2018-03-29 19:08:04

by Thiago Jung Bauermann

[permalink] [raw]
Subject: [PATCH] powerpc: kexec_file: Fix error code when trying to load kdump kernel

kexec_file_load() on powerpc doesn't support kdump kernels yet, so it
returns -ENOTSUPP in that case.

I've recently learned that this errno is internal to the kernel and isn't
supposed to be exposed to userspace. Therefore, change to -EOPNOTSUPP which
is defined in an uapi header.

This does indeed make kexec-tools happier. Before the patch, on ppc64le:

# ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
kexec_file_load failed: Unknown error 524

After the patch:

# ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
kexec_file_load failed: Operation not supported

Fixes: a0458284f062 ("powerpc: Add support code for kexec_file_load()")
Reported-by: Dave Young <[email protected]>
Signed-off-by: Thiago Jung Bauermann <[email protected]>
---
arch/powerpc/kernel/machine_kexec_file_64.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

This is a minor issue, but since it's a simple patch it might be worth
applying it to stable branches.

This is the kexec-tools thread where this problem was brought up:

https://lists.infradead.org/pipermail/kexec/2018-March/020346.html

And this is an instance of a similar fix being applied elsewhere in the
kernel, for the same reasons:

https://patchwork.kernel.org/patch/8490791/

The test shown in the commit log was made using Hari Bathini's patch
adding kexec_file_load() support to kexec-tools in ppc64.

diff --git a/arch/powerpc/kernel/machine_kexec_file_64.c b/arch/powerpc/kernel/machine_kexec_file_64.c
index e4395f937d63..45e0b7d5f200 100644
--- a/arch/powerpc/kernel/machine_kexec_file_64.c
+++ b/arch/powerpc/kernel/machine_kexec_file_64.c
@@ -43,7 +43,7 @@ int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,

/* We don't support crash kernels yet. */
if (image->type == KEXEC_TYPE_CRASH)
- return -ENOTSUPP;
+ return -EOPNOTSUPP;

for (i = 0; i < ARRAY_SIZE(kexec_file_loaders); i++) {
fops = kexec_file_loaders[i];



2018-03-30 06:29:20

by Simon Horman

[permalink] [raw]
Subject: Re: [PATCH] powerpc: kexec_file: Fix error code when trying to load kdump kernel

On Thu, Mar 29, 2018 at 04:05:43PM -0300, Thiago Jung Bauermann wrote:
> kexec_file_load() on powerpc doesn't support kdump kernels yet, so it
> returns -ENOTSUPP in that case.
>
> I've recently learned that this errno is internal to the kernel and isn't
> supposed to be exposed to userspace. Therefore, change to -EOPNOTSUPP which
> is defined in an uapi header.
>
> This does indeed make kexec-tools happier. Before the patch, on ppc64le:
>
> # ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
> kexec_file_load failed: Unknown error 524
>
> After the patch:
>
> # ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
> kexec_file_load failed: Operation not supported
>
> Fixes: a0458284f062 ("powerpc: Add support code for kexec_file_load()")
> Reported-by: Dave Young <[email protected]>
> Signed-off-by: Thiago Jung Bauermann <[email protected]>

Reviewed-by: Simon Horman <[email protected]>

2018-03-30 08:04:16

by Dave Young

[permalink] [raw]
Subject: Re: [PATCH] powerpc: kexec_file: Fix error code when trying to load kdump kernel

On 03/29/18 at 04:05pm, Thiago Jung Bauermann wrote:
> kexec_file_load() on powerpc doesn't support kdump kernels yet, so it
> returns -ENOTSUPP in that case.
>
> I've recently learned that this errno is internal to the kernel and isn't
> supposed to be exposed to userspace. Therefore, change to -EOPNOTSUPP which
> is defined in an uapi header.
>
> This does indeed make kexec-tools happier. Before the patch, on ppc64le:
>
> # ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
> kexec_file_load failed: Unknown error 524
>
> After the patch:
>
> # ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
> kexec_file_load failed: Operation not supported
>
> Fixes: a0458284f062 ("powerpc: Add support code for kexec_file_load()")
> Reported-by: Dave Young <[email protected]>
> Signed-off-by: Thiago Jung Bauermann <[email protected]>
> ---
> arch/powerpc/kernel/machine_kexec_file_64.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> This is a minor issue, but since it's a simple patch it might be worth
> applying it to stable branches.
>
> This is the kexec-tools thread where this problem was brought up:
>
> https://lists.infradead.org/pipermail/kexec/2018-March/020346.html
>
> And this is an instance of a similar fix being applied elsewhere in the
> kernel, for the same reasons:
>
> https://patchwork.kernel.org/patch/8490791/
>
> The test shown in the commit log was made using Hari Bathini's patch
> adding kexec_file_load() support to kexec-tools in ppc64.
>
> diff --git a/arch/powerpc/kernel/machine_kexec_file_64.c b/arch/powerpc/kernel/machine_kexec_file_64.c
> index e4395f937d63..45e0b7d5f200 100644
> --- a/arch/powerpc/kernel/machine_kexec_file_64.c
> +++ b/arch/powerpc/kernel/machine_kexec_file_64.c
> @@ -43,7 +43,7 @@ int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
>
> /* We don't support crash kernels yet. */
> if (image->type == KEXEC_TYPE_CRASH)
> - return -ENOTSUPP;
> + return -EOPNOTSUPP;
>
> for (i = 0; i < ARRAY_SIZE(kexec_file_loaders); i++) {
> fops = kexec_file_loaders[i];
>
>
> _______________________________________________
> kexec mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/kexec

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

Thanks
Dave


2018-03-31 14:06:22

by Michael Ellerman

[permalink] [raw]
Subject: Re: powerpc: kexec_file: Fix error code when trying to load kdump kernel

On Thu, 2018-03-29 at 19:05:43 UTC, Thiago Jung Bauermann wrote:
> kexec_file_load() on powerpc doesn't support kdump kernels yet, so it
> returns -ENOTSUPP in that case.
>
> I've recently learned that this errno is internal to the kernel and isn't
> supposed to be exposed to userspace. Therefore, change to -EOPNOTSUPP which
> is defined in an uapi header.
>
> This does indeed make kexec-tools happier. Before the patch, on ppc64le:
>
> # ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
> kexec_file_load failed: Unknown error 524
>
> After the patch:
>
> # ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
> kexec_file_load failed: Operation not supported
>
> Fixes: a0458284f062 ("powerpc: Add support code for kexec_file_load()")
> Reported-by: Dave Young <[email protected]>
> Signed-off-by: Thiago Jung Bauermann <[email protected]>
> Reviewed-by: Simon Horman <[email protected]>
> Reviewed-by: Dave Young <[email protected]>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/bf8a1abc3ddbd6e9a8312ea7d96e5d

cheers