From: Saurabh Sengar <ssengar@linux.microsoft.com>
To: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org,
decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com,
bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org,
mikelley@microsoft.com, linux-kernel@vger.kernel.org,
linux-hyperv@vger.kernel.org, hpa@zytor.com
Subject: [PATCH] x86/hyperv: add noop functions to x86_init mpparse functions
Date: Fri, 2 Jun 2023 05:41:52 -0700 [thread overview]
Message-ID: <1685709712-13752-1-git-send-email-ssengar@linux.microsoft.com> (raw)
In !ACPI system, there is no way to disable CONFIG_X86_MPPARSE.
When CONFIG_X86_MPPARSE is enabled for VTL2, the kernel will
scan low memory looking for MP tables. Don't allow this, because
low memory is controlled by VTL0 and may contain actual valid
tables for VTL0, which can confuse the VTL2 kernel.
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
---
arch/x86/hyperv/hv_vtl.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/x86/hyperv/hv_vtl.c b/arch/x86/hyperv/hv_vtl.c
index 1ba5d3b99b16..ea21d897b5da 100644
--- a/arch/x86/hyperv/hv_vtl.c
+++ b/arch/x86/hyperv/hv_vtl.c
@@ -23,6 +23,10 @@ void __init hv_vtl_init_platform(void)
x86_init.irqs.pre_vector_init = x86_init_noop;
x86_init.timers.timer_init = x86_init_noop;
+ /* Avoid searching for BIOS MP tables */
+ x86_init.mpparse.find_smp_config = x86_init_noop;
+ x86_init.mpparse.get_smp_config = x86_init_uint_noop;
+
x86_platform.get_wallclock = get_rtc_noop;
x86_platform.set_wallclock = set_rtc_noop;
x86_platform.get_nmi_reason = hv_get_nmi_reason;
--
2.34.1
next reply other threads:[~2023-06-02 12:41 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-02 12:41 Saurabh Sengar [this message]
2023-06-02 15:33 ` [PATCH] x86/hyperv: add noop functions to x86_init mpparse functions Dave Hansen
2023-06-02 16:17 ` Wei Liu
2023-06-02 16:21 ` Dave Hansen
2023-06-02 16:22 ` Wei Liu
2023-06-02 16:27 ` [EXTERNAL] " Saurabh Singh Sengar
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