s390/mm/ptdump: Fix handling of identity mapping area

[ Upstream commit 373953444ce542db43535861fb8ebf3a1e05669c ]

Since virtual and real addresses are not the same anymore the
assumption that the kernel image is contained within the identity
mapping is also not true anymore.

Fix this by adding two explicit areas and at the correct locations: one
for the 8kb lowcore area, and one for the identity mapping.

Fixes: c98d2ecae08f ("s390/mm: Uncouple physical vs virtual address spaces")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/arch/s390/mm/dump_pagetables.c b/arch/s390/mm/dump_pagetables.c
index ffd07ed7b4af88968caac3861076217bd79d6933..9d0805d6dc1b233cf1f4d83ceaacd5a4600cc156 100644 (file)
--- a/arch/s390/mm/dump_pagetables.c
+++ b/arch/s390/mm/dump_pagetables.c
@@ -20,8 +20,8 @@ struct addr_marker {
 };
 
 enum address_markers_idx {
-       IDENTITY_BEFORE_NR = 0,
-       IDENTITY_BEFORE_END_NR,
+       LOWCORE_START_NR = 0,
+       LOWCORE_END_NR,
        AMODE31_START_NR,
        AMODE31_END_NR,
        KERNEL_START_NR,
@@ -30,8 +30,8 @@ enum address_markers_idx {
        KFENCE_START_NR,
        KFENCE_END_NR,
 #endif
-       IDENTITY_AFTER_NR,
-       IDENTITY_AFTER_END_NR,
+       IDENTITY_START_NR,
+       IDENTITY_END_NR,
        VMEMMAP_NR,
        VMEMMAP_END_NR,
        VMALLOC_NR,
@@ -49,8 +49,10 @@ enum address_markers_idx {
 };
 
 static struct addr_marker address_markers[] = {
-       [IDENTITY_BEFORE_NR]    = {0, "Identity Mapping Start"},
-       [IDENTITY_BEFORE_END_NR] = {(unsigned long)_stext, "Identity Mapping End"},
+       [LOWCORE_START_NR]      = {0, "Lowcore Start"},
+       [LOWCORE_END_NR]        = {0, "Lowcore End"},
+       [IDENTITY_START_NR]     = {0, "Identity Mapping Start"},
+       [IDENTITY_END_NR]       = {0, "Identity Mapping End"},
        [AMODE31_START_NR]      = {0, "Amode31 Area Start"},
        [AMODE31_END_NR]        = {0, "Amode31 Area End"},
        [KERNEL_START_NR]       = {(unsigned long)_stext, "Kernel Image Start"},
@@ -59,8 +61,6 @@ static struct addr_marker address_markers[] = {
        [KFENCE_START_NR]       = {0, "KFence Pool Start"},
        [KFENCE_END_NR]         = {0, "KFence Pool End"},
 #endif
-       [IDENTITY_AFTER_NR]     = {(unsigned long)_end, "Identity Mapping Start"},
-       [IDENTITY_AFTER_END_NR] = {0, "Identity Mapping End"},
        [VMEMMAP_NR]            = {0, "vmemmap Area Start"},
        [VMEMMAP_END_NR]        = {0, "vmemmap Area End"},
        [VMALLOC_NR]            = {0, "vmalloc Area Start"},
@@ -290,7 +290,10 @@ static int pt_dump_init(void)
         */
        max_addr = (S390_lowcore.kernel_asce.val & _REGION_ENTRY_TYPE_MASK) >> 2;
        max_addr = 1UL << (max_addr * 11 + 31);
-       address_markers[IDENTITY_AFTER_END_NR].start_address = ident_map_size;
+       address_markers[LOWCORE_START_NR].start_address = 0;
+       address_markers[LOWCORE_END_NR].start_address = sizeof(struct lowcore);
+       address_markers[IDENTITY_START_NR].start_address = __identity_base;
+       address_markers[IDENTITY_END_NR].start_address = __identity_base + ident_map_size;
        address_markers[AMODE31_START_NR].start_address = (unsigned long)__samode31;
        address_markers[AMODE31_END_NR].start_address = (unsigned long)__eamode31;
        address_markers[MODULES_NR].start_address = MODULES_VADDR;