| Message ID | 20240304083333.449322-1-xin@zytor.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | c416b5bac6ad6ffe21e36225553b82ff2ec1558c |
| Headers | show |
| Series | [v2,1/1] x86/fred: Fix init_task thread stack pointer initialization | expand |
On 3/4/2024 12:33 AM, Xin Li (Intel) wrote: > As TOP_OF_KERNEL_STACK_PADDING is defined as 0 on x86_64, no one noticed > it's missing in the calculation of the .sp field in INIT_THREAD until it > is defined to 16 with CONFIG_X86_FRED=y. > > Subtract TOP_OF_KERNEL_STACK_PADDING from the .sp field of INIT_THREAD. > > 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> > Closes: https://lore.kernel.org/oe-lkp/202402262159.183c2a37-lkp@intel.com > Signed-off-by: Xin Li (Intel) <xin@zytor.com> > --- Should this fix, if it looks good, be included for the coming merge window? Thanks! Xin > > Change Since v1: > * Apply offset TOP_OF_KERNEL_STACK_PADDING to all uses of __end_init_task > (Brian Gerst). > --- > arch/x86/include/asm/processor.h | 6 ++++-- > arch/x86/kernel/head_64.S | 3 ++- > 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. > * > > base-commit: e13841907b8fda0ae0ce1ec03684665f578416a8
On March 6, 2024 10:28:25 AM PST, Xin Li <xin@zytor.com> wrote: >On 3/4/2024 12:33 AM, Xin Li (Intel) wrote: >> As TOP_OF_KERNEL_STACK_PADDING is defined as 0 on x86_64, no one noticed >> it's missing in the calculation of the .sp field in INIT_THREAD until it >> is defined to 16 with CONFIG_X86_FRED=y. >> >> Subtract TOP_OF_KERNEL_STACK_PADDING from the .sp field of INIT_THREAD. >> >> 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> >> Closes: https://lore.kernel.org/oe-lkp/202402262159.183c2a37-lkp@intel.com >> Signed-off-by: Xin Li (Intel) <xin@zytor.com> >> --- > >Should this fix, if it looks good, be included for the coming merge >window? > >Thanks! > Xin > >> >> Change Since v1: >> * Apply offset TOP_OF_KERNEL_STACK_PADDING to all uses of __end_init_task >> (Brian Gerst). >> --- >> arch/x86/include/asm/processor.h | 6 ++++-- >> arch/x86/kernel/head_64.S | 3 ++- >> 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. >> * >> >> base-commit: e13841907b8fda0ae0ce1ec03684665f578416a8 > Absolutely.
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. *
As TOP_OF_KERNEL_STACK_PADDING is defined as 0 on x86_64, no one noticed it's missing in the calculation of the .sp field in INIT_THREAD until it is defined to 16 with CONFIG_X86_FRED=y. Subtract TOP_OF_KERNEL_STACK_PADDING from the .sp field of INIT_THREAD. 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> Closes: https://lore.kernel.org/oe-lkp/202402262159.183c2a37-lkp@intel.com Signed-off-by: Xin Li (Intel) <xin@zytor.com> --- Change Since v1: * Apply offset TOP_OF_KERNEL_STACK_PADDING to all uses of __end_init_task (Brian Gerst). --- arch/x86/include/asm/processor.h | 6 ++++-- arch/x86/kernel/head_64.S | 3 ++- arch/x86/xen/xen-head.S | 2 +- 3 files changed, 7 insertions(+), 4 deletions(-) base-commit: e13841907b8fda0ae0ce1ec03684665f578416a8