2019-05-22 22:05:24

by Thiago Jung Bauermann

[permalink] [raw]
Subject: [PATCH] powerpc: Fix loading of kernel + initramfs with kexec_file_load()

Commit b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
changed kexec_add_buffer() to skip searching for a memory location if
kexec_buf.mem is already set, and use the address that is there.

In powerpc code we reuse a kexec_buf variable for loading both the kernel
and the initramfs by resetting some of the fields between those uses, but
not mem. This causes kexec_add_buffer() to try to load the kernel at the
same address where initramfs will be loaded, which is naturally rejected:

# kexec -s -l --initrd initramfs vmlinuz
kexec_file_load failed: Invalid argument

Setting the mem field before every call to kexec_add_buffer() fixes this
regression.

Fixes: b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
Signed-off-by: Thiago Jung Bauermann <[email protected]>
---
arch/powerpc/kernel/kexec_elf_64.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/kexec_elf_64.c b/arch/powerpc/kernel/kexec_elf_64.c
index ba4f18a43ee8..52a29fc73730 100644
--- a/arch/powerpc/kernel/kexec_elf_64.c
+++ b/arch/powerpc/kernel/kexec_elf_64.c
@@ -547,6 +547,7 @@ static int elf_exec_load(struct kimage *image, struct elfhdr *ehdr,
kbuf.memsz = phdr->p_memsz;
kbuf.buf_align = phdr->p_align;
kbuf.buf_min = phdr->p_paddr + base;
+ kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
ret = kexec_add_buffer(&kbuf);
if (ret)
goto out;
@@ -581,7 +582,8 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
struct kexec_buf kbuf = { .image = image, .buf_min = 0,
.buf_max = ppc64_rma_size };
struct kexec_buf pbuf = { .image = image, .buf_min = 0,
- .buf_max = ppc64_rma_size, .top_down = true };
+ .buf_max = ppc64_rma_size, .top_down = true,
+ .mem = KEXEC_BUF_MEM_UNKNOWN };

ret = build_elf_exec_info(kernel_buf, kernel_len, &ehdr, &elf_info);
if (ret)
@@ -606,6 +608,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
kbuf.bufsz = kbuf.memsz = initrd_len;
kbuf.buf_align = PAGE_SIZE;
kbuf.top_down = false;
+ kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
ret = kexec_add_buffer(&kbuf);
if (ret)
goto out;
@@ -638,6 +641,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
kbuf.bufsz = kbuf.memsz = fdt_size;
kbuf.buf_align = PAGE_SIZE;
kbuf.top_down = true;
+ kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
ret = kexec_add_buffer(&kbuf);
if (ret)
goto out;


2019-05-23 03:24:52

by Dave Young

[permalink] [raw]
Subject: Re: [PATCH] powerpc: Fix loading of kernel + initramfs with kexec_file_load()

On 05/22/19 at 07:01pm, Thiago Jung Bauermann wrote:
> Commit b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
> changed kexec_add_buffer() to skip searching for a memory location if
> kexec_buf.mem is already set, and use the address that is there.
>
> In powerpc code we reuse a kexec_buf variable for loading both the kernel
> and the initramfs by resetting some of the fields between those uses, but
> not mem. This causes kexec_add_buffer() to try to load the kernel at the
> same address where initramfs will be loaded, which is naturally rejected:
>
> # kexec -s -l --initrd initramfs vmlinuz
> kexec_file_load failed: Invalid argument
>
> Setting the mem field before every call to kexec_add_buffer() fixes this
> regression.
>
> Fixes: b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
> Signed-off-by: Thiago Jung Bauermann <[email protected]>
> ---
> arch/powerpc/kernel/kexec_elf_64.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/kernel/kexec_elf_64.c b/arch/powerpc/kernel/kexec_elf_64.c
> index ba4f18a43ee8..52a29fc73730 100644
> --- a/arch/powerpc/kernel/kexec_elf_64.c
> +++ b/arch/powerpc/kernel/kexec_elf_64.c
> @@ -547,6 +547,7 @@ static int elf_exec_load(struct kimage *image, struct elfhdr *ehdr,
> kbuf.memsz = phdr->p_memsz;
> kbuf.buf_align = phdr->p_align;
> kbuf.buf_min = phdr->p_paddr + base;
> + kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
> ret = kexec_add_buffer(&kbuf);
> if (ret)
> goto out;
> @@ -581,7 +582,8 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
> struct kexec_buf kbuf = { .image = image, .buf_min = 0,
> .buf_max = ppc64_rma_size };
> struct kexec_buf pbuf = { .image = image, .buf_min = 0,
> - .buf_max = ppc64_rma_size, .top_down = true };
> + .buf_max = ppc64_rma_size, .top_down = true,
> + .mem = KEXEC_BUF_MEM_UNKNOWN };
>
> ret = build_elf_exec_info(kernel_buf, kernel_len, &ehdr, &elf_info);
> if (ret)
> @@ -606,6 +608,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
> kbuf.bufsz = kbuf.memsz = initrd_len;
> kbuf.buf_align = PAGE_SIZE;
> kbuf.top_down = false;
> + kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
> ret = kexec_add_buffer(&kbuf);
> if (ret)
> goto out;
> @@ -638,6 +641,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
> kbuf.bufsz = kbuf.memsz = fdt_size;
> kbuf.buf_align = PAGE_SIZE;
> kbuf.top_down = true;
> + kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
> ret = kexec_add_buffer(&kbuf);
> if (ret)
> goto out;
>
>
> _______________________________________________
> kexec mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/kexec

Reviewed-by: Dave Young <[email protected]>

Thanks
Dave

2019-05-23 04:46:55

by Thiago Jung Bauermann

[permalink] [raw]
Subject: Re: [PATCH] powerpc: Fix loading of kernel + initramfs with kexec_file_load()


Dave Young <[email protected]> writes:

> On 05/22/19 at 07:01pm, Thiago Jung Bauermann wrote:
>> Commit b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
>> changed kexec_add_buffer() to skip searching for a memory location if
>> kexec_buf.mem is already set, and use the address that is there.
>>
>> In powerpc code we reuse a kexec_buf variable for loading both the kernel
>> and the initramfs by resetting some of the fields between those uses, but
>> not mem. This causes kexec_add_buffer() to try to load the kernel at the
>> same address where initramfs will be loaded, which is naturally rejected:
>>
>> # kexec -s -l --initrd initramfs vmlinuz
>> kexec_file_load failed: Invalid argument
>>
>> Setting the mem field before every call to kexec_add_buffer() fixes this
>> regression.
>>
>> Fixes: b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
>> Signed-off-by: Thiago Jung Bauermann <[email protected]>
>> ---
>> arch/powerpc/kernel/kexec_elf_64.c | 6 +++++-
>> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> Reviewed-by: Dave Young <[email protected]>

Thanks!

--
Thiago Jung Bauermann
IBM Linux Technology Center

2019-05-25 00:58:35

by Michael Ellerman

[permalink] [raw]
Subject: Re: [PATCH] powerpc: Fix loading of kernel + initramfs with kexec_file_load()

On Wed, 2019-05-22 at 22:01:58 UTC, Thiago Jung Bauermann wrote:
> Commit b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
> changed kexec_add_buffer() to skip searching for a memory location if
> kexec_buf.mem is already set, and use the address that is there.
>
> In powerpc code we reuse a kexec_buf variable for loading both the kernel
> and the initramfs by resetting some of the fields between those uses, but
> not mem. This causes kexec_add_buffer() to try to load the kernel at the
> same address where initramfs will be loaded, which is naturally rejected:
>
> # kexec -s -l --initrd initramfs vmlinuz
> kexec_file_load failed: Invalid argument
>
> Setting the mem field before every call to kexec_add_buffer() fixes this
> regression.
>
> Fixes: b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
> Signed-off-by: Thiago Jung Bauermann <[email protected]>
> Reviewed-by: Dave Young <[email protected]>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/8b909e3548706cbebc0a676067b81aad

cheers

2019-05-27 20:16:20

by Thiago Jung Bauermann

[permalink] [raw]
Subject: Re: [PATCH] powerpc: Fix loading of kernel + initramfs with kexec_file_load()


Michael Ellerman <[email protected]> writes:

> On Wed, 2019-05-22 at 22:01:58 UTC, Thiago Jung Bauermann wrote:
>> Commit b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
>> changed kexec_add_buffer() to skip searching for a memory location if
>> kexec_buf.mem is already set, and use the address that is there.
>>
>> In powerpc code we reuse a kexec_buf variable for loading both the kernel
>> and the initramfs by resetting some of the fields between those uses, but
>> not mem. This causes kexec_add_buffer() to try to load the kernel at the
>> same address where initramfs will be loaded, which is naturally rejected:
>>
>> # kexec -s -l --initrd initramfs vmlinuz
>> kexec_file_load failed: Invalid argument
>>
>> Setting the mem field before every call to kexec_add_buffer() fixes this
>> regression.
>>
>> Fixes: b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
>> Signed-off-by: Thiago Jung Bauermann <[email protected]>
>> Reviewed-by: Dave Young <[email protected]>
>
> Applied to powerpc fixes, thanks.
>
> https://git.kernel.org/powerpc/c/8b909e3548706cbebc0a676067b81aad

Thanks!!

--
Thiago Jung Bauermann
IBM Linux Technology Center