Unverified Commit 12f4a665 authored by Geert Uytterhoeven's avatar Geert Uytterhoeven Committed by Palmer Dabbelt
Browse files

RISC-V: Fix hartid mask handling for hartid 31 and up 



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: default avatarJessica Clarke <jrtc27@jrtc27.com>
Fixes: 26fb751c ("RISC-V: Do not use cpumask data structure for hartid bitmap")
Signed-off-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: default avatarAtish Patra <atishp@rivosinc.com>
Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent 6df2a016

arch/riscv/kernel/sbi.c

+4 −3
Original line number Diff line number Diff line
@@ -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) {