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

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

[Thiago Jung Bauermann]

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 <bauerman@linux.ibm.com>
---
 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;

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

[Dave Young]

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 <bauerman@linux.ibm.com>
> ---
>  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
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec

Reviewed-by: Dave Young <dyoung@redhat.com>

Thanks
Dave

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

[Thiago Jung Bauermann]

Dave Young <dyoung@redhat.com> 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 <bauerman@linux.ibm.com>
>> ---
>>  arch/powerpc/kernel/kexec_elf_64.c | 6 +++++-
>>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> Reviewed-by: Dave Young <dyoung@redhat.com>

Thanks!

-- 
Thiago Jung Bauermann
IBM Linux Technology Center

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

[Michael Ellerman]

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 <bauerman@linux.ibm.com>
> Reviewed-by: Dave Young <dyoung@redhat.com>

Applied to powerpc fixes, thanks.

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

cheers

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

[Thiago Jung Bauermann]

Michael Ellerman <patch-notifications@ellerman.id.au> 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 <bauerman@linux.ibm.com>
>> Reviewed-by: Dave Young <dyoung@redhat.com>
>
> Applied to powerpc fixes, thanks.
>
> https://git.kernel.org/powerpc/c/8b909e3548706cbebc0a676067b81aad

Thanks!!

-- 
Thiago Jung Bauermann
IBM Linux Technology Center