diff options
| author |   Xin Li (Intel) <xin@zytor.com> | 2024-03-04 00:33:33 -0800 |
|---|---|---|
| committer |   Thomas Gleixner <tglx@linutronix.de> | 2024-03-07 11:55:36 +0100 |
| commit | c416b5bac6ad6ffe21e36225553b82ff2ec1558c (patch) | |
| tree | 46827e73fce51e923a6015cd74b7fe1904f91577 /arch/x86 | |
| parent | MAINTAINERS: Add a maintainer entry for FRED (diff) | |
| download | wireguard-linux-c416b5bac6ad6ffe21e36225553b82ff2ec1558c.tar.xz wireguard-linux-c416b5bac6ad6ffe21e36225553b82ff2ec1558c.zip | |
x86/fred: Fix init_task thread stack pointer initialization
As TOP_OF_KERNEL_STACK_PADDING was defined as 0 on x86_64, it went
unnoticed that the initialization of the .sp field in INIT_THREAD and some
calculations in the low level startup code do not take the padding into
account.
FRED enabled kernels require a 16 byte padding, which means that the init
task initialization and the low level startup code use the wrong stack
offset.
Subtract TOP_OF_KERNEL_STACK_PADDING in all affected places to adjust for
this.
Fixes: 65c9cc9e2c14 ("x86/fred: Reserve space for the FRED stack frame")
Fixes: 3adee777ad0d ("x86/smpboot: Remove initial_stack on 64-bit")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Closes: https://lore.kernel.org/oe-lkp/202402262159.183c2a37-lkp@intel.com
Link: https://lore.kernel.org/r/20240304083333.449322-1-xin@zytor.com
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/include/asm/processor.h | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/head_64.S | 3 | ||||
| -rw-r--r-- | arch/x86/xen/xen-head.S | 2 |
3 files changed, 7 insertions, 4 deletions
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 26620d7642a9..17fe81998ce4 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -664,8 +664,10 @@ static __always_inline void prefetchw(const void *x) #else extern unsigned long __end_init_task[]; -#define INIT_THREAD { \ - .sp = (unsigned long)&__end_init_task - sizeof(struct pt_regs), \ +#define INIT_THREAD { \ + .sp = (unsigned long)&__end_init_task - \ + TOP_OF_KERNEL_STACK_PADDING - \ + sizeof(struct pt_regs), \ } extern unsigned long KSTK_ESP(struct task_struct *task); diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index d4918d03efb4..c38e43589046 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -26,6 +26,7 @@ #include <asm/apicdef.h> #include <asm/fixmap.h> #include <asm/smp.h> +#include <asm/thread_info.h> /* * We are not able to switch in one step to the final KERNEL ADDRESS SPACE @@ -66,7 +67,7 @@ SYM_CODE_START_NOALIGN(startup_64) mov %rsi, %r15 /* Set up the stack for verify_cpu() */ - leaq (__end_init_task - PTREGS_SIZE)(%rip), %rsp + leaq (__end_init_task - TOP_OF_KERNEL_STACK_PADDING - PTREGS_SIZE)(%rip), %rsp leaq _text(%rip), %rdi diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S index a0ea285878db..04101b984f24 100644 --- a/arch/x86/xen/xen-head.S +++ b/arch/x86/xen/xen-head.S @@ -49,7 +49,7 @@ SYM_CODE_START(startup_xen) ANNOTATE_NOENDBR cld - leaq (__end_init_task - PTREGS_SIZE)(%rip), %rsp + leaq (__end_init_task - TOP_OF_KERNEL_STACK_PADDING - PTREGS_SIZE)(%rip), %rsp /* Set up %gs. * |