I didn't check XEN HYPER MODE, I don't have XEN.
If we need similar statement "if (kvaddr < MODULES_END)"
 please add inside in "if (XEN_HYPER_MODE())" (1859@x86_64_kvtop)




>From ed300b74998e0923313e4fd14b9a41e305942b44 Mon Sep 17 00:00:00 2001
From: Nakajima Akira <[email protected]>
Date: Tue, 22 Dec 2015 15:46:42 +0900
Subject: [PATCH] Fix that particular kvaddr is converted to wrong paddr

BUG INFO
Particular kvaddr is converted to wrong paddr.
You can see this bug on RHEL6_x86_64. (at present only RHEL6)
 (I checked RHEL5, RHEL7, Fedora21, Fedora23)


from /proc/kallsyms
ffffffffff6008c0 D __jiffies

/////////// wrong ///////////
crash> vtop ffffffffff6008c0
VIRTUAL           PHYSICAL        
ffffffffff6008c0  7f6008c0        

      PAGE        PHYSICAL      MAPPING       INDEX CNT FLAGS
ffffea00000623b8   1c11000                0        0  1 20000000000400 reserved


crash> rd ffffffffff6008c0
ffffffffff6008c0:  0000000000000000                    ........


/////////// correct ///////////
crash> vtop ffffffffff6008c0
VIRTUAL           PHYSICAL        
ffffffffff6008c0  1c118c0         

      PAGE        PHYSICAL      MAPPING       INDEX CNT FLAGS
ffffea00000623b8   1c11000                0        0  1 20000000000400 reserved


crash> rd ffffffffff6008c0
ffffffffff6008c0:  00000000ffffe43a                    :.......

Reported-by: Nakajima Akira <[email protected]>
Signed-off-by: Nakajima Akira <[email protected]>

---
 x86_64.c |   28 +++++++++++++++-------------
 1 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/x86_64.c b/x86_64.c
index ff6fdd5..dab4d43 100644
--- a/x86_64.c
+++ b/x86_64.c
@@ -1872,19 +1872,21 @@ x86_64_kvtop(struct task_context *tc, ulong kvaddr, 
physaddr_t *paddr, int verbo
                                fprintf(fp, "PAGE DIRECTORY: %lx\n", *pml4);
                }
        } else {
-               if (!vt->vmalloc_start) {
-                       *paddr = x86_64_VTOP(kvaddr);
-                       return TRUE;
-               }
-
-               if (!IS_VMALLOC_ADDR(kvaddr)) {
-                       *paddr = x86_64_VTOP(kvaddr);
-                       if (!verbose)
-                               return TRUE;
-               }
-
-               if (XEN() && (kt->xen_flags & WRITABLE_PAGE_TABLES))
-                       return (x86_64_kvtop_xen_wpt(tc, kvaddr, paddr, 
verbose));
+               if (kvaddr < MODULES_END) {
+                       if (!vt->vmalloc_start) {
+                               *paddr = x86_64_VTOP(kvaddr);
+                               return TRUE;
+                       }
+       
+                       if (!IS_VMALLOC_ADDR(kvaddr)) {
+                               *paddr = x86_64_VTOP(kvaddr);
+                               if (!verbose)
+                                       return TRUE;
+                       }
+       
+                       if (XEN() && (kt->xen_flags & WRITABLE_PAGE_TABLES))
+                               return (x86_64_kvtop_xen_wpt(tc, kvaddr, paddr, 
verbose));
+               }
 
                /*      
                 *  pgd = pgd_offset_k(addr);
-- 
1.7.1

From ed300b74998e0923313e4fd14b9a41e305942b44 Mon Sep 17 00:00:00 2001
From: Nakajima Akira <[email protected]>
Date: Tue, 22 Dec 2015 15:46:42 +0900
Subject: [PATCH] Fix that particular kvaddr is converted to wrong paddr

BUG INFO
Particular kvaddr is converted to wrong paddr.
You can see this bug on RHEL6_x86_64. (at present only RHEL6)
 (I checked RHEL5, RHEL7, Fedora21, Fedora23)


from /proc/kallsyms
ffffffffff6008c0 D __jiffies

/////////// wrong ///////////
crash> vtop ffffffffff6008c0
VIRTUAL           PHYSICAL        
ffffffffff6008c0  7f6008c0        

      PAGE        PHYSICAL      MAPPING       INDEX CNT FLAGS
ffffea00000623b8   1c11000                0        0  1 20000000000400 reserved


crash> rd ffffffffff6008c0
ffffffffff6008c0:  0000000000000000                    ........


/////////// correct ///////////
crash> vtop ffffffffff6008c0
VIRTUAL           PHYSICAL        
ffffffffff6008c0  1c118c0         

      PAGE        PHYSICAL      MAPPING       INDEX CNT FLAGS
ffffea00000623b8   1c11000                0        0  1 20000000000400 reserved


crash> rd ffffffffff6008c0
ffffffffff6008c0:  00000000ffffe43a                    :.......

Reported-by: Nakajima Akira <[email protected]>
Signed-off-by: Nakajima Akira <[email protected]>

---
 x86_64.c |   28 +++++++++++++++-------------
 1 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/x86_64.c b/x86_64.c
index ff6fdd5..dab4d43 100644
--- a/x86_64.c
+++ b/x86_64.c
@@ -1872,19 +1872,21 @@ x86_64_kvtop(struct task_context *tc, ulong kvaddr, 
physaddr_t *paddr, int verbo
                                fprintf(fp, "PAGE DIRECTORY: %lx\n", *pml4);
                }
        } else {
-               if (!vt->vmalloc_start) {
-                       *paddr = x86_64_VTOP(kvaddr);
-                       return TRUE;
-               }
-
-               if (!IS_VMALLOC_ADDR(kvaddr)) {
-                       *paddr = x86_64_VTOP(kvaddr);
-                       if (!verbose)
-                               return TRUE;
-               }
-
-               if (XEN() && (kt->xen_flags & WRITABLE_PAGE_TABLES))
-                       return (x86_64_kvtop_xen_wpt(tc, kvaddr, paddr, 
verbose));
+               if (kvaddr < MODULES_END) {
+                       if (!vt->vmalloc_start) {
+                               *paddr = x86_64_VTOP(kvaddr);
+                               return TRUE;
+                       }
+       
+                       if (!IS_VMALLOC_ADDR(kvaddr)) {
+                               *paddr = x86_64_VTOP(kvaddr);
+                               if (!verbose)
+                                       return TRUE;
+                       }
+       
+                       if (XEN() && (kt->xen_flags & WRITABLE_PAGE_TABLES))
+                               return (x86_64_kvtop_xen_wpt(tc, kvaddr, paddr, 
verbose));
+               }
 
                /*      
                 *  pgd = pgd_offset_k(addr);
-- 
1.7.1

--
Crash-utility mailing list
[email protected]
https://www.redhat.com/mailman/listinfo/crash-utility

Reply via email to