Re: [PATCH 6/6] fix Task State Segment layout for 64 bit

[Samuel Thibault]

Luca Dariz, le sam. 05 févr. 2022 18:51:29 +0100, a ecrit:
> Signed-off-by: Luca Dariz <luca@orpolo.org>

Applied, thanks!

> ---
>  i386/i386/i386asm.sym |  4 ++++
>  i386/i386/ktss.c      |  8 ++++++--
>  i386/i386/pcb.c       |  4 ++++
>  i386/i386/tss.h       | 24 ++++++++++++++++++++++--
>  4 files changed, 36 insertions(+), 4 deletions(-)
> 
> diff --git a/i386/i386/i386asm.sym b/i386/i386/i386asm.sym
> index 9e1d13d7..417c040d 100644
> --- a/i386/i386/i386asm.sym
> +++ b/i386/i386/i386asm.sym
> @@ -95,8 +95,12 @@ offset     i386_interrupt_state    i       eip
>  offset       i386_interrupt_state    i       cs
>  offset       i386_interrupt_state    i       efl
>  
> +#ifdef __x86_64__
> +offset       i386_tss                tss     rsp0
> +#else
>  offset       i386_tss                tss     esp0
>  offset       i386_tss                tss     ss0
> +#endif
>  
>  offset       machine_slot            sub_type        cpu_type
>  
> diff --git a/i386/i386/ktss.c b/i386/i386/ktss.c
> index 917e6305..24e12cf4 100644
> --- a/i386/i386/ktss.c
> +++ b/i386/i386/ktss.c
> @@ -55,11 +55,15 @@ ktss_init(void)
>       fill_gdt_sys_descriptor(KERNEL_TSS,
>                               kvtolin(&ktss), sizeof(struct task_tss) - 1,
>                               ACC_PL_K|ACC_TSS, 0);
> -
>       /* Initialize the master TSS.  */
> +#ifdef __x86_64__
> +     ktss.tss.rsp0 = (unsigned long)(exception_stack+1024);
> +     ktss.tss.io_bit_map_offset = IOPB_INVAL;
> +#else /* ! __x86_64__ */
>       ktss.tss.ss0 = KERNEL_DS;
>       ktss.tss.esp0 = (unsigned long)(exception_stack+1024);
> -     ktss.tss.io_bit_map_offset = IOPB_INVAL;                                
>                                                                 
> +     ktss.tss.io_bit_map_offset = IOPB_INVAL;
> +#endif /* __x86_64__ */
>       /* Set the last byte in the I/O bitmap to all 1's.  */
>       ktss.barrier = 0xff;
>  
> diff --git a/i386/i386/pcb.c b/i386/i386/pcb.c
> index 23585323..23b734e3 100644
> --- a/i386/i386/pcb.c
> +++ b/i386/i386/pcb.c
> @@ -153,7 +153,11 @@ void switch_ktss(pcb_t pcb)
>       if (hyp_stack_switch(KERNEL_DS, pcb_stack_top))
>               panic("stack_switch");
>  #else        /* MACH_RING1 */
> +#ifdef __x86_64__
> +        curr_ktss(mycpu)->tss.rsp0 = pcb_stack_top;
> +#else /* __x86_64__ */
>       curr_ktss(mycpu)->tss.esp0 = pcb_stack_top;
> +#endif /* __x86_64__ */
>  #endif       /* MACH_RING1 */
>      }
>  
> diff --git a/i386/i386/tss.h b/i386/i386/tss.h
> index ff25f217..31e1f5cb 100644
> --- a/i386/i386/tss.h
> +++ b/i386/i386/tss.h
> @@ -27,13 +27,33 @@
>  #ifndef      _I386_TSS_H_
>  #define      _I386_TSS_H_
>  
> +#include <sys/types.h>
>  #include <mach/inline.h>
>  
>  #include <machine/io_perm.h>
>  
>  /*
> - *   i386 Task State Segment
> + *   x86 Task State Segment
>   */
> +#ifdef __x86_64__
> +struct i386_tss {
> +  uint32_t _reserved0;
> +  uint64_t rsp0;
> +  uint64_t rsp1;
> +  uint64_t rsp2;
> +  uint64_t _reserved1;
> +  uint64_t ist1;
> +  uint64_t ist2;
> +  uint64_t ist3;
> +  uint64_t ist4;
> +  uint64_t ist5;
> +  uint64_t ist6;
> +  uint64_t ist7;
> +  uint64_t _reserved2;
> +  uint16_t _reserved3;
> +  uint16_t io_bit_map_offset;
> +} __attribute__((__packed__));
> +#else /* ! __x86_64__ */
>  struct i386_tss {
>       int             back_link;      /* segment number of previous task,
>                                          if nested */
> @@ -67,7 +87,7 @@ struct i386_tss {
>                                       /* offset to start of IO permission
>                                          bit map */
>  };
> -
> +#endif /* __x86_64__ */
>  
>  /* The structure extends the above TSS structure by an I/O permission bitmap
>     and the barrier.  */
> -- 
> 2.30.2
> 
> 

-- 
Samuel
---
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