The command's usage:
dump-guest-memory [-p] protocol [begin] [length]
The supported protocol can be file or fd:
1. file: the protocol starts with "file:", and the following string is
the file's path.
2. fd: the protocol starts with "fd:", and the following string is the
fd's name.
Note:
1. If you want to use gdb to process the core, please specify -p option.
The reason why the -p option is not default is:
a. guest machine in a catastrophic state can have corrupted memory,
which we cannot trust.
b. The guest machine can be in read-mode even if paging is enabled.
For example: the guest machine uses ACPI to sleep, and ACPI sleep
state goes in real-mode.
2. If you don't want to dump all guest's memory, please specify the start
physical address and the length.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
crash does not need the virtual address and physical address mapping, and the
mapping does not include the memory that is not referenced by the page table.
crash does not use the virtual address, so we can create the mapping for all
physical memory(virtual address is always 0). This patch provides a API to do
this thing, and it will be used in the following patch.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Add API to get all virtual address and physical address mapping.
If the guest doesn't use paging, the virtual address is equal to the phyical
address. The virtual address and physical address mapping is for gdb's user, and
it does not include the memory that is not referenced by the page table. So if
you want to use crash to anaylze the vmcore, please do not specify -p option.
the reason why the -p option is not default explicitly: guest machine in a
catastrophic state can have corrupted memory, which we cannot trust.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Walk cpu's page table and collect all virtual address and physical address mapping.
Then, add these mapping into memory mapping list. If the guest does not use paging,
it will do nothing. Note: the I/O memory will be skipped.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
The memory mapping list stores virtual address and physical address mapping.
The virtual address and physical address are contiguous in the mapping.
The folloing patch will use this information to create PT_LOAD in the vmcore.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
