6.8-stable review patch. If anyone has any objections, please let me know.
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From: Baoquan He bhe@redhat.com
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@darkstar.users.ipa.redhat.com/T...
[2] Question about Address Range Validation in Crash Kernel Allocation https://lore.kernel.org/all/4eeac1f733584855965a2ea62fa4da58@huawei.com/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@redhat.com Cc: Dave Young dyoung@redhat.com Cc: Huacai Chen chenhuacai@loongson.cn Cc: Ingo Molnar mingo@kernel.org Cc: Jiri Bohac jbohac@suse.cz Cc: Li Huafei lihuafei1@huawei.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Baoquan He bhe@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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)