Messages in this thread Patch in this message | | | From | Geert Uytterhoeven <> | Subject | [PATCH 1/3] RISC-V: Fix hartid mask handling for hartid 31 and up | Date | Mon, 31 Jan 2022 14:26:20 +0100 |
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Jessica reports that using "1 << hartid" causes undefined behavior for hartid 31 and up.
Fix this by using the BIT() helper instead of an explicit shift.
Reported-by: Jessica Clarke <jrtc27@jrtc27.com> Fixes: 26fb751ca37846c9 ("RISC-V: Do not use cpumask data structure for hartid bitmap") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> --- arch/riscv/kernel/sbi.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c index f72527fcb34709a6..f93bc75f2bc43c8e 100644 --- a/arch/riscv/kernel/sbi.c +++ b/arch/riscv/kernel/sbi.c @@ -5,6 +5,7 @@ * Copyright (c) 2020 Western Digital Corporation or its affiliates. */ +#include <linux/bits.h> #include <linux/init.h> #include <linux/pm.h> #include <linux/reboot.h> @@ -85,7 +86,7 @@ static unsigned long __sbi_v01_cpumask_to_hartmask(const struct cpumask *cpu_mas pr_warn("Unable to send any request to hartid > BITS_PER_LONG for SBI v0.1\n"); break; } - hmask |= 1 << hartid; + hmask |= BIT(hartid); } return hmask; @@ -268,7 +269,7 @@ static int __sbi_send_ipi_v02(const struct cpumask *cpu_mask) } if (!hmask) hbase = hartid; - hmask |= 1UL << (hartid - hbase); + hmask |= BIT(hartid - hbase); } if (hmask) { @@ -362,7 +363,7 @@ static int __sbi_rfence_v02(int fid, const struct cpumask *cpu_mask, } if (!hmask) hbase = hartid; - hmask |= 1UL << (hartid - hbase); + hmask |= BIT(hartid - hbase); } if (hmask) { -- 2.25.1
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