Re: çå: çå: [RFC PATCH] x86/acpi: Prevent x2apic id -1 from being accounted

From: Dou Liyang
Date: Mon Apr 09 2018 - 08:16:22 EST


Hi Rongqing,

At 04/09/2018 05:33 PM, Li,Rongqing wrote:
[...]
Thanks. How about the below modification:


It is good to me. you need start a new v2 thread for this. so
that maintainers can easy to get it.

commit 96ba42cf87ce0e62d500004c01bfa9a9479b2e87
Author: Li RongQing <lirongqing@xxxxxxxxx>
Date: Sun Apr 8 18:54:10 2018 +0800

x86/acpi: Prevent all the X2APIC Id from being parsed in non-x2apic mode
the values of x2APIC ID is greater than 0xff in ACPI MADT, if acpi
is apic_flat, default_apic_id_valid() is called to check id which
is converted from u32 to int, will return true if id is larger than
0x7fffffff, this is wrong
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@xxxxxxxxx>
Suggested-by:: Dou Liyang <douly.fnst@xxxxxxxxxxxxxx>
  Â^-----------^---- no need to add this, it is my pleasure


Thanks,

dou

Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

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..4ba949de1ca9 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 +222,13 @@ 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)
- printk(KERN_WARNING PREFIX "x2apic entry ignored\n");
- else
- acpi_register_lapic(apic_id, processor->uid, enabled);
+ if (!apic->apic_id_valid(apic_id)) {
+ if (enabled)
+ printk(KERN_WARNING PREFIX "x2apic entry ignored\n");
+ return 0;
+ }
+
+ acpi_register_lapic(apic_id, processor->uid, enabled);
#else
printk(KERN_WARNING PREFIX "x2apic entry ignored\n");
#endif
diff --git a/arch/x86/kernel/apic/apic_common.c b/arch/x86/kernel/apic/apic_common.c
index a360801779ae..02b4839478b1 100644
--- a/arch/x86/kernel/apic/apic_common.c
+++ b/arch/x86/kernel/apic/apic_common.c
@@ -40,7 +40,7 @@ int default_check_phys_apicid_present(int phys_apicid)
return physid_isset(phys_apicid, phys_cpu_present_map);
}
-int default_apic_id_valid(int apicid)
+int default_apic_id_valid(u32 apicid)
{
return (apicid < 255);
}
diff --git a/arch/x86/kernel/apic/apic_numachip.c b/arch/x86/kernel/apic/apic_numachip.c
index 134e04506ab4..78778b54f904 100644
--- a/arch/x86/kernel/apic/apic_numachip.c
+++ b/arch/x86/kernel/apic/apic_numachip.c
@@ -56,7 +56,7 @@ static u32 numachip2_set_apic_id(unsigned int id)
return id << 24;
}
-static int numachip_apic_id_valid(int apicid)
+static int numachip_apic_id_valid(u32 apicid)
{
/* Trust what bootloader passes in MADT */
return 1;
diff --git a/arch/x86/kernel/apic/x2apic.h b/arch/x86/kernel/apic/x2apic.h
index b107de381cb5..a49b3604027f 100644
--- a/arch/x86/kernel/apic/x2apic.h
+++ b/arch/x86/kernel/apic/x2apic.h
@@ -1,6 +1,6 @@
/* Common bits for X2APIC cluster/physical modes. */
-int x2apic_apic_id_valid(int apicid);
+int x2apic_apic_id_valid(u32 apicid);
int x2apic_apic_id_registered(void);
void __x2apic_send_IPI_dest(unsigned int apicid, int vector, unsigned int dest);
unsigned int x2apic_get_apic_id(unsigned long id);
diff --git a/arch/x86/kernel/apic/x2apic_phys.c b/arch/x86/kernel/apic/x2apic_phys.c
index e2829bf40e4a..b5cf9e7b3830 100644
--- a/arch/x86/kernel/apic/x2apic_phys.c
+++ b/arch/x86/kernel/apic/x2apic_phys.c
@@ -101,7 +101,7 @@ static int x2apic_phys_probe(void)
}
/* Common x2apic functions, also used by x2apic_cluster */
-int x2apic_apic_id_valid(int apicid)
+int x2apic_apic_id_valid(u32 apicid)
{
return 1;
}
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index f11910b44638..efaf2d4f9c3c 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -557,7 +557,7 @@ static void uv_send_IPI_all(int vector)
uv_send_IPI_mask(cpu_online_mask, vector);
}
-static int uv_apic_id_valid(int apicid)
+static int uv_apic_id_valid(u32 apicid)
{
return 1;
}
diff --git a/arch/x86/xen/apic.c b/arch/x86/xen/apic.c
index 2163888497d3..5e53bfbe5823 100644
--- a/arch/x86/xen/apic.c
+++ b/arch/x86/xen/apic.c
@@ -112,7 +112,7 @@ static int xen_madt_oem_check(char *oem_id, char *oem_table_id)
return xen_pv_domain();
}
-static int xen_id_always_valid(int apicid)
+static int xen_id_always_valid(u32 apicid)
{
return 1;
}