From 79d7517b899ef695bf0674afb4e5ce1b1a4ecfeb Mon Sep 17 00:00:00 2001 From: David Daney Date: Tue, 26 Feb 2013 14:35:23 -0800 Subject: [PATCH] MIPS: Fix logic errors in bitops.c commit 0c81157b46c533139d6be721d41617020c59a2c3 upstream. commit 92d11594f6 (MIPS: Remove irqflags.h dependency from bitops.h) factored some of the bitops code out into a separate file (arch/mips/lib/bitops.c). Unfortunately the logic converting a bit mask into a boolean result was lost in some of the functions. We had: int res; unsigned long shifted_result_bit; . . . res = shifted_result_bit; return res; Which truncates off the high 32 bits (thus yielding an incorrect value) on 64-bit systems. The manifestation of this is that a non-SMP 64-bit kernel will not boot as the bitmap operations in bootmem.c are all screwed up. Signed-off-by: David Daney Cc: linux-mips@linux-mips.org Cc: Jim Quinlan Patchwork: https://patchwork.linux-mips.org/patch/4965/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman --- arch/mips/lib/bitops.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/mips/lib/bitops.c b/arch/mips/lib/bitops.c index 239a9c957b02..f3f7756497e2 100644 --- a/arch/mips/lib/bitops.c +++ b/arch/mips/lib/bitops.c @@ -90,12 +90,12 @@ int __mips_test_and_set_bit(unsigned long nr, unsigned bit = nr & SZLONG_MASK; unsigned long mask; unsigned long flags; - unsigned long res; + int res; a += nr >> SZLONG_LOG; mask = 1UL << bit; raw_local_irq_save(flags); - res = (mask & *a); + res = (mask & *a) != 0; *a |= mask; raw_local_irq_restore(flags); return res; @@ -116,12 +116,12 @@ int __mips_test_and_set_bit_lock(unsigned long nr, unsigned bit = nr & SZLONG_MASK; unsigned long mask; unsigned long flags; - unsigned long res; + int res; a += nr >> SZLONG_LOG; mask = 1UL << bit; raw_local_irq_save(flags); - res = (mask & *a); + res = (mask & *a) != 0; *a |= mask; raw_local_irq_restore(flags); return res; @@ -141,12 +141,12 @@ int __mips_test_and_clear_bit(unsigned long nr, volatile unsigned long *addr) unsigned bit = nr & SZLONG_MASK; unsigned long mask; unsigned long flags; - unsigned long res; + int res; a += nr >> SZLONG_LOG; mask = 1UL << bit; raw_local_irq_save(flags); - res = (mask & *a); + res = (mask & *a) != 0; *a &= ~mask; raw_local_irq_restore(flags); return res; @@ -166,12 +166,12 @@ int __mips_test_and_change_bit(unsigned long nr, volatile unsigned long *addr) unsigned bit = nr & SZLONG_MASK; unsigned long mask; unsigned long flags; - unsigned long res; + int res; a += nr >> SZLONG_LOG; mask = 1UL << bit; raw_local_irq_save(flags); - res = (mask & *a); + res = (mask & *a) != 0; *a ^= mask; raw_local_irq_restore(flags); return res; -- 2.39.5