diff options
author | Philipp Rudo <prudo@linux.vnet.ibm.com> | 2018-04-14 01:36:43 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-14 03:10:28 +0300 |
commit | 3be3f61d25e04ecf90d65d52fad632af5ba8805b (patch) | |
tree | e74b43ccd63d1d063f01281903b7639d226f3bf1 /kernel/kexec_file.c | |
parent | 8da0b724959ccd3f8435214ebdaf1aef548967bb (diff) | |
download | linux-3be3f61d25e04ecf90d65d52fad632af5ba8805b.tar.xz |
kernel/kexec_file.c: allow archs to set purgatory load address
For s390 new kernels are loaded to fixed addresses in memory before they
are booted. With the current code this is a problem as it assumes the
kernel will be loaded to an 'arbitrary' address. In particular,
kexec_locate_mem_hole searches for a large enough memory region and sets
the load address (kexec_bufer->mem) to it.
Luckily there is a simple workaround for this problem. By returning 1
in arch_kexec_walk_mem, kexec_locate_mem_hole is turned off. This
allows the architecture to set kbuf->mem by hand. While the trick works
fine for the kernel it does not for the purgatory as here the
architectures don't have access to its kexec_buffer.
Give architectures access to the purgatories kexec_buffer by changing
kexec_load_purgatory to take a pointer to it. With this change
architectures have access to the buffer and can edit it as they need.
A nice side effect of this change is that we can get rid of the
purgatory_info->purgatory_load_address field. As now the information
stored there can directly be accessed from kbuf->mem.
Link: http://lkml.kernel.org/r/20180321112751.22196-11-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/kexec_file.c')
-rw-r--r-- | kernel/kexec_file.c | 29 |
1 files changed, 16 insertions, 13 deletions
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 269116fd932c..75d8e7cf040e 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -730,8 +730,8 @@ static int kexec_purgatory_setup_kbuf(struct purgatory_info *pi, int i, ret; sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff; - bss_align = 1; - bss_sz = 0; + kbuf->buf_align = bss_align = 1; + kbuf->bufsz = bss_sz = 0; for (i = 0; i < pi->ehdr->e_shnum; i++) { if (!(sechdrs[i].sh_flags & SHF_ALLOC)) @@ -763,7 +763,6 @@ static int kexec_purgatory_setup_kbuf(struct purgatory_info *pi, ret = kexec_add_buffer(kbuf); if (ret) goto out; - pi->purgatory_load_addr = kbuf->mem; return 0; out: @@ -901,27 +900,32 @@ static int kexec_apply_relocations(struct kimage *image) return 0; } -/* Load relocatable purgatory object and relocate it appropriately */ -int kexec_load_purgatory(struct kimage *image, unsigned long min, - unsigned long max, int top_down, - unsigned long *load_addr) +/* + * kexec_load_purgatory - Load and relocate the purgatory object. + * @image: Image to add the purgatory to. + * @kbuf: Memory parameters to use. + * + * Allocates the memory needed for image->purgatory_info.sechdrs and + * image->purgatory_info.purgatory_buf/kbuf->buffer. Caller is responsible + * to free the memory after use. + * + * Return: 0 on success, negative errno on error. + */ +int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf) { struct purgatory_info *pi = &image->purgatory_info; int ret; - struct kexec_buf kbuf = { .image = image, .bufsz = 0, .buf_align = 1, - .buf_min = min, .buf_max = max, - .top_down = top_down }; if (kexec_purgatory_size <= 0) return -EINVAL; pi->ehdr = (const Elf_Ehdr *)kexec_purgatory; - ret = kexec_purgatory_setup_kbuf(pi, &kbuf); + ret = kexec_purgatory_setup_kbuf(pi, kbuf); if (ret) return ret; - ret = kexec_purgatory_setup_sechdrs(pi, &kbuf); + ret = kexec_purgatory_setup_sechdrs(pi, kbuf); if (ret) goto out_free_kbuf; @@ -929,7 +933,6 @@ int kexec_load_purgatory(struct kimage *image, unsigned long min, if (ret) goto out; - *load_addr = pi->purgatory_load_addr; return 0; out: vfree(pi->sechdrs); |