6.8-stable review patch. If anyone has any objections, please let me know.
------------------
From: Baoquan He <bhe@xxxxxxxxxx>
commit 32fbe5246582af4f611ccccee33fd6e559087252 upstream.
There are regression reports[1][2] that crashkernel region on x86_64 can't
be added into iomem tree sometime. This causes the later failure of kdump
loading.
This happened after commit 4a693ce65b18 ("kdump: defer the insertion of
crashkernel resources") was merged.
Even though, these reported issues are proved to be related to other
component, they are just exposed after above commmit applied, I still
would like to keep crashk_res and crashk_low_res being added into iomem
early as before because the early adding has been always there on x86_64
and working very well. For safety of kdump, Let's change it back.
Here, add a macro HAVE_ARCH_ADD_CRASH_RES_TO_IOMEM_EARLY to limit that
only ARCH defining the macro can have the early adding
crashk_res/_low_res into iomem. Then define
HAVE_ARCH_ADD_CRASH_RES_TO_IOMEM_EARLY on x86 to enable it.
Note: In reserve_crashkernel_low(), there's a remnant of crashk_low_res
handling which was mistakenly added back in commit 85fcde402db1 ("kexec:
split crashkernel reservation code out from crash_core.c").
[1]
[PATCH V2] x86/kexec: do not update E820 kexec table for setup_data
https://lore.kernel.org/all/Zfv8iCL6CT2JqLIC@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx/T/#u
[2]
Question about Address Range Validation in Crash Kernel Allocation
https://lore.kernel.org/all/4eeac1f733584855965a2ea62fa4da58@xxxxxxxxxx/T/#u
Link: https://lkml.kernel.org/r/ZgDYemRQ2jxjLkq+@MiWiFi-R3L-srv
Fixes: 4a693ce65b18 ("kdump: defer the insertion of crashkernel resources")
Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
Cc: Dave Young <dyoung@xxxxxxxxxx>
Cc: Huacai Chen <chenhuacai@xxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jiri Bohac <jbohac@xxxxxxx>
Cc: Li Huafei <lihuafei1@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/include/asm/crash_core.h | 2 ++
kernel/crash_core.c | 8 ++++++++
2 files changed, 10 insertions(+)
--- a/arch/x86/include/asm/crash_core.h
+++ b/arch/x86/include/asm/crash_core.h
@@ -39,4 +39,6 @@ static inline unsigned long crash_low_si
#endif
}
+#define HAVE_ARCH_ADD_CRASH_RES_TO_IOMEM_EARLY
+
#endif /* _X86_CRASH_CORE_H */
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -376,6 +376,9 @@ static int __init reserve_crashkernel_lo
crashk_low_res.start = low_base;
crashk_low_res.end = low_base + low_size - 1;
+#ifdef HAVE_ARCH_ADD_CRASH_RES_TO_IOMEM_EARLY
+ insert_resource(&iomem_resource, &crashk_low_res);
+#endif
#endif
return 0;
}
@@ -457,8 +460,12 @@ retry:
crashk_res.start = crash_base;
crashk_res.end = crash_base + crash_size - 1;
+#ifdef HAVE_ARCH_ADD_CRASH_RES_TO_IOMEM_EARLY
+ insert_resource(&iomem_resource, &crashk_res);
+#endif
}
+#ifndef HAVE_ARCH_ADD_CRASH_RES_TO_IOMEM_EARLY
static __init int insert_crashkernel_resources(void)
{
if (crashk_res.start < crashk_res.end)
@@ -471,6 +478,7 @@ static __init int insert_crashkernel_res
}
early_initcall(insert_crashkernel_resources);
#endif
+#endif
int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
void **addr, unsigned long *sz)
