[Crash-utility] [PATCH] sadump: fix help -D lists, uninteresting register entries

[lijiang]

在 2020年10月07日 00:00, crash-utility-request at redhat.com 写道:
> Date: Tue,  6 Oct 2020 21:05:39 +0900
> From: HATAYAMA Daisuke <d.hatayama at fujitsu.com>
> To: crash-utility at redhat.com
> Cc: HATAYAMA Daisuke <d.hatayama at fujitsu.com>
> Subject: [Crash-utility] [PATCH] sadump: fix help -D lists
> 	uninteresting	register entries
> Message-ID: <1601985939-1431-1-git-send-email-d.hatayama at fujitsu.com>
> Content-Type: text/plain; charset="US-ASCII"
> 
> Reserved fields in SMRAM CPU states could be non-zero even if the
> corresponding APICs are NOT used. This breaks the assumption that
> SMRAM CPU state is zero cleared if and only if the APIC corresponding
> to the entry is NOT used. As the result, help -D lists uninteresting
> entries as below:
> 
>   APIC ID: 14
>       RIP: 0000000000000000 RSP: 0000000000000000 RBP: 0000000000000000
>       RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
>       RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
>       R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000
>       R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000
>       R14: 0000000000000000 R15: 0000000000000000
>       SMM REV: 00000000 SMM BASE 00000000
>       CS : 00000000 DS: 00000000 SS: 00000000 ES: 00000000 FS: 00000000
>       GS : 00000000
>       CR0: 0000000000000000 CR3: 0000000000000000 CR4: 00000000
>       GDT: 0000000000000000 LDT: 0000000000000000 IDT: 0000000000000000
>       GDTlim: 00000000 LDTlim: 00000000 IDTlim: 00000000
>       LDTR: 00000000 TR: 00000000 RFLAGS: 0000000000000000
>       EPTP: 0000000000000000 EPTP_SETTING: 00000000
>       DR6: 0000000000000000 DR7: 0000000000000000
>       Ia32Efer: 0000000000000000
>       IoMemAddr: 0000000000000000 IoEip: 0000000000000000
>       IoMisc: 00000000 LdtInfo: 00000000
>       IoInstructionRestart: 0000 AutoHaltRestart: 0000
> 
> To fix this issue, mask reserved fields before comparison.
> 
Thanks for the fix, HATAYAMA.

Acked-by: Lianbo Jiang <lijiang at redhat.com>


> Signed-off-by: HATAYAMA Daisuke <d.hatayama at fujitsu.com>
> ---
>  sadump.c | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/sadump.c b/sadump.c
> index 009e17a..f313528 100644
> --- a/sadump.c
> +++ b/sadump.c
> @@ -51,6 +51,7 @@ static int cpu_to_apicid(int cpu, int *apicid);
>  static int get_sadump_smram_cpu_state(int cpu, struct sadump_smram_cpu_state *smram);
>  static int block_table_init(void);
>  static uint64_t pfn_to_block(uint64_t pfn);
> +static void mask_reserved_fields(struct sadump_smram_cpu_state *smram);
>  
>  struct sadump_data *
>  sadump_get_sadump_data(void)
> @@ -1040,6 +1041,15 @@ int sadump_memory_dump(FILE *fp)
>  				      "cpu_state\n");
>  				return FALSE;
>  			}
> +			/*
> +			 * Reserved fields in SMRAM CPU states could
> +			 * be non-zero even if the corresponding APICs
> +			 * are NOT used. This breaks the assumption
> +			 * that SMRAM CPU state is zero cleared if and
> +			 * only if the APIC corresponding to the entry
> +			 * is NOT used.
> +			 */
> +			mask_reserved_fields(&scs);
>  			if (memcmp(&scs, &zero, sizeof(scs)) != 0) {
>  				fprintf(fp, "\n");
>  				display_smram_cpu_state(aid, &scs);
> @@ -1707,3 +1717,15 @@ sadump_get_cr3_idtr(ulong *cr3, ulong *idtr)
>  	return TRUE;
>  }
>  #endif /* X86_64 */
> +
> +static void
> +mask_reserved_fields(struct sadump_smram_cpu_state *smram)
> +{
> +	memset(smram->Reserved1, 0, sizeof(smram->Reserved1));
> +	memset(smram->Reserved2, 0, sizeof(smram->Reserved2));
> +	memset(smram->Reserved3, 0, sizeof(smram->Reserved3));
> +	memset(smram->Reserved4, 0, sizeof(smram->Reserved4));
> +	memset(smram->Reserved5, 0, sizeof(smram->Reserved5));
> +	memset(smram->Reserved6, 0, sizeof(smram->Reserved6));
> +	memset(smram->Reserved7, 0, sizeof(smram->Reserved7));
> +}
> -- 1.8.3.1