x86/platform: Control warm reset setup via legacy feature flag

Allow to turn off the setup of BIOS-managed warm reset via a new flag in
x86_legacy_features. Besides the UV1, the upcoming jailhose guest support
needs this switched off.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: jailhouse-dev@googlegroups.com
Link: https://lkml.kernel.org/r/44376558129d70a2c1527959811371ef4b82e829.1511770314.git.jan.kiszka@siemens.com

diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index aa4747569e23b63ea9cb83912bb6960caa8525cc..fc2f082ac635a1cc08ec2dbf0fe5d5cd6ee28edd 100644 (file)
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -212,6 +212,7 @@ enum x86_legacy_i8042_state {
 struct x86_legacy_features {
        enum x86_legacy_i8042_state i8042;
        int rtc;
+       int warm_reset;
        int no_vga;
        int reserve_bios_regions;
        struct x86_legacy_devices devices;

diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index e1b8e8bf6b3c2572b30f0de39957c602abc2434d..6de35fc8fb3a995e5f81a9d3320df010e3f1ebbd 100644 (file)
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -316,6 +316,7 @@ static int __init uv_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
        } else if (!strcmp(oem_table_id, "UVH")) {
                /* Only UV1 systems: */
                uv_system_type = UV_NON_UNIQUE_APIC;
+               x86_platform.legacy.warm_reset = 0;
                __this_cpu_write(x2apic_extra_bits, pnodeid << uvh_apicid.s.pnode_shift);
                uv_set_apicid_hibit();
                uv_apic = 1;

diff --git a/arch/x86/kernel/platform-quirks.c b/arch/x86/kernel/platform-quirks.c
index 39a59299bfa08ec4884065c75cd5b61cc275e72b..235fe6008ac889ae9867d916c9461ddaefaa11dd 100644 (file)
--- a/arch/x86/kernel/platform-quirks.c
+++ b/arch/x86/kernel/platform-quirks.c
@@ -9,6 +9,7 @@ void __init x86_early_init_platform_quirks(void)
 {
        x86_platform.legacy.i8042 = X86_LEGACY_I8042_EXPECTED_PRESENT;
        x86_platform.legacy.rtc = 1;
+       x86_platform.legacy.warm_reset = 1;
        x86_platform.legacy.reserve_bios_regions = 0;
        x86_platform.legacy.devices.pnpbios = 1;
 

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index ed556d50d7ed6d71f03d202ef84a6b6b54e95a02..9adcae1b135c9b6f915423de3f2ba8314808003e 100644 (file)
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -934,7 +934,7 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle,
         * the targeted processor.
         */
 
-       if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
+       if (x86_platform.legacy.warm_reset) {
 
                pr_debug("Setting warm reset code and vector.\n");
 
@@ -1006,7 +1006,7 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle,
        /* mark "stuck" area as not stuck */
        *trampoline_status = 0;
 
-       if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
+       if (x86_platform.legacy.warm_reset) {
                /*
                 * Cleanup possible dangling ends...
                 */