x86/fred: Reserve space for the FRED stack frame

When using FRED, reserve space at the top of the stack frame, just
like i386 does.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Shan Kang <shan.kang@intel.com>
Link: https://lore.kernel.org/r/20231205105030.8698-17-xin3.li@intel.com
This commit is contained in:
H. Peter Anvin (Intel) 2023-12-05 02:50:05 -08:00 committed by Borislav Petkov (AMD)
parent 32b09c2303
commit 65c9cc9e2c

View File

@ -31,7 +31,9 @@
* In vm86 mode, the hardware frame is much longer still, so add 16 * In vm86 mode, the hardware frame is much longer still, so add 16
* bytes to make room for the real-mode segments. * bytes to make room for the real-mode segments.
* *
* x86_64 has a fixed-length stack frame. * x86-64 has a fixed-length stack frame, but it depends on whether
* or not FRED is enabled. Future versions of FRED might make this
* dynamic, but for now it is always 2 words longer.
*/ */
#ifdef CONFIG_X86_32 #ifdef CONFIG_X86_32
# ifdef CONFIG_VM86 # ifdef CONFIG_VM86
@ -39,8 +41,12 @@
# else # else
# define TOP_OF_KERNEL_STACK_PADDING 8 # define TOP_OF_KERNEL_STACK_PADDING 8
# endif # endif
#else #else /* x86-64 */
# define TOP_OF_KERNEL_STACK_PADDING 0 # ifdef CONFIG_X86_FRED
# define TOP_OF_KERNEL_STACK_PADDING (2 * 8)
# else
# define TOP_OF_KERNEL_STACK_PADDING 0
# endif
#endif #endif
/* /*