stos: Add kernel knotting impl

Signed-off-by: Chloe M. <chloe@mensia.org>
2026-06-23 05:36:10 +00:00
parent d2596979a2
commit 81d5f13a30
4 changed files with 136 additions and 1 deletions
@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description:  Fucks and knots the kernel
+ * Author:       Chloe M.
+ */
+
+    .text
+    .globl KeKnot
+KeKnot:
+    /*
+     * When we are called here, the kernel is to be fucked with
+     * the most love and care we can put out before we knot it
+     * and fill it with warm cum...
+     */
+
+    cli    /* Don't get interrupted */
+    cld    /* Just in case */
+
+    /*
+     * We don't want another processor to attempt to fuck the kernel
+     * while we are already knotting it to avoid it becoming too
+     * cumdrunk and misbehaving further. If another processor attempts
+     * to do so, knot and lock them hard, because that's what needy
+     * cores get :3
+     */
+    mov $1, %rax            /* Prepare the lock */
+    xchg %rax, MpLock       /* Ah!~ Fuck~ @.@ */
+    or %rax, %rax           /* Are we another core? */
+    jnz 1f
+
+    /*
+     * The kernel is being extra needy and may or may not have
+     * kicked its paws into its stack. It's okay little kernel,
+     * we'll give you a new stack that's safe and cozy to lay in
+     * before the knotting begins!
+     */
+    lea KnotStackTop(%rip), %rsp
+
+    call KiKnot             /* Enter the main knot handler */
+1:  mfence                  /* Drain those caches~ */
+.Lock:
+    cli                     /* Don't get interrupted */
+    hlt                     /* Get knotted >:3 */
+    jmp .Lock
+
+    .section .data
+MpLock: .quad 0
+KnotStack: .fill 4096, 1, 0
+KnotStackTop:
@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description:  Fucks and knots the kernel
+ * Author:       Chloe M.
+ */
+
+#ifndef _KE_KNOT_H_
+#define _KE_KNOT_H_ 1
+
+#include <stdef.h>
+
+/*
+ * Valid knot reasons
+ *
+ * @KNOT_MISC:          Misc. reason
+ * @KNOT_UNBOUND_RSRC:  Unbounded resource
+ */
+typedef enum {
+    KNOT_MISC,
+    KNOT_UNBOUND_RSRC
+} KNOT_REASON;
+
+/*
+ * Fuck and knot the kernel if it is misbehaving
+ *
+ * @Reason: Reason of knotting
+ * @Fmt:    Format string
+ * @<...>:  Variadic arguments
+ */
+VOID KeKnot(KNOT_REASON Reason, const char *Fmt, ...);
+
+#endif  /* !_KE_KNOT_H_ */
@@ -9,7 +9,8 @@
 .SILENT:
 include ../../mk/stos.mk

-CFILES = $(shell find ../init -name "*.c")
+CFILES = $(shell ls)
+CFILES += $(shell find ../init -name "*.c")
 CFILES += $(shell find ../xt -name "*.c")
 CFILES += $(shell find ../lib -name "*.c")
 CFILES += $(shell find ../drivers -name "*.c")
@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description:  Fucks and knots the kernel
+ * Author:       Chloe M.
+ */
+
+#include <drivers/bootvid/fbio.h>
+#include <ex/trace.h>
+#include <ke/knot.h>
+
+#define KNOT_REASON(Reason)             \
+    ((Reason) >= NELEM(ReasonTable))    \
+        ? ReasonTable[0]                \
+        : ReasonTable[(Reason)]
+
+/* Reason lookup table */
+static const CHAR *ReasonTable[] = {
+    [KNOT_MISC] = "unspecified reason",
+    [KNOT_UNBOUND_RSRC] = "unbounded resource"
+};
+
+/* Globals */
+static CHAR KnotBuf[256];
+static va_list Ap;
+static BOOTCONS_ATTR KnotAttr = {
+    .Background = 0x000080,
+    .Foreground = 0xFFFFFF
+};
+
+static CHAR KnotMessage[] = {
+    "SystemPaw DR has ran into a wittle issue and the kernel pilot kitty\n"
+    "has suspended the CPU to prevent damage to your machine.\n\n"
+    "Press and hold the power button until the screen blanks.\n\n"
+};
+
+VOID
+KiKnot(KNOT_REASON Reason, const CHAR *Fmt, ...)
+{
+    va_start(Ap, Fmt);
+    FmtPrintf(KnotBuf, sizeof(KnotBuf), Fmt, Ap);
+    BootVidInitCons(&KnotAttr);
+
+    TRACE("\033[H\033[2J");
+    TRACE(KnotMessage);
+    TRACE("knot: %s", KnotBuf);
+    TRACE("reason: %s\n", KNOT_REASON(Reason));
+}