[Crash-utility] [PATCH 3/5] Use XEN_MACHINE_ADDR command flag instead of overriding readmem
Petr Tesarik
ptesarik at suse.com
Thu Sep 24 16:17:10 UTC 2015
The intention is to switch off physical-to-machine address translation
temporarily. Overriding readmem works, but only for a single file
format. Using the flag is a better solution, because it does not
add a dependency on a single file format.
Unsetting the flag (rather than restoring it) is safe, because these
functions are not called if XEN_MACHINE_ADDR is set in pc->curcmd_flags.
Signed-off-by: Petr Tesarik <ptesarik at suse.com>
---
ia64.c | 22 ++++++++++------------
x86.c | 15 +++++++--------
x86_64.c | 15 +++++++--------
xen_dom0.c | 12 ++++++++++--
4 files changed, 34 insertions(+), 30 deletions(-)
diff --git a/ia64.c b/ia64.c
index 60fcf20..2e1d15f 100644
--- a/ia64.c
+++ b/ia64.c
@@ -3983,13 +3983,12 @@ static int
ia64_xen_kdump_p2m_create(struct xen_kdump_data *xkd)
{
/*
- * Temporarily read physical (machine) addresses from vmcore by
- * going directly to read_netdump() instead of via read_kdump().
+ * Temporarily read physical (machine) addresses from vmcore.
*/
- pc->readmem = read_netdump;
+ pc->curcmd_flags |= XEN_MACHINE_ADDR;
if (CRASHDEBUG(1)) {
- fprintf(fp, "readmem (temporary): read_netdump()\n");
+ fprintf(fp, "readmem (temporary): force XEN_MACHINE_ADDR\n");
fprintf(fp, "ia64_xen_kdump_p2m_create: p2m_mfn: %lx\n", xkd->p2m_mfn);
}
@@ -4002,9 +4001,9 @@ ia64_xen_kdump_p2m_create(struct xen_kdump_data *xkd)
xkd->p2m_frames = PAGESIZE()/sizeof(ulong);
- pc->readmem = read_kdump;
+ pc->curcmd_flags &= ~XEN_MACHINE_ADDR;
if (CRASHDEBUG(1))
- fprintf(fp, "readmem (restore): read_kdump()\n");
+ fprintf(fp, "readmem (restore): p2m translation\n");
return TRUE;
}
@@ -4017,12 +4016,11 @@ ia64_xen_kdump_p2m(struct xen_kdump_data *xkd, physaddr_t pseudo)
physaddr_t paddr;
/*
- * Temporarily read physical (machine) addresses from vmcore by
- * going directly to read_netdump() instead of via read_kdump().
+ * Temporarily read physical (machine) addresses from vmcore.
*/
- pc->readmem = read_netdump;
+ pc->curcmd_flags |= XEN_MACHINE_ADDR;
if (CRASHDEBUG(1))
- fprintf(fp, "readmem (temporary): read_netdump()\n");
+ fprintf(fp, "readmem (temporary): force XEN_MACHINE_ADDR\n");
xkd->accesses += 2;
@@ -4074,9 +4072,9 @@ ia64_xen_kdump_p2m(struct xen_kdump_data *xkd, physaddr_t pseudo)
paddr = (paddr & _PFN_MASK) | PAGEOFFSET(pseudo);
out:
- pc->readmem = read_kdump;
+ pc->curcmd_flags &= ~XEN_MACHINE_ADDR;
if (CRASHDEBUG(1))
- fprintf(fp, "readmem (restore): read_kdump()\n");
+ fprintf(fp, "readmem (restore): p2m translation\n");
return paddr;
}
diff --git a/x86.c b/x86.c
index f5a0275..54ce7a5 100644
--- a/x86.c
+++ b/x86.c
@@ -4541,12 +4541,11 @@ x86_xen_kdump_p2m_create(struct xen_kdump_data *xkd)
int mfns[MAX_X86_FRAMES] = { 0 };
/*
- * Temporarily read physical (machine) addresses from vmcore by
- * going directly to read_netdump() instead of via read_kdump().
+ * Temporarily read physical (machine) addresses from vmcore.
*/
- pc->readmem = read_netdump;
+ pc->curcmd_flags |= XEN_MACHINE_ADDR;
if (CRASHDEBUG(1))
- fprintf(fp, "readmem (temporary): read_netdump()\n");
+ fprintf(fp, "readmem (temporary): force XEN_MACHINE_ADDR\n");
if (xkd->flags & KDUMP_CR3)
goto use_cr3;
@@ -4623,9 +4622,9 @@ x86_xen_kdump_p2m_create(struct xen_kdump_data *xkd)
fprintf(fp, "\n");
}
- pc->readmem = read_kdump;
+ pc->curcmd_flags &= ~XEN_MACHINE_ADDR;
if (CRASHDEBUG(1))
- fprintf(fp, "readmem (restore): read_kdump()\n");
+ fprintf(fp, "readmem (restore): p2m translation\n");
return TRUE;
@@ -4714,9 +4713,9 @@ use_cr3:
machdep->last_ptbl_read = 0;
machdep->last_pmd_read = 0;
machdep->last_pgd_read = 0;
- pc->readmem = read_kdump;
+ pc->curcmd_flags &= ~XEN_MACHINE_ADDR;
if (CRASHDEBUG(1))
- fprintf(fp, "readmem (restore): read_kdump()\n");
+ fprintf(fp, "readmem (restore): p2m translation\n");
return TRUE;
}
diff --git a/x86_64.c b/x86_64.c
index 975354d..ff6fdd5 100644
--- a/x86_64.c
+++ b/x86_64.c
@@ -5748,12 +5748,11 @@ x86_64_xen_kdump_p2m_create(struct xen_kdump_data *xkd)
struct syment *sp;
/*
- * Temporarily read physical (machine) addresses from vmcore by
- * going directly to read_netdump() instead of via read_kdump().
+ * Temporarily read physical (machine) addresses from vmcore.
*/
- pc->readmem = read_netdump;
+ pc->curcmd_flags |= XEN_MACHINE_ADDR;
if (CRASHDEBUG(1))
- fprintf(fp, "readmem (temporary): read_netdump()\n");
+ fprintf(fp, "readmem (temporary): force XEN_MACHINE_ADDR\n");
if (xkd->flags & KDUMP_CR3)
goto use_cr3;
@@ -5813,9 +5812,9 @@ x86_64_xen_kdump_p2m_create(struct xen_kdump_data *xkd)
fprintf(fp, "\n");
}
- pc->readmem = read_kdump;
+ pc->curcmd_flags &= ~XEN_MACHINE_ADDR;
if (CRASHDEBUG(1))
- fprintf(fp, "readmem (restore): read_kdump()\n");
+ fprintf(fp, "readmem (restore): p2m translation\n");
return TRUE;
@@ -5882,9 +5881,9 @@ use_cr3:
machdep->last_pgd_read = 0;
machdep->last_ptbl_read = 0;
machdep->last_pmd_read = 0;
- pc->readmem = read_kdump;
+ pc->curcmd_flags &= ~XEN_MACHINE_ADDR;
if (CRASHDEBUG(1))
- fprintf(fp, "readmem (restore): read_kdump()\n");
+ fprintf(fp, "readmem (restore): p2m translation\n");
return TRUE;
}
diff --git a/xen_dom0.c b/xen_dom0.c
index 826a90b..7c9c76e 100644
--- a/xen_dom0.c
+++ b/xen_dom0.c
@@ -206,12 +206,20 @@ xen_kdump_p2m(physaddr_t pseudo)
if (mfn_frame == xkd->last_mfn_read)
xkd->cache_hits++;
else {
+ int res;
+
if (CRASHDEBUG(8))
fprintf(fp, "xen_kdump_p2m: paddr/pfn: %llx/%lx: "
"read mfn_frame: %llx\n",
(ulonglong)pseudo, pfn, PTOB(mfn_frame));
- if (read_netdump(0, xkd->page, PAGESIZE(), 0,
- (physaddr_t)PTOB(mfn_frame)) != PAGESIZE())
+
+ pc->curcmd_flags |= XEN_MACHINE_ADDR;
+ res = readmem((physaddr_t)PTOB(mfn_frame), PHYSADDR,
+ xkd->page, PAGESIZE(),
+ "xen_kdump_p2m mfn frame", RETURN_ON_ERROR);
+ pc->curcmd_flags &= ~XEN_MACHINE_ADDR;
+
+ if (!res)
return P2M_FAILURE;
}
--
2.1.4
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