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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/x86/include/asm/nops.h
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/include/asm/nops.h')
-rw-r--r--arch/x86/include/asm/nops.h89
1 files changed, 89 insertions, 0 deletions
diff --git a/arch/x86/include/asm/nops.h b/arch/x86/include/asm/nops.h
new file mode 100644
index 0000000000..1c1b7550fa
--- /dev/null
+++ b/arch/x86/include/asm/nops.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_NOPS_H
+#define _ASM_X86_NOPS_H
+
+#include <asm/asm.h>
+
+/*
+ * Define nops for use with alternative() and for tracing.
+ */
+
+#ifndef CONFIG_64BIT
+
+/*
+ * Generic 32bit nops from GAS:
+ *
+ * 1: nop
+ * 2: movl %esi,%esi
+ * 3: leal 0x0(%esi),%esi
+ * 4: leal 0x0(%esi,%eiz,1),%esi
+ * 5: leal %ds:0x0(%esi,%eiz,1),%esi
+ * 6: leal 0x0(%esi),%esi
+ * 7: leal 0x0(%esi,%eiz,1),%esi
+ * 8: leal %ds:0x0(%esi,%eiz,1),%esi
+ *
+ * Except 5 and 8, which are DS prefixed 4 and 7 resp, where GAS would emit 2
+ * nop instructions.
+ */
+#define BYTES_NOP1 0x90
+#define BYTES_NOP2 0x89,0xf6
+#define BYTES_NOP3 0x8d,0x76,0x00
+#define BYTES_NOP4 0x8d,0x74,0x26,0x00
+#define BYTES_NOP5 0x3e,BYTES_NOP4
+#define BYTES_NOP6 0x8d,0xb6,0x00,0x00,0x00,0x00
+#define BYTES_NOP7 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00
+#define BYTES_NOP8 0x3e,BYTES_NOP7
+
+#define ASM_NOP_MAX 8
+
+#else
+
+/*
+ * Generic 64bit nops from GAS:
+ *
+ * 1: nop
+ * 2: osp nop
+ * 3: nopl (%eax)
+ * 4: nopl 0x00(%eax)
+ * 5: nopl 0x00(%eax,%eax,1)
+ * 6: osp nopl 0x00(%eax,%eax,1)
+ * 7: nopl 0x00000000(%eax)
+ * 8: nopl 0x00000000(%eax,%eax,1)
+ * 9: cs nopl 0x00000000(%eax,%eax,1)
+ * 10: osp cs nopl 0x00000000(%eax,%eax,1)
+ * 11: osp osp cs nopl 0x00000000(%eax,%eax,1)
+ */
+#define BYTES_NOP1 0x90
+#define BYTES_NOP2 0x66,BYTES_NOP1
+#define BYTES_NOP3 0x0f,0x1f,0x00
+#define BYTES_NOP4 0x0f,0x1f,0x40,0x00
+#define BYTES_NOP5 0x0f,0x1f,0x44,0x00,0x00
+#define BYTES_NOP6 0x66,BYTES_NOP5
+#define BYTES_NOP7 0x0f,0x1f,0x80,0x00,0x00,0x00,0x00
+#define BYTES_NOP8 0x0f,0x1f,0x84,0x00,0x00,0x00,0x00,0x00
+#define BYTES_NOP9 0x2e,BYTES_NOP8
+#define BYTES_NOP10 0x66,BYTES_NOP9
+#define BYTES_NOP11 0x66,BYTES_NOP10
+
+#define ASM_NOP9 _ASM_BYTES(BYTES_NOP9)
+#define ASM_NOP10 _ASM_BYTES(BYTES_NOP10)
+#define ASM_NOP11 _ASM_BYTES(BYTES_NOP11)
+
+#define ASM_NOP_MAX 11
+
+#endif /* CONFIG_64BIT */
+
+#define ASM_NOP1 _ASM_BYTES(BYTES_NOP1)
+#define ASM_NOP2 _ASM_BYTES(BYTES_NOP2)
+#define ASM_NOP3 _ASM_BYTES(BYTES_NOP3)
+#define ASM_NOP4 _ASM_BYTES(BYTES_NOP4)
+#define ASM_NOP5 _ASM_BYTES(BYTES_NOP5)
+#define ASM_NOP6 _ASM_BYTES(BYTES_NOP6)
+#define ASM_NOP7 _ASM_BYTES(BYTES_NOP7)
+#define ASM_NOP8 _ASM_BYTES(BYTES_NOP8)
+
+#ifndef __ASSEMBLY__
+extern const unsigned char * const x86_nops[];
+#endif
+
+#endif /* _ASM_X86_NOPS_H */