Patch series "Allow to kexec with initramfs larger than 2G", v2.
Currently, the largest initramfs that is supported by kexec_file_load()
syscall is 2G.
This is because kernel_read_file() returns int, and is limited to INT_MAX
or 2G.
On the other hand, there are kexec based boot loaders (i.e. u-root), that
may need to boot netboot images that might be larger than 2G.
The first patch changes the return type from int to ssize_t in
kernel_read_file* functions.
The second patch increases the maximum initramfs file size to 4G.
Tested: verified that can kexec_file_load() works with 4G initramfs
on x86_64.
This patch (of 2):
Currently, the maximum file size that is supported is 2G. This may be too
small in some cases. For example, kexec_file_load() system call loads
initramfs. In some netboot cases initramfs can be rather large.
Allow to use up-to ssize_t bytes. The callers still can limit the maximum
file size via buf_size.
Link: https://lkml.kernel.org/r/20220527025535.3953665-1-pasha.tatashin@soleen.com
Link: https://lkml.kernel.org/r/20220527025535.3953665-2-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Baoquan He <bhe@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
dabba87229