crash: remove an unused argument from reserve_crashkernel_generic()

cmdline argument is not used in reserve_crashkernel_generic() so remove
it. Correspondingly, all the callers have been updated as

crash: remove an unused argument from reserve_crashkernel_generic()

cmdline argument is not used in reserve_crashkernel_generic() so remove
it. Correspondingly, all the callers have been updated as well.

No functional change intended.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Sourabh Jain <[email protected]>
Acked-by: Hari Bathini <[email protected]>
Acked-by: Baoquan He <[email protected]>
Cc: Madhavan Srinivasan <[email protected]>
Cc: Mahesh Salgaonkar <[email protected]>
Cc: Michael Ellerman <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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crash: Fix riscv64 crash memory reserve dead loop

On RISCV64 Qemu machine with 512MB memory, cmdline "crashkernel=500M,high"
will cause system stall as below:

Zone ranges:
DMA32 [mem 0x000

crash: Fix riscv64 crash memory reserve dead loop

On RISCV64 Qemu machine with 512MB memory, cmdline "crashkernel=500M,high"
will cause system stall as below:

Zone ranges:
DMA32 [mem 0x0000000080000000-0x000000009fffffff]
Normal empty
Movable zone start for each node
Early memory node ranges
node 0: [mem 0x0000000080000000-0x000000008005ffff]
node 0: [mem 0x0000000080060000-0x000000009fffffff]
Initmem setup node 0 [mem 0x0000000080000000-0x000000009fffffff]
(stall here)

commit 5d99cadf1568 ("crash: fix x86_32 crash memory reserve dead loop
bug") fix this on 32-bit architecture. However, the problem is not
completely solved. If `CRASH_ADDR_LOW_MAX = CRASH_ADDR_HIGH_MAX` on 64-bit
architecture, for example, when system memory is equal to
CRASH_ADDR_LOW_MAX on RISCV64, the following infinite loop will also occur:

-> reserve_crashkernel_generic() and high is true
-> alloc at [CRASH_ADDR_LOW_MAX, CRASH_ADDR_HIGH_MAX] fail
-> alloc at [0, CRASH_ADDR_LOW_MAX] fail and repeatedly
(because CRASH_ADDR_LOW_MAX = CRASH_ADDR_HIGH_MAX).

As Catalin suggested, do not remove the ",high" reservation fallback to
",low" logic which will change arm64's kdump behavior, but fix it by
skipping the above situation similar to commit d2f32f23190b ("crash: fix
x86_32 crash memory reserve dead loop").

After this patch, it print:
cannot allocate crashkernel (size:0x1f400000)

Signed-off-by: Jinjie Ruan <[email protected]>
Suggested-by: Catalin Marinas <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Acked-by: Baoquan He <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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crash: fix crash memory reserve exceed system memory bug

On x86_32 Qemu machine with 1GB memory, the cmdline "crashkernel=4G" is ok
as below:
crashkernel reserved: 0x0000000020000000 - 0x0000000120

crash: fix crash memory reserve exceed system memory bug

On x86_32 Qemu machine with 1GB memory, the cmdline "crashkernel=4G" is ok
as below:
crashkernel reserved: 0x0000000020000000 - 0x0000000120000000 (4096 MB)

It's similar on other architectures, such as ARM32 and RISCV32.

The cause is that the crash_size is parsed and printed with "unsigned long
long" data type which is 8 bytes but allocated used with "phys_addr_t"
which is 4 bytes in memblock_phys_alloc_range().

Fix it by checking if crash_size is greater than system RAM size and
return error if so.

After this patch, there is no above confusing reserve success info.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Jinjie Ruan <[email protected]>
Suggested-by: Mike Rapoport <[email protected]>
Acked-by: Baoquan He <[email protected]>
Cc: Albert Ou <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Paul Walmsley <[email protected]>
Cc: Vivek Goyal <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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crash: fix riscv64 crash memory reserve dead loop

On RISCV64 Qemu machine with 512MB memory, cmdline "crashkernel=500M,high"
will cause system stall as below:

Zone ranges:
DMA32 [mem 0x000

crash: fix riscv64 crash memory reserve dead loop

On RISCV64 Qemu machine with 512MB memory, cmdline "crashkernel=500M,high"
will cause system stall as below:

Zone ranges:
DMA32 [mem 0x0000000080000000-0x000000009fffffff]
Normal empty
Movable zone start for each node
Early memory node ranges
node 0: [mem 0x0000000080000000-0x000000008005ffff]
node 0: [mem 0x0000000080060000-0x000000009fffffff]
Initmem setup node 0 [mem 0x0000000080000000-0x000000009fffffff]
(stall here)

commit 5d99cadf1568 ("crash: fix x86_32 crash memory reserve dead loop
bug") fix this on 32-bit architecture. However, the problem is not
completely solved. If `CRASH_ADDR_LOW_MAX = CRASH_ADDR_HIGH_MAX` on
64-bit architecture, for example, when system memory is equal to
CRASH_ADDR_LOW_MAX on RISCV64, the following infinite loop will also
occur:

-> reserve_crashkernel_generic() and high is true
-> alloc at [CRASH_ADDR_LOW_MAX, CRASH_ADDR_HIGH_MAX] fail
-> alloc at [0, CRASH_ADDR_LOW_MAX] fail and repeatedly
(because CRASH_ADDR_LOW_MAX = CRASH_ADDR_HIGH_MAX).

As Catalin suggested, do not remove the ",high" reservation fallback to
",low" logic which will change arm64's kdump behavior, but fix it by
skipping the above situation similar to commit d2f32f23190b ("crash: fix
x86_32 crash memory reserve dead loop").

After this patch, it print:
cannot allocate crashkernel (size:0x1f400000)

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Jinjie Ruan <[email protected]>
Suggested-by: Catalin Marinas <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Acked-by: Baoquan He <[email protected]>
Cc: Albert Ou <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Paul Walmsley <[email protected]>
Cc: Vivek Goyal <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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crash: remove header files which are included more than once

Following warning is reported, so remove these duplicated header
including:

./kernel/crash_reserve.c: linux/kexec.h is included more tha

crash: remove header files which are included more than once

Following warning is reported, so remove these duplicated header
including:

./kernel/crash_reserve.c: linux/kexec.h is included more than once.

This is just a clean code, no logic changed.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Wenchao Hao <[email protected]>
Acked-by: Baoquan He <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Vivek Goyal <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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crash: add prefix for crash dumping messages

Add pr_fmt() to kernel/crash_core.c to add the module name to debugging
message printed as prefix.

And also add prefix 'crashkernel:' to two lines of me

crash: add prefix for crash dumping messages

Add pr_fmt() to kernel/crash_core.c to add the module name to debugging
message printed as prefix.

And also add prefix 'crashkernel:' to two lines of message printing code
in kernel/crash_reserve.c. In kernel/crash_reserve.c, almost all
debugging messages have 'crashkernel:' prefix or there's keyword
crashkernel at the beginning or in the middle, adding pr_fmt() makes it
redundant.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Baoquan He <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Jiri Slaby <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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crash: use macro to add crashk_res into iomem early for specific arch

There are regression reports[1][2] that crashkernel region on x86_64 can't
be added into iomem tree sometime. This causes the l

crash: use macro to add crashk_res into iomem early for specific arch

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/[email protected]/T/#u

[2]
Question about Address Range Validation in Crash Kernel Allocation
https://lore.kernel.org/all/[email protected]/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 <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Huacai Chen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Bohac <[email protected]>
Cc: Li Huafei <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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kexec: split crashkernel reservation code out from crash_core.c

Patch series "Split crash out from kexec and clean up related config
items", v3.

Motivation:
=============
Previously, LKP reported a

kexec: split crashkernel reservation code out from crash_core.c

Patch series "Split crash out from kexec and clean up related config
items", v3.

Motivation:
=============
Previously, LKP reported a building error. When investigating, it can't
be resolved reasonablly with the present messy kdump config items.

https://lore.kernel.org/oe-kbuild-all/[email protected]/

The kdump (crash dumping) related config items could causes confusions:

Firstly,

CRASH_CORE enables codes including
- crashkernel reservation;
- elfcorehdr updating;
- vmcoreinfo exporting;
- crash hotplug handling;

Now fadump of powerpc, kcore dynamic debugging and kdump all selects
CRASH_CORE, while fadump
- fadump needs crashkernel parsing, vmcoreinfo exporting, and accessing
global variable 'elfcorehdr_addr';
- kcore only needs vmcoreinfo exporting;
- kdump needs all of the current kernel/crash_core.c.

So only enabling PROC_CORE or FA_DUMP will enable CRASH_CORE, this
mislead people that we enable crash dumping, actual it's not.

Secondly,

It's not reasonable to allow KEXEC_CORE select CRASH_CORE.

Because KEXEC_CORE enables codes which allocate control pages, copy
kexec/kdump segments, and prepare for switching. These codes are
shared by both kexec reboot and kdump. We could want kexec reboot,
but disable kdump. In that case, CRASH_CORE should not be selected.

--------------------
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_KEXEC=y
CONFIG_KEXEC_FILE=y
---------------------

Thirdly,

It's not reasonable to allow CRASH_DUMP select KEXEC_CORE.

That could make KEXEC_CORE, CRASH_DUMP are enabled independently from
KEXEC or KEXEC_FILE. However, w/o KEXEC or KEXEC_FILE, the KEXEC_CORE
code built in doesn't make any sense because no kernel loading or
switching will happen to utilize the KEXEC_CORE code.
---------------------
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_CRASH_DUMP=y
---------------------

In this case, what is worse, on arch sh and arm, KEXEC relies on MMU,
while CRASH_DUMP can still be enabled when !MMU, then compiling error is
seen as the lkp test robot reported in above link.

------arch/sh/Kconfig------
config ARCH_SUPPORTS_KEXEC
def_bool MMU

config ARCH_SUPPORTS_CRASH_DUMP
def_bool BROKEN_ON_SMP
---------------------------

Changes:
===========
1, split out crash_reserve.c from crash_core.c;
2, split out vmcore_infoc. from crash_core.c;
3, move crash related codes in kexec_core.c into crash_core.c;
4, remove dependency of FA_DUMP on CRASH_DUMP;
5, clean up kdump related config items;
6, wrap up crash codes in crash related ifdefs on all 8 arch-es
which support crash dumping, except of ppc;

Achievement:
===========
With above changes, I can rearrange the config item logic as below (the right
item depends on or is selected by the left item):

PROC_KCORE -----------> VMCORE_INFO

|----------> VMCORE_INFO
FA_DUMP----|
|----------> CRASH_RESERVE

---->VMCORE_INFO
/
|---->CRASH_RESERVE
KEXEC --| /|
|--> KEXEC_CORE--> CRASH_DUMP-->/-|---->PROC_VMCORE
KEXEC_FILE --| \ |
\---->CRASH_HOTPLUG


KEXEC --|
|--> KEXEC_CORE (for kexec reboot only)
KEXEC_FILE --|

Test
========
On all 8 architectures, including x86_64, arm64, s390x, sh, arm, mips,
riscv, loongarch, I did below three cases of config item setting and
building all passed. Take configs on x86_64 as exampmle here:

(1) Both CONFIG_KEXEC and KEXEC_FILE is unset, then all kexec/kdump
items are unset automatically:
# Kexec and crash features
# CONFIG_KEXEC is not set
# CONFIG_KEXEC_FILE is not set
# end of Kexec and crash features

(2) set CONFIG_KEXEC_FILE and 'make olddefconfig':
---------------
# Kexec and crash features
CONFIG_CRASH_RESERVE=y
CONFIG_VMCORE_INFO=y
CONFIG_KEXEC_CORE=y
CONFIG_KEXEC_FILE=y
CONFIG_CRASH_DUMP=y
CONFIG_CRASH_HOTPLUG=y
CONFIG_CRASH_MAX_MEMORY_RANGES=8192
# end of Kexec and crash features
---------------

(3) unset CONFIG_CRASH_DUMP in case 2 and execute 'make olddefconfig':
------------------------
# Kexec and crash features
CONFIG_KEXEC_CORE=y
CONFIG_KEXEC_FILE=y
# end of Kexec and crash features
------------------------

Note:
For ppc, it needs investigation to make clear how to split out crash
code in arch folder. Hope Hari and Pingfan can help have a look, see if
it's doable. Now, I make it either have both kexec and crash enabled, or
disable both of them altogether.


This patch (of 14):

Both kdump and fa_dump of ppc rely on crashkernel reservation. Move the
relevant codes into separate files: crash_reserve.c,
include/linux/crash_reserve.h.

And also add config item CRASH_RESERVE to control its enabling of the
codes. And update config items which has relationship with crashkernel
reservation.

And also change ifdeffery from CONFIG_CRASH_CORE to CONFIG_CRASH_RESERVE
when those scopes are only crashkernel reservation related.

And also rename arch/XXX/include/asm/{crash_core.h => crash_reserve.h} on
arm64, x86 and risc-v because those architectures' crash_core.h is only
related to crashkernel reservation.

[[email protected]: s/CRASH_RESEERVE/CRASH_RESERVE/, per Klara Modin]
Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Baoquan He <[email protected]>
Acked-by: Hari Bathini <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Pingfan Liu <[email protected]>
Cc: Klara Modin <[email protected]>
Cc: Michael Kelley <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Yang Li <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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