From b7abc5c53e3c65b8e931bd96db2d08ba670e111a Mon Sep 17 00:00:00 2001 From: "Sachin P. Sant" Date: Thu, 14 Jun 2007 15:31:34 +1000 Subject: [POWERPC] Fix Kexec/Kdump for power6 On Power machines supporting VRMA, Kexec/Kdump does not work. VRMA (virtual real-mode area) means that accesses with IR/DR = 0 (i.e. the MMU "off") actually still go through the hash table, using entries put there by the hypervisor. This means that when we clear out the hash table on kexec, we need to make sure these entries are left untouched. This also adds plpar_pte_read_raw() on the lines of plpar_pte_remove_raw(). Signed-off-by : Sachin Sant Signed-off-by : Mohan Kumar M Acked-by: Benjamin Herrenschmidt Acked-by: Olof Johansson Signed-off-by: Paul Mackerras --- arch/powerpc/platforms/pseries/lpar.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) (limited to 'arch/powerpc/platforms/pseries/lpar.c') diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c index 362dfbc260a..8cc6eeeaae2 100644 --- a/arch/powerpc/platforms/pseries/lpar.c +++ b/arch/powerpc/platforms/pseries/lpar.c @@ -373,12 +373,23 @@ static void pSeries_lpar_hptab_clear(void) { unsigned long size_bytes = 1UL << ppc64_pft_size; unsigned long hpte_count = size_bytes >> 4; - unsigned long dummy1, dummy2; + unsigned long dummy1, dummy2, dword0; + long lpar_rc; int i; /* TODO: Use bulk call */ - for (i = 0; i < hpte_count; i++) - plpar_pte_remove_raw(0, i, 0, &dummy1, &dummy2); + for (i = 0; i < hpte_count; i++) { + /* dont remove HPTEs with VRMA mappings */ + lpar_rc = plpar_pte_remove_raw(H_ANDCOND, i, HPTE_V_1TB_SEG, + &dummy1, &dummy2); + if (lpar_rc == H_NOT_FOUND) { + lpar_rc = plpar_pte_read_raw(0, i, &dword0, &dummy1); + if (!lpar_rc && ((dword0 & HPTE_V_VRMA_MASK) + != HPTE_V_VRMA_MASK)) + /* Can be hpte for 1TB Seg. So remove it */ + plpar_pte_remove_raw(0, i, 0, &dummy1, &dummy2); + } + } } /* -- cgit v1.2.3