[4.19,12/17] ARM: split out processor lookup

Message ID	20190213213223.916-13-dave.long@linaro.org
State	Superseded
Headers	show Delivered-To: patches@linaro.org Received-SPF: pass (google.com: domain of dave.long@linaro.org designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; From: David Long <dave.long@linaro.org> To: stable@vger.kernel.org, Russell King - ARM Linux <linux@armlinux.org.uk>, Florian Fainelli <f.fainelli@gmail.com>, Julien Thierry <julien.thierry@arm.com>, Tony Lindgren <tony@atomide.com>, Marc Zyngier <marc.zyngier@arm.com>, Greg KH <gregkh@linuxfoundation.org>, Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com>, Mark Brown <broonie@kernel.org>, linux-kernel@vger.kernel.org Subject: [PATCH 4.19 12/17] ARM: split out processor lookup Date: Wed, 13 Feb 2019 16:32:18 -0500 Message-Id: <20190213213223.916-13-dave.long@linaro.org> In-Reply-To: <20190213213223.916-1-dave.long@linaro.org> References: <20190213213223.916-1-dave.long@linaro.org>
Series	V4.19 backport of more 32-bit arm spectre patches \| expand [4.19,00/17] V4.19 backport of more 32-bit arm spectre patches [4.19,01/17] ARM: 8789/1: signal: copy registers using __copy_to_user() [4.19,02/17] ARM: 8790/1: signal: always use __copy_to_user to save iwmmxt context [4.19,03/17] ARM: 8791/1: vfp: use __copy_to_user() when saving VFP state [4.19,04/17] ARM: 8792/1: oabi-compat: copy oabi events using __copy_to_user() [4.19,05/17] ARM: 8793/1: signal: replace __put_user_error with __put_user [4.19,06/17] ARM: 8794/1: uaccess: Prevent speculative use of the current addr_limit [4.19,07/17] ARM: 8795/1: spectre-v1.1: use put_user() for __put_user() [4.19,08/17] ARM: 8796/1: spectre-v1,v1.1: provide helpers for address sanitization [4.19,09/17] ARM: 8797/1: spectre-v1.1: harden __copy_to_user [4.19,10/17] ARM: 8810/1: vfp: Fix wrong assignement to ufp_exc [4.19,11/17] ARM: make lookup_processor_type() non-__init [4.19,12/17] ARM: split out processor lookup [4.19,13/17] ARM: clean up per-processor check_bugs method call [4.19,14/17] ARM: add PROC_VTABLE and PROC_TABLE macros [4.19,15/17] ARM: spectre-v2: per-CPU vtables to work around big.Little systems [4.19,16/17] ARM: ensure that processor vtables is not lost after boot [4.19,17/17] ARM: fix the cockup in the previous patch

Message ID

20190213213223.916-13-dave.long@linaro.org

State

Superseded

Headers

Received-SPF: pass (google.com: domain of dave.long@linaro.org designates
	209.85.220.65 as permitted sender) client-ip=209.85.220.65; 
From: David Long <dave.long@linaro.org>
To: stable@vger.kernel.org, Russell King - ARM Linux <linux@armlinux.org.uk>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Julien Thierry <julien.thierry@arm.com>,
	Tony Lindgren <tony@atomide.com>, Marc Zyngier <marc.zyngier@arm.com>,
	Greg KH <gregkh@linuxfoundation.org>, Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>, Mark Brown <broonie@kernel.org>,
	linux-kernel@vger.kernel.org
Subject: [PATCH 4.19 12/17] ARM: split out processor lookup
Date: Wed, 13 Feb 2019 16:32:18 -0500
Message-Id: <20190213213223.916-13-dave.long@linaro.org>
In-Reply-To: <20190213213223.916-1-dave.long@linaro.org>
References: <20190213213223.916-1-dave.long@linaro.org>

Series

V4.19 backport of more 32-bit arm spectre patches | expand

Commit Message

David Long Feb. 13, 2019, 9:32 p.m. UTC

From: Russell King <rmk+kernel@armlinux.org.uk>


Commit 65987a8553061515b5851b472081aedb9837a391 upstream.

Split out the lookup of the processor type and associated error handling
from the rest of setup_processor() - we will need to use this in the
secondary CPU bringup path for big.Little Spectre variant 2 mitigation.

Reviewed-by: Julien Thierry <julien.thierry@arm.com>

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Signed-off-by: David A. Long <dave.long@linaro.org>

---
 arch/arm/include/asm/cputype.h |  1 +
 arch/arm/kernel/setup.c        | 31 +++++++++++++++++++------------
 2 files changed, 20 insertions(+), 12 deletions(-)

-- 
2.17.1

diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
index 0d289240b6ca..775cac3c02bb 100644
--- a/arch/arm/include/asm/cputype.h
+++ b/arch/arm/include/asm/cputype.h
@@ -111,6 +111,7 @@ 
 #include <linux/kernel.h>
 
 extern unsigned int processor_id;
+struct proc_info_list *lookup_processor(u32 midr);
 
 #ifdef CONFIG_CPU_CP15
 #define read_cpuid(reg)							\
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 4c249cb261f3..8fd7baa158a4 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -667,22 +667,29 @@  static void __init smp_build_mpidr_hash(void)
 }
 #endif
 
-static void __init setup_processor(void)
+/*
+ * locate processor in the list of supported processor types.  The linker
+ * builds this table for us from the entries in arch/arm/mm/proc-*.S
+ */
+struct proc_info_list *lookup_processor(u32 midr)
 {
-	struct proc_info_list *list;
+	struct proc_info_list *list = lookup_processor_type(midr);
 
-	/*
-	 * locate processor in the list of supported processor
-	 * types.  The linker builds this table for us from the
-	 * entries in arch/arm/mm/proc-*.S
-	 */
-	list = lookup_processor_type(read_cpuid_id());
 	if (!list) {
-		pr_err("CPU configuration botched (ID %08x), unable to continue.\n",
-		       read_cpuid_id());
-		while (1);
+		pr_err("CPU%u: configuration botched (ID %08x), CPU halted\n",
+		       smp_processor_id(), midr);
+		while (1)
+		/* can't use cpu_relax() here as it may require MMU setup */;
 	}
 
+	return list;
+}
+
+static void __init setup_processor(void)
+{
+	unsigned int midr = read_cpuid_id();
+	struct proc_info_list *list = lookup_processor(midr);
+
 	cpu_name = list->cpu_name;
 	__cpu_architecture = __get_cpu_architecture();
 
@@ -700,7 +707,7 @@  static void __init setup_processor(void)
 #endif
 
 	pr_info("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n",
-		cpu_name, read_cpuid_id(), read_cpuid_id() & 15,
+		list->cpu_name, midr, midr & 15,
 		proc_arch[cpu_architecture()], get_cr());
 
 	snprintf(init_utsname()->machine, __NEW_UTS_LEN + 1, "%s%c",

[4.19,12/17] ARM: split out processor lookup

Commit Message

Patch