[PATCH v13 15/35] x86/fred: Add a new header file for FRED definitions
From: Xin Li <hidden>
Date: 2023-12-05 11:22:24
Also in:
kvm, linux-doc, linux-edac, lkml, xen-devel
Subsystem:
intel(r) flexible return and event delivery, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Xin Li, "H. Peter Anvin", Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: "H. Peter Anvin (Intel)" <hpa@zytor.com> Add a header file for FRED prototypes and definitions. Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Tested-by: Shan Kang <redacted> Signed-off-by: Xin Li <redacted> --- Changes since v6: * Replace pt_regs csx flags prefix FRED_CSL_ with FRED_CSX_. --- arch/x86/include/asm/fred.h | 68 +++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 arch/x86/include/asm/fred.h
diff --git a/arch/x86/include/asm/fred.h b/arch/x86/include/asm/fred.h
new file mode 100644
index 000000000000..f514fdb5a39f
--- /dev/null
+++ b/arch/x86/include/asm/fred.h@@ -0,0 +1,68 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Macros for Flexible Return and Event Delivery (FRED) + */ + +#ifndef ASM_X86_FRED_H +#define ASM_X86_FRED_H + +#include <linux/const.h> + +#include <asm/asm.h> + +/* + * FRED event return instruction opcodes for ERET{S,U}; supported in + * binutils >= 2.41. + */ +#define ERETS _ASM_BYTES(0xf2,0x0f,0x01,0xca) +#define ERETU _ASM_BYTES(0xf3,0x0f,0x01,0xca) + +/* + * RSP is aligned to a 64-byte boundary before used to push a new stack frame + */ +#define FRED_STACK_FRAME_RSP_MASK _AT(unsigned long, (~0x3f)) + +/* + * Used for the return address for call emulation during code patching, + * and measured in 64-byte cache lines. + */ +#define FRED_CONFIG_REDZONE_AMOUNT 1 +#define FRED_CONFIG_REDZONE (_AT(unsigned long, FRED_CONFIG_REDZONE_AMOUNT) << 6) +#define FRED_CONFIG_INT_STKLVL(l) (_AT(unsigned long, l) << 9) +#define FRED_CONFIG_ENTRYPOINT(p) _AT(unsigned long, (p)) + +#ifndef __ASSEMBLY__ + +#ifdef CONFIG_X86_FRED +#include <linux/kernel.h> + +#include <asm/ptrace.h> + +struct fred_info { + /* Event data: CR2, DR6, ... */ + unsigned long edata; + unsigned long resv; +}; + +/* Full format of the FRED stack frame */ +struct fred_frame { + struct pt_regs regs; + struct fred_info info; +}; + +static __always_inline struct fred_info *fred_info(struct pt_regs *regs) +{ + return &container_of(regs, struct fred_frame, regs)->info; +} + +static __always_inline unsigned long fred_event_data(struct pt_regs *regs) +{ + return fred_info(regs)->edata; +} + +#else /* CONFIG_X86_FRED */ +static __always_inline unsigned long fred_event_data(struct pt_regs *regs) { return 0; } +#endif /* CONFIG_X86_FRED */ +#endif /* !__ASSEMBLY__ */ + +#endif /* ASM_X86_FRED_H */
--
2.43.0