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centos-3.10-i686-fix-pcid-bug17925.patch 
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https://bugs.centos.org/view.php?id=17925
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When booting a recent 32-bit i686 kernel on a multi-cpu system with 'pcid' cpu feature, only the boot cpu is correctly initialized. The other cpu's fail to initialize, resulting in a badly running or crashing kernel.
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The reason is two missing patches present in vanilla upstream kernels:
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x86/mm: Disable PCID on 32-bit kernels
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x86/mm/32: Move setup_clear_cpu_cap(X86_FEATURE_PCID) earlier
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Submitted-by: Jerome Borsboom
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Applied-by: Akemi Yagi <toracat@centos.org>
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--- a/arch/x86/kernel/cpu/common.c	2020-10-21 10:17:08.000000000 -0700
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+++ b/arch/x86/kernel/cpu/common.c	2020-12-09 22:10:47.945329193 -0800
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@@ -1131,6 +1131,14 @@ static void __init early_identify_cpu(st
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 		this_cpu->c_bsp_init(c);
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 	cpu_set_bug_bits(c);
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+
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+#ifdef CONFIG_X86_32
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+	/*
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+	* Regardless of whether PCID is enumerated, the SDM says
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+	* that it can't be enabled in 32-bit mode.
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+	*/
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+	setup_clear_cpu_cap(X86_FEATURE_PCID);
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+#endif
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 }
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 void __init early_cpu_init(void)