Messages in this thread Patch in this message | | | From | Lai Jiangshan <> | Subject | [RFC PATCH V2 1/7] x86/hw_breakpoint: add within_area() to check data breakpoints | Date | Tue, 26 May 2020 01:42:15 +0000 |
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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.
Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> --- arch/x86/kernel/hw_breakpoint.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c index 9ddf441ccaa8..c149c7b29ac3 100644 --- a/arch/x86/kernel/hw_breakpoint.c +++ b/arch/x86/kernel/hw_breakpoint.c @@ -227,14 +227,23 @@ int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw) return (va >= TASK_SIZE_MAX) || ((va + len - 1) >= TASK_SIZE_MAX); } +/* + * 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, -- 2.20.1
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