sadump: fix failure of reading memory when 5-level paging is enabled

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2184284
Resolves: rhbz#2184284
Upstream: makedumpfile

commit 58553ad03187f0cf208d6c4a0dc026c6338e5edd
Author: Daisuke Hatayama (Fujitsu) <d.hatayama@fujitsu.com>
Date:   Wed Mar 29 12:44:10 2023 +0000

    [PATCH] sadump: fix failure of reading memory when 5-level paging is enabled

    makedumpfile fails as follows for memory dumps collected by sadump
    when 5-level paging is enabled on the corresponding systems:

        # makedumpfile -l -d 31 -x ./vmlinux ./dump.sadump dump.sadump-ld31
        __vtop4_x86_64: Can't get a valid pgd.
        ...snip...
        __vtop4_x86_64: Can't get a valid pgd.
        calc_kaslr_offset: failed to calculate kaslr_offset and phys_base; default to 0
        __vtop4_x86_64: Can't get a valid pgd.
        readmem: Can't convert a virtual address(ffffffff82fce960) to physical address.
        readmem: type_addr: 0, addr:ffffffff82fce960, size:1024
        cpu_online_mask_init: Can't read cpu_online_mask memory.

        makedumpfile Failed.

    This is because 5-level paging support has not been done yet for
    sadump; the work of the 5-level paging support was done by the commit
    30a3214a7193e94c551c0cebda5918a72a35c589 (PATCH 4/4 arch/x86_64: Add
    5-level paging support) but that was focused on the core part only.

    Having said that, most of things has already been finished in the
    commit. What needs to be newly added for sadump is just how to check
    if 5-level paging is enabled for a given memory dump.

    For that purpose, let's refer to CR4.LA57, bit 12 of CR4, representing
    whether 5-level paging is enabled or not. We can do this because
    memory dumps collected by sadump have SMRAM as note information and
    they include CR4 together with the other control registers.

    Signed-off-by: HATAYAMA Daisuke <d.hatayama@fujitsu.com>

Signed-off-by: Pingfan Liu <piliu@redhat.com>

kexec-tools-2.0.26-makedumpfile-sadump-fix-failure-of-reading-memory-when-5-le.patch

@@ -0,0 +1,72 @@
+From 58553ad03187f0cf208d6c4a0dc026c6338e5edd Mon Sep 17 00:00:00 2001
+From: "Daisuke Hatayama (Fujitsu)" <d.hatayama@fujitsu.com>
+Date: Wed, 29 Mar 2023 12:44:10 +0000
+Subject: [PATCH] [PATCH] sadump: fix failure of reading memory when 5-level
+ paging is enabled
+
+makedumpfile fails as follows for memory dumps collected by sadump
+when 5-level paging is enabled on the corresponding systems:
+
+    # makedumpfile -l -d 31 -x ./vmlinux ./dump.sadump dump.sadump-ld31
+    __vtop4_x86_64: Can't get a valid pgd.
+    ...snip...
+    __vtop4_x86_64: Can't get a valid pgd.
+    calc_kaslr_offset: failed to calculate kaslr_offset and phys_base; default to 0
+    __vtop4_x86_64: Can't get a valid pgd.
+    readmem: Can't convert a virtual address(ffffffff82fce960) to physical address.
+    readmem: type_addr: 0, addr:ffffffff82fce960, size:1024
+    cpu_online_mask_init: Can't read cpu_online_mask memory.
+
+    makedumpfile Failed.
+
+This is because 5-level paging support has not been done yet for
+sadump; the work of the 5-level paging support was done by the commit
+30a3214a7193e94c551c0cebda5918a72a35c589 (PATCH 4/4 arch/x86_64: Add
+5-level paging support) but that was focused on the core part only.
+
+Having said that, most of things has already been finished in the
+commit. What needs to be newly added for sadump is just how to check
+if 5-level paging is enabled for a given memory dump.
+
+For that purpose, let's refer to CR4.LA57, bit 12 of CR4, representing
+whether 5-level paging is enabled or not. We can do this because
+memory dumps collected by sadump have SMRAM as note information and
+they include CR4 together with the other control registers.
+
+Signed-off-by: HATAYAMA Daisuke <d.hatayama@fujitsu.com>
+---
+ sadump_info.c | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/makedumpfile-1.7.2/sadump_info.c b/makedumpfile-1.7.2/sadump_info.c
+index adfa8dc..2c44068 100644
+--- a/makedumpfile-1.7.2/sadump_info.c
++++ b/makedumpfile-1.7.2/sadump_info.c
+@@ -1362,6 +1362,7 @@ static int linux_banner_sanity_check(ulong cr3)
+ #define PTI_USER_PGTABLE_BIT		(info->page_shift)
+ #define PTI_USER_PGTABLE_MASK		(1 << PTI_USER_PGTABLE_BIT)
+ #define CR3_PCID_MASK			0xFFFull
++#define CR4_LA57			(1 << 12)
+ int
+ calc_kaslr_offset(void)
+ {
+@@ -1397,6 +1398,8 @@ calc_kaslr_offset(void)
+ 		else
+ 			cr3 = smram.Cr3 & ~CR3_PCID_MASK;
+ 
++		NUMBER(pgtable_l5_enabled) = !!(smram.Cr4 & CR4_LA57);
++
+ 		/* Convert virtual address of IDT table to physical address */
+ 		idtr_paddr = vtop4_x86_64_pagetable(idtr, cr3);
+ 		if (idtr_paddr == NOT_PADDR) {
+@@ -1417,6 +1420,7 @@ calc_kaslr_offset(void)
+ 
+ 		DEBUG_MSG("sadump: idtr=%" PRIx64 "\n", idtr);
+ 		DEBUG_MSG("sadump: cr3=%" PRIx64 "\n", cr3);
++		DEBUG_MSG("sadump: cr4=%" PRIx32 "\n", smram.Cr4);
+ 		DEBUG_MSG("sadump: idtr(phys)=%" PRIx64 "\n", idtr_paddr);
+ 		DEBUG_MSG("sadump: devide_error(vmlinux)=%lx\n",
+ 			  divide_error_vmlinux);
+-- 
+2.31.1
+

kexec-tools.spec

@@ -111,6 +111,7 @@ Patch602: rhelonly-kexec-tools-2.0.18-eppic-fix-issues-with-hardening-flags.patc
 
 # Patches 701 onward for makedumpfile
 Patch701: rhelonly-kexec-tools-2.0.20-makedumpfile-arm64-Add-support-for-ARMv8.2-LVA-52-bi.patch
+Patch702: kexec-tools-2.0.26-makedumpfile-sadump-fix-failure-of-reading-memory-when-5-le.patch
 
 %description
 kexec-tools provides /usr/sbin/kexec binary that facilitates a new
@@ -130,6 +131,7 @@ tar -z -x -v -f %{SOURCE19}
 %patch602 -p1
 
 %patch701 -p1
+%patch702 -p1
 
 %ifarch ppc
 %define archdef ARCH=ppc