From: "Sachin P. Sant" <sachinp@in•ibm.com>
To: Olof Johansson <olof@lixom•net>, Paul Mackerras <paulus@samba•org>
Cc: linuxppc-dev@ozlabs•org, kexec@lists•infradead.org,
Milton Miller II <miltonm@us•ibm.com>
Subject: [Patch ] Kexec/Kdump support - POWER6
Date: Fri, 25 May 2007 14:25:36 +0530 [thread overview]
Message-ID: <4656A488.2020507@in.ibm.com> (raw)
In-Reply-To: <20070524142133.GA13191@lixom.net>
[-- Attachment #1: Type: text/plain, Size: 460 bytes --]
Olof Johansson wrote:
> As Paul says above, you need to check for failures and compare the VSID
> and possibly unhash it anyway in case of non-match. Otherwise if the
> kernel ever starts using 1TB segments for regular use, those pages will
> never be unhashed. I don't see your code doing that now.
>
>
How about the following patch ?
Thanks
-Sachin
Signed-off-by : Sachin Sant <sachinp@in•ibm.com>
Signed-off-by : Mohan Kumar M <mohan@in•ibm.com>
---
[-- Attachment #2: kexec-kdump-support-on-POWER6 --]
[-- Type: text/plain, Size: 2524 bytes --]
* 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 <sachinp@in•ibm.com>
Signed-off-by : Mohan Kumar M <mohan@in•ibm.com>
---
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 2007-05-25 14:09:59.000000000 +0530
@@ -369,16 +369,30 @@ static long pSeries_lpar_hpte_remove(uns
return -1;
}
+#define VRMA_HPTE_B_1TB ASM_CONST(0x4000000000000000)
+#define VRMA_MASK ASM_CONST(0x4001ffffff)
+
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, VRMA_HPTE_B_1TB,
+ &dummy1, &dummy2);
+ if (lpar_rc == H_NOT_FOUND) {
+ lpar_rc = plpar_pte_read_raw(0, i, &dword0, &dummy1);
+ if (!lpar_rc &&
+ (((dword0 >> 24) & VRMA_MASK) != 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)
{
next prev parent reply other threads:[~2007-05-25 8:55 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-05-22 12:22 [Patch 0/2] Kexec/Kdump support POWER6 Sachin P. Sant
2007-05-22 12:24 ` [Patch 1/2] " Sachin P. Sant
2007-05-22 12:26 ` [Patch 2/2] " Sachin P. Sant
2007-05-22 15:34 ` Olof Johansson
2007-05-23 5:13 ` Sachin P. Sant
2007-05-23 5:14 ` Sachin P. Sant
2007-05-23 9:37 ` [Patch 2/2] Kexec/Kdump support - POWER6 Sachin P. Sant
2007-05-23 10:55 ` Paul Mackerras
2007-05-24 12:17 ` Mohan Kumar M
2007-05-24 14:21 ` Olof Johansson
2007-05-25 8:55 ` Sachin P. Sant [this message]
2007-05-25 22:43 ` [Patch ] " Benjamin Herrenschmidt
2007-05-28 11:40 ` Sachin P. Sant
2007-05-28 21:31 ` Benjamin Herrenschmidt
2007-05-29 6:18 ` Sachin P. Sant
2007-05-29 6:58 ` Benjamin Herrenschmidt
2007-05-29 10:14 ` Michael Ellerman
2007-05-29 11:06 ` Stephen Rothwell
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