Messages in this thread Patch in this message |  | | Subject | Re: 答复: [RFC PATCH] x86/acpi: Prevent x2a pic id -1 from being accounted | From | Dou Liyang <> | Date | Mon, 9 Apr 2018 16:46:55 +0800 |
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RongQing,
At 04/09/2018 02:38 PM, Li,Rongqing wrote: > > >> -----邮件原件----- >> 发件人: Dou Liyang [mailto:douly.fnst@cn.fujitsu.com] >> 发送时间: 2018年4月9日 13:38 >> 收件人: Li,Rongqing <lirongqing@baidu.com>; linux-kernel@vger.kernel.org; >> tglx@linutronix.de; mingo@redhat.com; hpa@zytor.com; jgross@suse.com; >> x86@kernel.org; peterz@infradead.org >> 主题: Re: [RFC PATCH] x86/acpi: Prevent x2apic id -1 from being accounted >> >> Hi RongQing, >> >> Is there an local x2apic whose ID is in your machine? >> > > I think no
[...]
> [ 0.000000] ACPI: X2APIC (apic_id[0xffffffff] uid[0x00] disabled) > [ 0.000000] ACPI: X2APIC (apic_id[0xffffffff] uid[0x01] disabled) > [ 0.000000] ACPI: X2APIC (apic_id[0xffffffff] uid[0x02] disabled)
Ah, sure enough!
[...] > > >> At 04/08/2018 07:38 PM, Li RongQing wrote: >>> local_apic_id of acpi_madt_local_x2apic is u32, it is converted to int >>> when checked by default_apic_id_valid() and return true if it is >>> larger than 0x7fffffff, this is wrong >>> >> >> For x2apic enabled systems, >> >> - the byte length of X2APIC ID is 4, and it can be larger than >> 0x7fffffff in theory >> > > Yes > >> - the ->apic_id_valid points to x2apic_apic_id_valid(), which always >> return _ture_ , not default_apic_id_valid(). >> > > To this machine, the apic is apic_flat
I see, I am sorry the title and changelog make me misunderstand.
Here, actually, we prevent all the X2APIC Id from being parsed in non-x2apic mode, not just 0xFFFFFFFF. because the values of x2APIC ID must be 255 and greater in ACPI MADT.
> > -RongQing > >> Thanks, >> dou >> >>> and if local_apic_id is invalid, we should prevent it from being >>> accounted > This fixes a bug that Purley platform displays too many >>> possible cpu >>> >>> Signed-off-by: Li RongQing <lirongqing@baidu.com> >>> Cc: Peter Zijlstra <peterz@infradead.org> >>> Cc: Thomas Gleixner <tglx@linutronix.de> >>> Cc: Dou Liyang <douly.fnst@cn.fujitsu.com> >>> --- >>> arch/x86/include/asm/apic.h | 4 ++-- >>> arch/x86/kernel/acpi/boot.c | 10 ++++++---- >>> arch/x86/kernel/apic/apic_common.c | 2 +- >>> arch/x86/kernel/apic/apic_numachip.c | 2 +- >>> arch/x86/kernel/apic/x2apic.h | 2 +- >>> arch/x86/kernel/apic/x2apic_phys.c | 2 +- >>> arch/x86/kernel/apic/x2apic_uv_x.c | 2 +- >>> arch/x86/xen/apic.c | 2 +- >>> 8 files changed, 14 insertions(+), 12 deletions(-) >>> >>> diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h >>> index 40a3d3642f3a..08acd954f00e 100644 >>> --- a/arch/x86/include/asm/apic.h >>> +++ b/arch/x86/include/asm/apic.h >>> @@ -313,7 +313,7 @@ struct apic { >>> /* Probe, setup and smpboot functions */ >>> int (*probe)(void); >>> int (*acpi_madt_oem_check)(char *oem_id, char >> *oem_table_id); >>> - int (*apic_id_valid)(int apicid); >>> + int (*apic_id_valid)(u32 apicid); >>> int (*apic_id_registered)(void); >>> >>> bool (*check_apicid_used)(physid_mask_t *map, int apicid); >>> @@ -486,7 +486,7 @@ static inline unsigned int read_apic_id(void) >>> return apic->get_apic_id(reg); >>> } >>> >>> -extern int default_apic_id_valid(int apicid); >>> +extern int default_apic_id_valid(u32 apicid); >>> extern int default_acpi_madt_oem_check(char *, char *); >>> extern void default_setup_apic_routing(void); >>> >>> diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c >>> index 7a37d9357bc4..7412564dc2a7 100644 >>> --- a/arch/x86/kernel/acpi/boot.c >>> +++ b/arch/x86/kernel/acpi/boot.c >>> @@ -200,7 +200,7 @@ acpi_parse_x2apic(struct acpi_subtable_header >> *header, const unsigned long end) >>> { >>> struct acpi_madt_local_x2apic *processor = NULL; >>> #ifdef CONFIG_X86_X2APIC >>> - int apic_id; >>> + u32 apic_id; >>> u8 enabled; >>> #endif >>> >>> @@ -222,10 +222,12 @@ acpi_parse_x2apic(struct acpi_subtable_header >> *header, const unsigned long end) >>> * to not preallocating memory for all NR_CPUS >>> * when we use CPU hotplug. >>> */ >>> - if (!apic->apic_id_valid(apic_id) && enabled) >>> + if (!apic->apic_id_valid(apic_id)) { >>> printk(KERN_WARNING PREFIX "x2apic entry ignored\n");
Due to the disable APIC entries may not exist physically, please just printk the warning if the APIC ID is enabled.
if (!apic->apic_id_valid(apic_id)) { if(enabled) printk...
return 0; }
Thanks, dou
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