On Mon, Dec 19, 2016 at 03:18:07PM +0530, Aneesh Kumar K.V wrote:
Reza Arbab <ar...@linux.vnet.ibm.com> writes:+static void remove_pte_table(pte_t *pte_start, unsigned long addr, + unsigned long end) +{ + unsigned long next; + pte_t *pte; + + pte = pte_start + pte_index(addr); + for (; addr < end; addr = next, pte++) { + next = (addr + PAGE_SIZE) & PAGE_MASK; + if (next > end) + next = end; + + if (!pte_present(*pte)) + continue; + + spin_lock(&init_mm.page_table_lock); + pte_clear(&init_mm, addr, pte); + spin_unlock(&init_mm.page_table_lock); + } + + flush_tlb_mm(&init_mm);Why call a flush here. we do that at the end of remove_page_table . Isn't that sufficient ?
This was carried over from the x86 version of the function, where they do flush_tlb_all(). I can experiment to make sure things work without it.
+static void remove_pagetable(unsigned long start, unsigned long end, + unsigned long map_page_size) +{ + unsigned long next; + unsigned long addr; + pgd_t *pgd; + pud_t *pud; + + for (addr = start; addr < end; addr = next) { + next = pgd_addr_end(addr, end); + + pgd = pgd_offset_k(addr); + if (!pgd_present(*pgd)) + continue; + + pud = (pud_t *)pgd_page_vaddr(*pgd); + remove_pud_table(pud, addr, next, map_page_size); + free_pud_table(pud, pgd); + } + + flush_tlb_mm(&init_mm);So we want to flush the full kernel tlb when we do a hotplug ? May be check using flush_tlb_kernel_range(). Also that flush_tlb_mm() do check for mm_is_thread_local(). Do we update init_mm correct to handle that check ? I assume we want a tlbie() here instead of tlbiel() ?
I'll try using flush_tlb_kernel_range() instead. That sure does seem more appropriate.
-- Reza Arbab
