From: Lai Jiangshan <la...@linux.alibaba.com> within_area() is added for checking if the data breakpoints overlap with cpu_entry_area, and will be used for checking if the data breakpoints overlap with GDT, IDT, or TSS in places other than cpu_entry_area next patches.
Signed-off-by: Lai Jiangshan <la...@linux.alibaba.com> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Link: https://lkml.kernel.org/r/20200526014221.2119-2-la...@linux.alibaba.com --- arch/x86/kernel/hw_breakpoint.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) --- a/arch/x86/kernel/hw_breakpoint.c +++ b/arch/x86/kernel/hw_breakpoint.c @@ -228,13 +228,22 @@ int arch_check_bp_in_kernelspace(struct } /* + * Checks whether the range [addr, end], overlaps the area [base, base + size). + */ +static inline bool within_area(unsigned long addr, unsigned long end, + unsigned long base, unsigned long size) +{ + return end >= base && addr < (base + size); +} + +/* * Checks whether the range from addr to end, inclusive, overlaps the CPU * entry area range. */ static inline bool within_cpu_entry_area(unsigned long addr, unsigned long end) { - return end >= CPU_ENTRY_AREA_BASE && - addr < (CPU_ENTRY_AREA_BASE + CPU_ENTRY_AREA_TOTAL_SIZE); + return within_area(addr, end, CPU_ENTRY_AREA_BASE, + CPU_ENTRY_AREA_TOTAL_SIZE); } static int arch_build_bp_info(struct perf_event *bp,
