In particular,
- avoid dereferencing NULL pointers
- test pointers against NULL, not 0
- test for errout == NULL in the top-level functions (kvm_open, kvm_openfiles,
kvm_open2, etc)
- Replace a realloc and free on failure with reallocf
Found with: devel/cocchinelle
Differential Revision: https://reviews.freebsd.org/D5954
MFC after: 1 week
Reviewed by: jhb
Sponsored by: EMC / Isilon Storage Division
- Add a kvaddr_type to represent kernel virtual addresses instead of
unsigned long.
- Add a struct kvm_nlist which is a stripped down version of struct nlist
that uses kvaddr_t for n_value.
- Add a kvm_native() routine that returns true if an open kvm descriptor
is for a native kernel and memory image.
- Add a kvm_open2() function similar to kvm_openfiles(). It drops the
unused 'swapfile' argument and adds a new function pointer argument for
a symbol resolving function. Native kernels still use _fdnlist() from
libc to resolve symbols if a resolver function is not supplied, but cross
kernels require a resolver.
- Add a kvm_nlist2() function similar to kvm_nlist() except that it uses
struct kvm_nlist instead of struct nlist.
- Add a kvm_read2() function similar to kvm_read() except that it uses
kvaddr_t instead of unsigned long for the kernel virtual address.
- Add a new kvm_arch switch of routines needed by a vmcore backend.
Each backend is responsible for implementing kvm_read2() for a given
vmcore format.
- Use libelf to read headers from ELF kernels and cores (except for
powerpc cores).
- Add internal helper routines for the common page offset hash table used
by the minidump backends.
- Port all of the existing kvm backends to implement a kvm_arch switch and
to be cross-friendly by using private constants instead of ones that
vary by platform (e.g. PAGE_SIZE). Static assertions are present when
a given backend is compiled natively to ensure the private constants
match the real ones.
- Enable all of the existing vmcore backends on all platforms. This means
that libkvm on any platform should be able to perform KVA translation
and read data from a vmcore of any platform.
Tested on: amd64, i386, sparc64 (marius)
Differential Revision: https://reviews.freebsd.org/D3341
physaddr. This should allow for a kernel where PHYSADDR and KERNPHYSADDR
are both undefined.
For now libkvm will use the old method of reading physaddr and kernaddr
to allow it to work with old kernels. This could be removed in the future
when enough time has passed.
Differential Revision: https://reviews.freebsd.org/D939
MFC after: 1 week
- make WARNS=6 clean for archs w/o strict alignment requirments
- add const, ANSIfy, remove unused vars, cast types for comparison
- thanks to differing definitions of VM_MIN_ADDRESS across our archs, we
need to trick the compiler to not complain about signedness. We could
either fix VM_MIN_ADDRESS to always be a simple integer or make the
check conditional on $ARCH.
Closes PRs: kern/42386, kern/83364
Reviewed by: bde
bogusly used the kvm_powerpc.c file as a template for the license, but
then either wrote the code himself, or cribbed it from the kvm_i386
file. The only thing from the kvm_powerpc.c file was the license.
Correct this mistake with his blessing.
returned an lseek offset in a "u_long *" value, which can't express >4GB
offsets on 32 bit machines (eg: PAE). Change to "off_t *" for all.
Support ELF crashdumps on i386 and amd64.
Support PAE crashdumps on i386. This is done by auto-detecting the
presence of the IdlePDPT which means that PAE is active.
I used Marcel's _kvm_pa2off strategy and ELF header reader for ELF support
on amd64. Paul Saab ported the amd64 changes to i386 and we implemented
the PAE support from there.
Note that gdb6 in the src tree uses whatever libkvm supports. If you want
to debug an old crash dump, you might want to keep an old libkvm.so handy
and use LD_PRELOAD or the like. This does not detect the old raw dump
format.
Approved by: re
