From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id D0DAADDF82 for ; Wed, 30 May 2007 21:43:17 +1000 (EST) Subject: Re: [Patch ] Kexec Kdump support for POWER6 From: Benjamin Herrenschmidt To: sachinp@in.ibm.com In-Reply-To: <465D099B.3020207@in.ibm.com> References: <465D099B.3020207@in.ibm.com> Content-Type: text/plain Date: Wed, 30 May 2007 21:43:03 +1000 Message-Id: <1180525383.19517.264.camel@localhost.localdomain> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org, Paul Mackerras List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 > Signed-off-by : Mohan Kumar M Acked-by: Benjamin Herrenschmidt > --- > 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