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charset=us-ascii Content-Disposition: inline In-Reply-To: <20241015-arm-kasan-vmalloc-crash-v1-1-dbb23592ca83@linaro.org> Sender: Russell King (Oracle) On Tue, Oct 15, 2024 at 11:37:14PM +0200, Linus Walleij wrote: > @@ -125,6 +126,12 @@ void __check_vmalloc_seq(struct mm_struct *mm) > pgd_offset_k(VMALLOC_START), > sizeof(pgd_t) * (pgd_index(VMALLOC_END) - > pgd_index(VMALLOC_START))); > + if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) { > + memcpy(pgd_offset(mm, (unsigned long)kasan_mem_to_shadow((void *)VMALLOC_START)), > + pgd_offset_k((unsigned long)kasan_mem_to_shadow((void *)VMALLOC_START)), > + sizeof(pgd_t) * (pgd_index((unsigned long)kasan_mem_to_shadow((void *)VMALLOC_END)) - > + pgd_index((unsigned long)kasan_mem_to_shadow((void *)VMALLOC_START)))); Maybe the following would be more readable: static unsigned long arm_kasan_mem_to_shadow(unsigned long addr) { return (unsigned long)kasan_mem_to_shadow((void *)addr); } static void memcpy_pgd(struct mm_struct *mm, unsigned long start, unsigned long end) { memcpy(pgd_offset(mm, start), pgd_offset_k(start), sizeof(pgd_t) * (pgd_index(end) - pgd_index(start))); } seq = ...; memcpy_pgd(mm, VMALLOC_START, VMALLOC_END); if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) { unsigned long start = arm_kasan_mem_to_shadow(VMALLOC_START); unsigned long end = arm_kasan_mem_to_shadow(VMALLOC_END); memcpy_pgd(mm, start, end); > + } ? -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!