Re: [Patch ] Kexec Kdump support for POWER6
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2007-05-30 11:43:17
On Wed, 2007-05-30 at 10:50 +0530, Sachin P. Sant wrote:
Paul, here is the final version of the patch with all review comments incorporated. Thanks -Sachin plain text document attachment (kexec-kdump-support-on-POWER6) * On Power machines supporting VRMA, Kexec/Kdump does not work. * Hypervisor stores VRMA mapping used by the OS, in the hpte hash tables. * Make sure these hpte entries are left untouched. * * This patch also adds plpar_pte_read_raw() on the lines of * plpar_pte_remove_raw(). Signed-off-by : Sachin Sant [off-list ref] Signed-off-by : Mohan Kumar M [off-list ref]
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
quoted hunk ↗ jump to hunk
diff -Naurp a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c--- a/arch/powerpc/platforms/pseries/lpar.c 2007-05-19 09:36:17.000000000 +0530 +++ b/arch/powerpc/platforms/pseries/lpar.c 2007-05-29 10:45:34.000000000 +0530@@ -373,12 +373,23 @@ static void pSeries_lpar_hptab_clear(voi { 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); + } + } } /*diff -Naurp a/arch/powerpc/platforms/pseries/plpar_wrappers.h b/arch/powerpc/platforms/pseries/plpar_wrappers.h--- a/arch/powerpc/platforms/pseries/plpar_wrappers.h 2007-05-19 09:36:17.000000000 +0530 +++ b/arch/powerpc/platforms/pseries/plpar_wrappers.h 2007-05-25 12:20:38.000000000 +0530@@ -108,6 +108,21 @@ static inline long plpar_pte_read(unsign return rc; } +/* plpar_pte_read_raw can be called in real mode. It calls plpar_hcall_raw */ +static inline long plpar_pte_read_raw(unsigned long flags, unsigned long ptex, + unsigned long *old_pteh_ret, unsigned long *old_ptel_ret) +{ + long rc; + unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; + + rc = plpar_hcall_raw(H_READ, retbuf, flags, ptex); + + *old_pteh_ret = retbuf[0]; + *old_ptel_ret = retbuf[1]; + + return rc; +} + static inline long plpar_pte_protect(unsigned long flags, unsigned long ptex, unsigned long avpn) {diff -Naurp a/include/asm-powerpc/mmu-hash64.h b/include/asm-powerpc/mmu-hash64.h--- a/include/asm-powerpc/mmu-hash64.h 2007-05-19 09:36:17.000000000 +0530 +++ b/include/asm-powerpc/mmu-hash64.h 2007-05-29 10:46:22.000000000 +0530@@ -94,6 +94,9 @@ extern char initial_stab[]; #define HPTE_R_C ASM_CONST(0x0000000000000080) #define HPTE_R_R ASM_CONST(0x0000000000000100) +#define HPTE_V_1TB_SEG ASM_CONST(0x4000000000000000) +#define HPTE_V_VRMA_MASK ASM_CONST(0x4001ffffff000000) + /* Values for PP (assumes Ks=0, Kp=1) */ /* pp0 will always be 0 for linux */ #define PP_RWXX 0 /* Supervisor read/write, User none */_______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev