4.16-stable review patch. If anyone has any objections, please let me know.
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From: Li RongQing lirongqing@baidu.com
commit a774635db5c430cbf21fa5d2f2df3d23aaa8e782 upstream.
The APIC ID as parsed from ACPI MADT is validity checked with the apic->apic_id_valid() callback, which depends on the selected APIC type.
For non X2APIC types APIC IDs >= 0xFF are invalid, but values > 0x7FFFFFFF are detected as valid. This happens because the 'apicid' argument of the apic_id_valid() callback is type 'int'. So the resulting comparison
apicid < 0xFF
evaluates to true for all unsigned int values > 0x7FFFFFFF which are handed to default_apic_id_valid(). As a consequence, invalid APIC IDs in !X2APIC mode are considered valid and accounted as possible CPUs.
Change the apicid argument type of the apic_id_valid() callback to u32 so the evaluation is unsigned and returns the correct result.
[ tglx: Massaged changelog ]
Signed-off-by: Li RongQing lirongqing@baidu.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Cc: stable@vger.kernel.org Cc: jgross@suse.com Cc: Dou Liyang douly.fnst@cn.fujitsu.com Cc: Peter Zijlstra peterz@infradead.org Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/1523322966-10296-1-git-send-email-lirongqing@baidu... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/include/asm/apic.h | 4 ++-- arch/x86/kernel/acpi/boot.c | 13 ++++++++----- 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, 16 insertions(+), 13 deletions(-)
--- a/arch/x86/include/asm/apic.h +++ b/arch/x86/include/asm/apic.h @@ -319,7 +319,7 @@ 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); @@ -492,7 +492,7 @@ static inline unsigned int read_apic_id( 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);
--- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -200,7 +200,7 @@ acpi_parse_x2apic(struct acpi_subtable_h { 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_h * 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) + pr_warn(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 --- 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(in 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); } --- 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(unsigne 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; --- 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); --- 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; } --- 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; } --- a/arch/x86/xen/apic.c +++ b/arch/x86/xen/apic.c @@ -112,7 +112,7 @@ static int xen_madt_oem_check(char *oem_ return xen_pv_domain(); }
-static int xen_id_always_valid(int apicid) +static int xen_id_always_valid(u32 apicid) { return 1; }