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Commit 0608d692 authored by Aneesh Kumar K.V's avatar Aneesh Kumar K.V Committed by Benjamin Herrenschmidt
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powerpc/mm: Always invalidate tlb on hpte invalidate and update 



If a hash bucket gets full, we "evict" a more/less random entry from it.
When we do that we don't invalidate the TLB (hpte_remove) because we assume
the old translation is still technically "valid". This implies that when
we are invalidating or updating pte, even if HPTE entry is not valid
we should do a tlb invalidate.

This was a regression introduced by b1022fbd

Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent 280a5ba2

arch/powerpc/mm/hash_native_64.c

+22 −8
Original line number Diff line number Diff line
@@ -336,11 +336,18 @@ static long native_hpte_updatepp(unsigned long slot, unsigned long newpp, 


	hpte_v = hptep->v;

	actual_psize = hpte_actual_psize(hptep, psize);

	/*

	 * We need to invalidate the TLB always because hpte_remove doesn't do

	 * a tlb invalidate. If a hash bucket gets full, we "evict" a more/less

	 * random entry from it. When we do that we don't invalidate the TLB

	 * (hpte_remove) because we assume the old translation is still

	 * technically "valid".

	 */

	if (actual_psize < 0) {

		native_unlock_hpte(hptep);

		return -1;

		actual_psize = psize;

		ret = -1;

		goto err_out;

	}

	/* Even if we miss, we need to invalidate the TLB */

	if (!HPTE_V_COMPARE(hpte_v, want_v)) {

		DBG_LOW(" -> miss\n");

		ret = -1;
@@ -350,6 +357,7 @@ static long native_hpte_updatepp(unsigned long slot, unsigned long newpp, 
		hptep->r = (hptep->r & ~(HPTE_R_PP | HPTE_R_N)) |

			(newpp & (HPTE_R_PP | HPTE_R_N | HPTE_R_C));

	}

err_out:

	native_unlock_hpte(hptep);



	/* Ensure it is out of the tlb too. */
@@ -409,7 +417,7 @@ static void native_hpte_updateboltedpp(unsigned long newpp, unsigned long ea, 
	hptep = htab_address + slot;

	actual_psize = hpte_actual_psize(hptep, psize);

	if (actual_psize < 0)

		return;

		actual_psize = psize;



	/* Update the HPTE */

	hptep->r = (hptep->r & ~(HPTE_R_PP | HPTE_R_N)) |
@@ -437,21 +445,27 @@ static void native_hpte_invalidate(unsigned long slot, unsigned long vpn, 
	hpte_v = hptep->v;



	actual_psize = hpte_actual_psize(hptep, psize);

	/*

	 * We need to invalidate the TLB always because hpte_remove doesn't do

	 * a tlb invalidate. If a hash bucket gets full, we "evict" a more/less

	 * random entry from it. When we do that we don't invalidate the TLB

	 * (hpte_remove) because we assume the old translation is still

	 * technically "valid".

	 */

	if (actual_psize < 0) {

		actual_psize = psize;

		native_unlock_hpte(hptep);

		local_irq_restore(flags);

		return;

		goto err_out;

	}

	/* Even if we miss, we need to invalidate the TLB */

	if (!HPTE_V_COMPARE(hpte_v, want_v))

		native_unlock_hpte(hptep);

	else

		/* Invalidate the hpte. NOTE: this also unlocks it */

		hptep->v = 0;



err_out:

	/* Invalidate the TLB */

	tlbie(vpn, psize, actual_psize, ssize, local);



	local_irq_restore(flags);

}