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From:   David Brazdil <dbrazdil@google.com>
To:     kvmarm@lists.cs.columbia.edu
Cc:     Jonathan Corbet <corbet@lwn.net>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>, Marc Zyngier <maz@kernel.org>,
        James Morse <james.morse@arm.com>,
        Julien Thierry <julien.thierry.kdev@gmail.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Dennis Zhou <dennis@kernel.org>, Tejun Heo <tj@kernel.org>,
        Christoph Lameter <cl@linux.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Sudeep Holla <sudeep.holla@arm.com>, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        kernel-team@android.com, David Brazdil <dbrazdil@google.com>
Subject: [PATCH v4 07/26] arm64: Make cpu_logical_map() take unsigned int
Date:   Wed,  2 Dec 2020 18:41:03 +0000
Message-Id: <20201202184122.26046-8-dbrazdil@google.com>
In-Reply-To: <20201202184122.26046-1-dbrazdil@google.com>
References: <20201202184122.26046-1-dbrazdil@google.com>
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CPU index should never be negative. Change the signature of
(set_)cpu_logical_map to take an unsigned int.

This still works even if the users treat the CPU index as an int,
and will allow the hypervisor's implementation to check that the index
is valid with a single upper-bound check.

Signed-off-by: David Brazdil <dbrazdil@google.com>
---
 arch/arm64/include/asm/smp.h | 4 ++--
 arch/arm64/kernel/setup.c    | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h
index 2e7f529ec5a6..bcb01ca15325 100644
--- a/arch/arm64/include/asm/smp.h
+++ b/arch/arm64/include/asm/smp.h
@@ -46,9 +46,9 @@ DECLARE_PER_CPU_READ_MOSTLY(int, cpu_number);
  * Logical CPU mapping.
  */
 extern u64 __cpu_logical_map[NR_CPUS];
-extern u64 cpu_logical_map(int cpu);
+extern u64 cpu_logical_map(unsigned int cpu);
 
-static inline void set_cpu_logical_map(int cpu, u64 hwid)
+static inline void set_cpu_logical_map(unsigned int cpu, u64 hwid)
 {
 	__cpu_logical_map[cpu] = hwid;
 }
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 133257ffd859..2f2973bc67c7 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -276,7 +276,7 @@ arch_initcall(reserve_memblock_reserved_regions);
 
 u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID };
 
-u64 cpu_logical_map(int cpu)
+u64 cpu_logical_map(unsigned int cpu)
 {
 	return __cpu_logical_map[cpu];
 }
-- 
2.29.2.454.gaff20da3a2-goog