On 3/26/2018 3:25 PM, Mark Rutland wrote:
On Tue, Mar 20, 2018 at 05:15:13PM +0530, Chintan Pandya wrote:
+static int __pmd_free_pte_page(pmd_t *pmd, unsigned long addr, bool tlb_inv)
+{
+ pmd_t *table;
+
+ if (pmd_val(*pmd)) {
+ table = __va(pmd_val(*pmd));
+ pmd_clear(pmd);
+ /*
+ * FIXME: __flush_tlb_pgtable(&init_mm, addr) is
+ * ideal candidate here, which exactly
+ * flushes intermediate pgtables. But,
+ * this is broken (evident from tests).
+ * So, use safe TLB op unless that is fixed.
+ */
+ if (tlb_inv)
+ flush_tlb_kernel_range(addr, addr + PMD_SIZE);
I don't think that __flush_tlb_pgtable() is broken. It's only valid to
call it for user page tables, since it doesn't affect all ASIDs.
We can add a simlar helper for kernel mappings, which affects all ASIDs,
e.g.
Okay. I will test it and update v5.
static inline void __flush_tlb_kernel_pgtable(unsigned long addr)
{
addr >>= 12;
__tlbi(vaae1is, addr);
dsb(ish);
}
Thanks,
Mark.
Chintan
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