 160x64 for 1280x1024 */
+#define DUMMY_COLUMNS CONFIG_DUMMY_CONSOLE_COLUMNS
+#define DUMMY_ROWS CONFIG_DUMMY_CONSOLE_ROWS
+#endif
+
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER
+/* These are both protected by the console_lock */
+static RAW_NOTIFIER_HEAD(dummycon_output_nh);
+static bool dummycon_putc_called;
+
+void dummycon_register_output_notifier(struct notifier_block *nb)
+{
+ WARN_CONSOLE_UNLOCKED();
+
+ raw_notifier_chain_register(&dummycon_output_nh, nb);
+
+ if (dummycon_putc_called)
+ nb->notifier_call(nb, 0, NULL);
+}
+
+void dummycon_unregister_output_notifier(struct notifier_block *nb)
+{
+ WARN_CONSOLE_UNLOCKED();
+
+ raw_notifier_chain_unregister(&dummycon_output_nh, nb);
+}
+
+static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y,
+ unsigned int x)
+{
+ WARN_CONSOLE_UNLOCKED();
+
+ dummycon_putc_called = true;
+ raw_notifier_call_chain(&dummycon_output_nh, 0, NULL);
+}
+
+static void dummycon_putcs(struct vc_data *vc, const u16 *s, unsigned int count,
+ unsigned int ypos, unsigned int xpos)
+{
+ unsigned int i;
+
+ if (!dummycon_putc_called) {
+ /* Ignore erases */
+ for (i = 0 ; i < count; i++) {
+ if (s[i] != vc->vc_video_erase_char)
+ break;
+ }
+ if (i == count)
+ return;
+
+ dummycon_putc_called = true;
+ }
+
+ raw_notifier_call_chain(&dummycon_output_nh, 0, NULL);
+}
+
+static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
+ bool mode_switch)
+{
+ /* Redraw, so that we get putc(s) for output done while blanked */
+ return true;
+}
+
+static bool dummycon_switch(struct vc_data *vc)
+{
+ /*
+ * Redraw, so that we get putc(s) for output done while switched
+ * away. Informs deferred consoles to take over the display.
+ */
+ return true;
+}
+#else
+static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y,
+ unsigned int x) { }
+static void dummycon_putcs(struct vc_data *vc, const u16 *s, unsigned int count,
+ unsigned int ypos, unsigned int xpos) { }
+static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
+ bool mode_switch)
+{
+ return false;
+}
+static bool dummycon_switch(struct vc_data *vc)
+{
+ return false;
+}
+#endif
+
+static const char *dummycon_startup(void)
+{
+ return "dummy device";
+}
+
+static void dummycon_init(struct vc_data *vc, bool init)
+{
+ vc->vc_can_do_color = 1;
+ if (init) {
+ vc->vc_cols = DUMMY_COLUMNS;
+ vc->vc_rows = DUMMY_ROWS;
+ } else
+ vc_resize(vc, DUMMY_COLUMNS, DUMMY_ROWS);
+}
+
+static void dummycon_deinit(struct vc_data *vc) { }
+static void dummycon_clear(struct vc_data *vc, unsigned int sy, unsigned int sx,
+ unsigned int width) { }
+static void dummycon_cursor(struct vc_data *vc, bool enable) { }
+
+static bool dummycon_scroll(struct vc_data *vc, unsigned int top,
+ unsigned int bottom, enum con_scroll dir,
+ unsigned int lines)
+{
+ return false;
+}
+
+/*
+ * The console `switch' structure for the dummy console
+ *
+ * Most of the operations are dummies.
+ */
+
+const struct consw dummy_con = {
+ .owner = THIS_MODULE,
+ .con_startup = dummycon_startup,
+ .con_init = dummycon_init,
+ .con_deinit = dummycon_deinit,
+ .con_clear = dummycon_clear,
+ .con_putc = dummycon_putc,
+ .con_putcs = dummycon_putcs,
+ .con_cursor = dummycon_cursor,
+ .con_scroll = dummycon_scroll,
+ .con_switch = dummycon_switch,
+ .con_blank = dummycon_blank,
+};
+EXPORT_SYMBOL_GPL(dummy_con);