| Message ID | 20180222111732.23051-4-takahiro.akashi@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | arm64: kexec: add kexec_file_load() support | expand |
Hi AKASHI, On 02/22/18 at 08:17pm, AKASHI Takahiro wrote: > As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup() > and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops > array and now duplicated among some architectures, let's factor them out. > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > Cc: Dave Young <dyoung@redhat.com> > Cc: Vivek Goyal <vgoyal@redhat.com> > Cc: Baoquan He <bhe@redhat.com> > Cc: Michael Ellerman <mpe@ellerman.id.au> > Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> > --- > arch/powerpc/include/asm/kexec.h | 2 +- > arch/powerpc/kernel/kexec_elf_64.c | 2 +- > arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------ > arch/x86/include/asm/kexec-bzimage64.h | 2 +- > arch/x86/kernel/kexec-bzimage64.c | 2 +- > arch/x86/kernel/machine_kexec_64.c | 45 +---------------------- > include/linux/kexec.h | 15 ++++---- > kernel/kexec_file.c | 57 +++++++++++++++++++++++++++-- > 8 files changed, 70 insertions(+), 94 deletions(-) > [snip] > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > index 990adae52151..a6d14a768b3e 100644 > --- a/kernel/kexec_file.c > +++ b/kernel/kexec_file.c > @@ -26,34 +26,83 @@ > #include <linux/vmalloc.h> > #include "kexec_internal.h" > > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; > + > #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY > static int kexec_calculate_store_digests(struct kimage *image); > #else > static int kexec_calculate_store_digests(struct kimage *image) { return 0; }; > #endif > > +int _kexec_kernel_image_probe(struct kimage *image, void *buf, > + unsigned long buf_len) > +{ > + const struct kexec_file_ops * const *fops; > + int ret = -ENOEXEC; > + > + for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { > + ret = (*fops)->probe(buf, buf_len); > + if (!ret) { > + image->fops = *fops; > + return ret; > + } > + } > + > + return ret; > +} > + > /* Architectures can provide this probe function */ > int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, > unsigned long buf_len) > { > - return -ENOEXEC; > + return _kexec_kernel_image_probe(image, buf, buf_len); I vaguely remember previously I suggest split the _kexec_kernel_image_probe because arch code can call them, and common code also use it like above. But in your new series I do not find where else calls this function except the common code arch_kexec_kernel_image_probe. If nobody use them then it is not worth to split them out, it is better to just embed them in the __weak functions. Ditto for other similar functions. [snip] Thanks Dave
On Fri, Feb 23, 2018 at 05:24:59PM +0800, Dave Young wrote: > Hi AKASHI, > > On 02/22/18 at 08:17pm, AKASHI Takahiro wrote: > > As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup() > > and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops > > array and now duplicated among some architectures, let's factor them out. > > > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > > Cc: Dave Young <dyoung@redhat.com> > > Cc: Vivek Goyal <vgoyal@redhat.com> > > Cc: Baoquan He <bhe@redhat.com> > > Cc: Michael Ellerman <mpe@ellerman.id.au> > > Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> > > --- > > arch/powerpc/include/asm/kexec.h | 2 +- > > arch/powerpc/kernel/kexec_elf_64.c | 2 +- > > arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------ > > arch/x86/include/asm/kexec-bzimage64.h | 2 +- > > arch/x86/kernel/kexec-bzimage64.c | 2 +- > > arch/x86/kernel/machine_kexec_64.c | 45 +---------------------- > > include/linux/kexec.h | 15 ++++---- > > kernel/kexec_file.c | 57 +++++++++++++++++++++++++++-- > > 8 files changed, 70 insertions(+), 94 deletions(-) > > > > [snip] > > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > > index 990adae52151..a6d14a768b3e 100644 > > --- a/kernel/kexec_file.c > > +++ b/kernel/kexec_file.c > > @@ -26,34 +26,83 @@ > > #include <linux/vmalloc.h> > > #include "kexec_internal.h" > > > > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; > > + > > #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY > > static int kexec_calculate_store_digests(struct kimage *image); > > #else > > static int kexec_calculate_store_digests(struct kimage *image) { return 0; }; > > #endif > > > > +int _kexec_kernel_image_probe(struct kimage *image, void *buf, > > + unsigned long buf_len) > > +{ > > + const struct kexec_file_ops * const *fops; > > + int ret = -ENOEXEC; > > + > > + for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { > > + ret = (*fops)->probe(buf, buf_len); > > + if (!ret) { > > + image->fops = *fops; > > + return ret; > > + } > > + } > > + > > + return ret; > > +} > > + > > /* Architectures can provide this probe function */ > > int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, > > unsigned long buf_len) > > { > > - return -ENOEXEC; > > + return _kexec_kernel_image_probe(image, buf, buf_len); > > > I vaguely remember previously I suggest split the _kexec_kernel_image_probe > because arch code can call them, and common code also use it like above. > But in your new series I do not find where else calls this function > except the common code arch_kexec_kernel_image_probe. If nobody use > them then it is not worth to split them out, it is better to just embed > them in the __weak functions. Powerpc's arch_kexec_kernel_image_probe() uses _kexec_kekrnel_image_probe() as it needs an extra check to rule out crash dump for now. Thanks, -Takahiro AKASHI > Ditto for other similar functions. > > [snip] > > Thanks > Dave
Hi AKASHI On Thu, 22 Feb 2018 20:17:22 +0900 AKASHI Takahiro <takahiro.akashi@linaro.org> wrote: [...] > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > index 990adae52151..a6d14a768b3e 100644 > --- a/kernel/kexec_file.c > +++ b/kernel/kexec_file.c > @@ -26,34 +26,83 @@ > #include <linux/vmalloc.h> > #include "kexec_internal.h" > > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; > + Having a weak definition of kexec_file_loaders causes trouble on s390 with gcc 4.8 (newer versions seem to work fine). For me it looks like that in this version gcc doesn't recognize __weak but use the default value for optimization. This leads to _kexec_kernel_image_probe to always return ENOEXEC because the for-loop gets optimized out. The problem can easily be worked around by declaring kexec_file_loaders in include/linux/kexec.h and defining it in arch code. In particular doing this diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 37e9dce518aa..fc0788540d90 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -139,6 +139,8 @@ struct kexec_file_ops { #endif }; +extern const struct kexec_file_ops * const kexec_file_loaders[]; + /** * struct kexec_buf - parameters for finding a place for a buffer in memory * @image: kexec image in which memory to search. diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 17ba407d0e79..4e3d1e4bc7f6 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -31,8 +31,6 @@ #include <linux/vmalloc.h> #include "kexec_internal.h" -const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; - #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY static int kexec_calculate_store_digests(struct kimage *image); #else A nice side effect of this solution is, that a developer who forgets to define kexec_file_loaders gets a linker error. So he directly knows what's missing instead of first having to find out where/why an error gets returned. Otherwise the series is fine for me. Thanks Philipp > #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY > static int kexec_calculate_store_digests(struct kimage *image); > #else > static int kexec_calculate_store_digests(struct kimage *image) { return 0; }; > #endif > > +int _kexec_kernel_image_probe(struct kimage *image, void *buf, > + unsigned long buf_len) > +{ > + const struct kexec_file_ops * const *fops; > + int ret = -ENOEXEC; > + > + for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { > + ret = (*fops)->probe(buf, buf_len); > + if (!ret) { > + image->fops = *fops; > + return ret; > + } > + } > + > + return ret; > +} > + > /* Architectures can provide this probe function */ > int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, > unsigned long buf_len) > { > - return -ENOEXEC; > + return _kexec_kernel_image_probe(image, buf, buf_len); > +} > + > +void *_kexec_kernel_image_load(struct kimage *image) > +{ > + if (!image->fops || !image->fops->load) > + return ERR_PTR(-ENOEXEC); > + > + return image->fops->load(image, image->kernel_buf, > + image->kernel_buf_len, image->initrd_buf, > + image->initrd_buf_len, image->cmdline_buf, > + image->cmdline_buf_len); > } > > void * __weak arch_kexec_kernel_image_load(struct kimage *image) > { > - return ERR_PTR(-ENOEXEC); > + return _kexec_kernel_image_load(image); > +} > + > +int _kimage_file_post_load_cleanup(struct kimage *image) > +{ > + if (!image->fops || !image->fops->cleanup) > + return 0; > + > + return image->fops->cleanup(image->image_loader_data); > } > > int __weak arch_kimage_file_post_load_cleanup(struct kimage *image) > { > - return -EINVAL; > + return _kimage_file_post_load_cleanup(image); > } > > #ifdef CONFIG_KEXEC_VERIFY_SIG > +int _kexec_kernel_verify_sig(struct kimage *image, void *buf, > + unsigned long buf_len) > +{ > + if (!image->fops || !image->fops->verify_sig) { > + pr_debug("kernel loader does not support signature verification.\n"); > + return -EKEYREJECTED; > + } > + > + return image->fops->verify_sig(buf, buf_len); > +} > + > int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, > unsigned long buf_len) > { > - return -EKEYREJECTED; > + return _kexec_kernel_verify_sig(image, buf, buf_len); > } > #endif >
On Mon, 26 Feb 2018 19:01:39 +0900 AKASHI Takahiro <takahiro.akashi@linaro.org> wrote: > On Fri, Feb 23, 2018 at 05:24:59PM +0800, Dave Young wrote: > > Hi AKASHI, > > > > On 02/22/18 at 08:17pm, AKASHI Takahiro wrote: > > > As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup() > > > and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops > > > array and now duplicated among some architectures, let's factor them out. > > > > > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > > > Cc: Dave Young <dyoung@redhat.com> > > > Cc: Vivek Goyal <vgoyal@redhat.com> > > > Cc: Baoquan He <bhe@redhat.com> > > > Cc: Michael Ellerman <mpe@ellerman.id.au> > > > Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> > > > --- > > > arch/powerpc/include/asm/kexec.h | 2 +- > > > arch/powerpc/kernel/kexec_elf_64.c | 2 +- > > > arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------ > > > arch/x86/include/asm/kexec-bzimage64.h | 2 +- > > > arch/x86/kernel/kexec-bzimage64.c | 2 +- > > > arch/x86/kernel/machine_kexec_64.c | 45 +---------------------- > > > include/linux/kexec.h | 15 ++++---- > > > kernel/kexec_file.c | 57 +++++++++++++++++++++++++++-- > > > 8 files changed, 70 insertions(+), 94 deletions(-) > > > > > > > [snip] > > > > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > > > index 990adae52151..a6d14a768b3e 100644 > > > --- a/kernel/kexec_file.c > > > +++ b/kernel/kexec_file.c > > > @@ -26,34 +26,83 @@ > > > #include <linux/vmalloc.h> > > > #include "kexec_internal.h" > > > > > > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; > > > + > > > #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY > > > static int kexec_calculate_store_digests(struct kimage *image); > > > #else > > > static int kexec_calculate_store_digests(struct kimage *image) { return 0; }; > > > #endif > > > > > > +int _kexec_kernel_image_probe(struct kimage *image, void *buf, > > > + unsigned long buf_len) > > > +{ > > > + const struct kexec_file_ops * const *fops; > > > + int ret = -ENOEXEC; > > > + > > > + for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { > > > + ret = (*fops)->probe(buf, buf_len); > > > + if (!ret) { > > > + image->fops = *fops; > > > + return ret; > > > + } > > > + } > > > + > > > + return ret; > > > +} > > > + > > > /* Architectures can provide this probe function */ > > > int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, > > > unsigned long buf_len) > > > { > > > - return -ENOEXEC; > > > + return _kexec_kernel_image_probe(image, buf, buf_len); > > > > > > I vaguely remember previously I suggest split the _kexec_kernel_image_probe > > because arch code can call them, and common code also use it like above. > > But in your new series I do not find where else calls this function > > except the common code arch_kexec_kernel_image_probe. If nobody use > > them then it is not worth to split them out, it is better to just embed > > them in the __weak functions. > > Powerpc's arch_kexec_kernel_image_probe() uses > _kexec_kekrnel_image_probe() as it needs an extra check to rule out > crash dump for now. s390 has to use it too. We have to write to a fixed address in the buffer. So we need to check if the buffer is large enough to write to that address. Philipp > Thanks, > -Takahiro AKASHI > > > > Ditto for other similar functions. > > > > [snip] > > > > Thanks > > Dave > > _______________________________________________ > kexec mailing list > kexec@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/kexec >
On Mon, Feb 26, 2018 at 12:17:18PM +0100, Philipp Rudo wrote: > Hi AKASHI > > On Thu, 22 Feb 2018 20:17:22 +0900 > AKASHI Takahiro <takahiro.akashi@linaro.org> wrote: > > [...] > > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > > index 990adae52151..a6d14a768b3e 100644 > > --- a/kernel/kexec_file.c > > +++ b/kernel/kexec_file.c > > @@ -26,34 +26,83 @@ > > #include <linux/vmalloc.h> > > #include "kexec_internal.h" > > > > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; > > + > > Having a weak definition of kexec_file_loaders causes trouble on s390 with > gcc 4.8 (newer versions seem to work fine). For me it looks like that in this > version gcc doesn't recognize __weak but use the default value for > optimization. This leads to _kexec_kernel_image_probe to always return ENOEXEC > because the for-loop gets optimized out. I gave it a try to compile with gcc 4.9 (not 4.8) for arm64 and didn't see any errors or warnings, but > The problem can easily be worked around by declaring kexec_file_loaders in > include/linux/kexec.h and defining it in arch code. In particular doing this > > diff --git a/include/linux/kexec.h b/include/linux/kexec.h > index 37e9dce518aa..fc0788540d90 100644 > --- a/include/linux/kexec.h > +++ b/include/linux/kexec.h > @@ -139,6 +139,8 @@ struct kexec_file_ops { > #endif > }; > > +extern const struct kexec_file_ops * const kexec_file_loaders[]; > + > /** > * struct kexec_buf - parameters for finding a place for a buffer in memory > * @image: kexec image in which memory to search. > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > index 17ba407d0e79..4e3d1e4bc7f6 100644 > --- a/kernel/kexec_file.c > +++ b/kernel/kexec_file.c > @@ -31,8 +31,6 @@ > #include <linux/vmalloc.h> > #include "kexec_internal.h" > > -const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; > - > #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY > static int kexec_calculate_store_digests(struct kimage *image); > #else Your change is just fine with me, too. I will incorporate it in my next version. Thanks, -Takahiro AKASHI > A nice side effect of this solution is, that a developer who forgets to define > kexec_file_loaders gets a linker error. So he directly knows what's missing > instead of first having to find out where/why an error gets returned. > > Otherwise the series is fine for me. > > Thanks > Philipp > > > #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY > > static int kexec_calculate_store_digests(struct kimage *image); > > #else > > static int kexec_calculate_store_digests(struct kimage *image) { return 0; }; > > #endif > > > > +int _kexec_kernel_image_probe(struct kimage *image, void *buf, > > + unsigned long buf_len) > > +{ > > + const struct kexec_file_ops * const *fops; > > + int ret = -ENOEXEC; > > + > > + for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { > > + ret = (*fops)->probe(buf, buf_len); > > + if (!ret) { > > + image->fops = *fops; > > + return ret; > > + } > > + } > > + > > + return ret; > > +} > > + > > /* Architectures can provide this probe function */ > > int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, > > unsigned long buf_len) > > { > > - return -ENOEXEC; > > + return _kexec_kernel_image_probe(image, buf, buf_len); > > +} > > + > > +void *_kexec_kernel_image_load(struct kimage *image) > > +{ > > + if (!image->fops || !image->fops->load) > > + return ERR_PTR(-ENOEXEC); > > + > > + return image->fops->load(image, image->kernel_buf, > > + image->kernel_buf_len, image->initrd_buf, > > + image->initrd_buf_len, image->cmdline_buf, > > + image->cmdline_buf_len); > > } > > > > void * __weak arch_kexec_kernel_image_load(struct kimage *image) > > { > > - return ERR_PTR(-ENOEXEC); > > + return _kexec_kernel_image_load(image); > > +} > > + > > +int _kimage_file_post_load_cleanup(struct kimage *image) > > +{ > > + if (!image->fops || !image->fops->cleanup) > > + return 0; > > + > > + return image->fops->cleanup(image->image_loader_data); > > } > > > > int __weak arch_kimage_file_post_load_cleanup(struct kimage *image) > > { > > - return -EINVAL; > > + return _kimage_file_post_load_cleanup(image); > > } > > > > #ifdef CONFIG_KEXEC_VERIFY_SIG > > +int _kexec_kernel_verify_sig(struct kimage *image, void *buf, > > + unsigned long buf_len) > > +{ > > + if (!image->fops || !image->fops->verify_sig) { > > + pr_debug("kernel loader does not support signature verification.\n"); > > + return -EKEYREJECTED; > > + } > > + > > + return image->fops->verify_sig(buf, buf_len); > > +} > > + > > int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, > > unsigned long buf_len) > > { > > - return -EKEYREJECTED; > > + return _kexec_kernel_verify_sig(image, buf, buf_len); > > } > > #endif > > >
On Tue, 27 Feb 2018 11:03:07 +0900 AKASHI Takahiro <takahiro.akashi@linaro.org> wrote: > On Mon, Feb 26, 2018 at 12:17:18PM +0100, Philipp Rudo wrote: > > Hi AKASHI > > > > On Thu, 22 Feb 2018 20:17:22 +0900 > > AKASHI Takahiro <takahiro.akashi@linaro.org> wrote: > > > > [...] > > > > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > > > index 990adae52151..a6d14a768b3e 100644 > > > --- a/kernel/kexec_file.c > > > +++ b/kernel/kexec_file.c > > > @@ -26,34 +26,83 @@ > > > #include <linux/vmalloc.h> > > > #include "kexec_internal.h" > > > > > > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; > > > + > > > > Having a weak definition of kexec_file_loaders causes trouble on s390 with > > gcc 4.8 (newer versions seem to work fine). For me it looks like that in this > > version gcc doesn't recognize __weak but use the default value for > > optimization. This leads to _kexec_kernel_image_probe to always return ENOEXEC > > because the for-loop gets optimized out. > > I gave it a try to compile with gcc 4.9 (not 4.8) for arm64 > and didn't see any errors or warnings, but I talked to our compiler guys, and it looks like its a bug in gcc which was introduced with gcc 4.8 and removed again with gcc 4.9. So I was just extremely lucky hitting the sweat spot... > > The problem can easily be worked around by declaring kexec_file_loaders in > > include/linux/kexec.h and defining it in arch code. In particular doing this > > > > diff --git a/include/linux/kexec.h b/include/linux/kexec.h > > index 37e9dce518aa..fc0788540d90 100644 > > --- a/include/linux/kexec.h > > +++ b/include/linux/kexec.h > > @@ -139,6 +139,8 @@ struct kexec_file_ops { > > #endif > > }; > > > > +extern const struct kexec_file_ops * const kexec_file_loaders[]; > > + > > /** > > * struct kexec_buf - parameters for finding a place for a buffer in memory > > * @image: kexec image in which memory to search. > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > > index 17ba407d0e79..4e3d1e4bc7f6 100644 > > --- a/kernel/kexec_file.c > > +++ b/kernel/kexec_file.c > > @@ -31,8 +31,6 @@ > > #include <linux/vmalloc.h> > > #include "kexec_internal.h" > > > > -const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; > > - > > #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY > > static int kexec_calculate_store_digests(struct kimage *image); > > #else > > Your change is just fine with me, too. > I will incorporate it in my next version. Thanks a lot Philipp > Thanks, > -Takahiro AKASHI > > > A nice side effect of this solution is, that a developer who forgets to define > > kexec_file_loaders gets a linker error. So he directly knows what's missing > > instead of first having to find out where/why an error gets returned. > > > > Otherwise the series is fine for me. > > > > Thanks > > Philipp > > > > > #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY > > > static int kexec_calculate_store_digests(struct kimage *image); > > > #else > > > static int kexec_calculate_store_digests(struct kimage *image) { return 0; }; > > > #endif > > > > > > +int _kexec_kernel_image_probe(struct kimage *image, void *buf, > > > + unsigned long buf_len) > > > +{ > > > + const struct kexec_file_ops * const *fops; > > > + int ret = -ENOEXEC; > > > + > > > + for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { > > > + ret = (*fops)->probe(buf, buf_len); > > > + if (!ret) { > > > + image->fops = *fops; > > > + return ret; > > > + } > > > + } > > > + > > > + return ret; > > > +} > > > + > > > /* Architectures can provide this probe function */ > > > int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, > > > unsigned long buf_len) > > > { > > > - return -ENOEXEC; > > > + return _kexec_kernel_image_probe(image, buf, buf_len); > > > +} > > > + > > > +void *_kexec_kernel_image_load(struct kimage *image) > > > +{ > > > + if (!image->fops || !image->fops->load) > > > + return ERR_PTR(-ENOEXEC); > > > + > > > + return image->fops->load(image, image->kernel_buf, > > > + image->kernel_buf_len, image->initrd_buf, > > > + image->initrd_buf_len, image->cmdline_buf, > > > + image->cmdline_buf_len); > > > } > > > > > > void * __weak arch_kexec_kernel_image_load(struct kimage *image) > > > { > > > - return ERR_PTR(-ENOEXEC); > > > + return _kexec_kernel_image_load(image); > > > +} > > > + > > > +int _kimage_file_post_load_cleanup(struct kimage *image) > > > +{ > > > + if (!image->fops || !image->fops->cleanup) > > > + return 0; > > > + > > > + return image->fops->cleanup(image->image_loader_data); > > > } > > > > > > int __weak arch_kimage_file_post_load_cleanup(struct kimage *image) > > > { > > > - return -EINVAL; > > > + return _kimage_file_post_load_cleanup(image); > > > } > > > > > > #ifdef CONFIG_KEXEC_VERIFY_SIG > > > +int _kexec_kernel_verify_sig(struct kimage *image, void *buf, > > > + unsigned long buf_len) > > > +{ > > > + if (!image->fops || !image->fops->verify_sig) { > > > + pr_debug("kernel loader does not support signature verification.\n"); > > > + return -EKEYREJECTED; > > > + } > > > + > > > + return image->fops->verify_sig(buf, buf_len); > > > +} > > > + > > > int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, > > > unsigned long buf_len) > > > { > > > - return -EKEYREJECTED; > > > + return _kexec_kernel_verify_sig(image, buf, buf_len); > > > } > > > #endif > > > > > >
On 02/26/18 at 07:01pm, AKASHI Takahiro wrote: > On Fri, Feb 23, 2018 at 05:24:59PM +0800, Dave Young wrote: > > Hi AKASHI, > > > > On 02/22/18 at 08:17pm, AKASHI Takahiro wrote: > > > As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup() > > > and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops > > > array and now duplicated among some architectures, let's factor them out. > > > > > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > > > Cc: Dave Young <dyoung@redhat.com> > > > Cc: Vivek Goyal <vgoyal@redhat.com> > > > Cc: Baoquan He <bhe@redhat.com> > > > Cc: Michael Ellerman <mpe@ellerman.id.au> > > > Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> > > > --- > > > arch/powerpc/include/asm/kexec.h | 2 +- > > > arch/powerpc/kernel/kexec_elf_64.c | 2 +- > > > arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------ > > > arch/x86/include/asm/kexec-bzimage64.h | 2 +- > > > arch/x86/kernel/kexec-bzimage64.c | 2 +- > > > arch/x86/kernel/machine_kexec_64.c | 45 +---------------------- > > > include/linux/kexec.h | 15 ++++---- > > > kernel/kexec_file.c | 57 +++++++++++++++++++++++++++-- > > > 8 files changed, 70 insertions(+), 94 deletions(-) > > > > > > > [snip] > > > > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > > > index 990adae52151..a6d14a768b3e 100644 > > > --- a/kernel/kexec_file.c > > > +++ b/kernel/kexec_file.c > > > @@ -26,34 +26,83 @@ > > > #include <linux/vmalloc.h> > > > #include "kexec_internal.h" > > > > > > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; > > > + > > > #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY > > > static int kexec_calculate_store_digests(struct kimage *image); > > > #else > > > static int kexec_calculate_store_digests(struct kimage *image) { return 0; }; > > > #endif > > > > > > +int _kexec_kernel_image_probe(struct kimage *image, void *buf, > > > + unsigned long buf_len) > > > +{ > > > + const struct kexec_file_ops * const *fops; > > > + int ret = -ENOEXEC; > > > + > > > + for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { > > > + ret = (*fops)->probe(buf, buf_len); > > > + if (!ret) { > > > + image->fops = *fops; > > > + return ret; > > > + } > > > + } > > > + > > > + return ret; > > > +} > > > + > > > /* Architectures can provide this probe function */ > > > int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, > > > unsigned long buf_len) > > > { > > > - return -ENOEXEC; > > > + return _kexec_kernel_image_probe(image, buf, buf_len); > > > > > > I vaguely remember previously I suggest split the _kexec_kernel_image_probe > > because arch code can call them, and common code also use it like above. > > But in your new series I do not find where else calls this function > > except the common code arch_kexec_kernel_image_probe. If nobody use > > them then it is not worth to split them out, it is better to just embed > > them in the __weak functions. > > Powerpc's arch_kexec_kernel_image_probe() uses > _kexec_kekrnel_image_probe() as it needs an extra check to rule out > crash dump for now. Oops, I missed that, but what about other similar functions? Such as: _kexec_kernel_image_load _kimage_file_post_load_cleanup _kexec_kernel_verify_sig > > Thanks, > -Takahiro AKASHI > > > > Ditto for other similar functions. > > > > [snip] > > > > Thanks > > Dave Thanks Dave
On Wed, Feb 28, 2018 at 08:38:00PM +0800, Dave Young wrote: > On 02/26/18 at 07:01pm, AKASHI Takahiro wrote: > > On Fri, Feb 23, 2018 at 05:24:59PM +0800, Dave Young wrote: > > > Hi AKASHI, > > > > > > On 02/22/18 at 08:17pm, AKASHI Takahiro wrote: > > > > As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup() > > > > and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops > > > > array and now duplicated among some architectures, let's factor them out. > > > > > > > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > > > > Cc: Dave Young <dyoung@redhat.com> > > > > Cc: Vivek Goyal <vgoyal@redhat.com> > > > > Cc: Baoquan He <bhe@redhat.com> > > > > Cc: Michael Ellerman <mpe@ellerman.id.au> > > > > Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> > > > > --- > > > > arch/powerpc/include/asm/kexec.h | 2 +- > > > > arch/powerpc/kernel/kexec_elf_64.c | 2 +- > > > > arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------ > > > > arch/x86/include/asm/kexec-bzimage64.h | 2 +- > > > > arch/x86/kernel/kexec-bzimage64.c | 2 +- > > > > arch/x86/kernel/machine_kexec_64.c | 45 +---------------------- > > > > include/linux/kexec.h | 15 ++++---- > > > > kernel/kexec_file.c | 57 +++++++++++++++++++++++++++-- > > > > 8 files changed, 70 insertions(+), 94 deletions(-) > > > > > > > > > > [snip] > > > > > > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > > > > index 990adae52151..a6d14a768b3e 100644 > > > > --- a/kernel/kexec_file.c > > > > +++ b/kernel/kexec_file.c > > > > @@ -26,34 +26,83 @@ > > > > #include <linux/vmalloc.h> > > > > #include "kexec_internal.h" > > > > > > > > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; > > > > + > > > > #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY > > > > static int kexec_calculate_store_digests(struct kimage *image); > > > > #else > > > > static int kexec_calculate_store_digests(struct kimage *image) { return 0; }; > > > > #endif > > > > > > > > +int _kexec_kernel_image_probe(struct kimage *image, void *buf, > > > > + unsigned long buf_len) > > > > +{ > > > > + const struct kexec_file_ops * const *fops; > > > > + int ret = -ENOEXEC; > > > > + > > > > + for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { > > > > + ret = (*fops)->probe(buf, buf_len); > > > > + if (!ret) { > > > > + image->fops = *fops; > > > > + return ret; > > > > + } > > > > + } > > > > + > > > > + return ret; > > > > +} > > > > + > > > > /* Architectures can provide this probe function */ > > > > int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, > > > > unsigned long buf_len) > > > > { > > > > - return -ENOEXEC; > > > > + return _kexec_kernel_image_probe(image, buf, buf_len); > > > > > > > > > I vaguely remember previously I suggest split the _kexec_kernel_image_probe > > > because arch code can call them, and common code also use it like above. > > > But in your new series I do not find where else calls this function > > > except the common code arch_kexec_kernel_image_probe. If nobody use > > > them then it is not worth to split them out, it is better to just embed > > > them in the __weak functions. > > > > Powerpc's arch_kexec_kernel_image_probe() uses > > _kexec_kekrnel_image_probe() as it needs an extra check to rule out > > crash dump for now. > > Oops, I missed that, but what about other similar functions? Such as: > _kexec_kernel_image_load > _kimage_file_post_load_cleanup > _kexec_kernel_verify_sig Current no users. Given those functions are so simple, we could go either way. -Takahiro AKASHI > > > > Thanks, > > -Takahiro AKASHI > > > > > > > Ditto for other similar functions. > > > > > > [snip] > > > > > > Thanks > > > Dave > > Thanks > Dave
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h index d8b1e8e7e035..4a585cba1787 100644 --- a/arch/powerpc/include/asm/kexec.h +++ b/arch/powerpc/include/asm/kexec.h @@ -95,7 +95,7 @@ static inline bool kdump_in_progress(void) } #ifdef CONFIG_KEXEC_FILE -extern struct kexec_file_ops kexec_elf64_ops; +extern const struct kexec_file_ops kexec_elf64_ops; #ifdef CONFIG_IMA_KEXEC #define ARCH_HAS_KIMAGE_ARCH diff --git a/arch/powerpc/kernel/kexec_elf_64.c b/arch/powerpc/kernel/kexec_elf_64.c index 9a42309b091a..6c78c11c7faf 100644 --- a/arch/powerpc/kernel/kexec_elf_64.c +++ b/arch/powerpc/kernel/kexec_elf_64.c @@ -657,7 +657,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, return ret ? ERR_PTR(ret) : fdt; } -struct kexec_file_ops kexec_elf64_ops = { +const struct kexec_file_ops kexec_elf64_ops = { .probe = elf64_probe, .load = elf64_load, }; diff --git a/arch/powerpc/kernel/machine_kexec_file_64.c b/arch/powerpc/kernel/machine_kexec_file_64.c index e4395f937d63..a27ec647350c 100644 --- a/arch/powerpc/kernel/machine_kexec_file_64.c +++ b/arch/powerpc/kernel/machine_kexec_file_64.c @@ -31,52 +31,19 @@ #define SLAVE_CODE_SIZE 256 -static struct kexec_file_ops *kexec_file_loaders[] = { +const struct kexec_file_ops * const kexec_file_loaders[] = { &kexec_elf64_ops, + NULL }; int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, unsigned long buf_len) { - int i, ret = -ENOEXEC; - struct kexec_file_ops *fops; - /* We don't support crash kernels yet. */ if (image->type == KEXEC_TYPE_CRASH) return -ENOTSUPP; - for (i = 0; i < ARRAY_SIZE(kexec_file_loaders); i++) { - fops = kexec_file_loaders[i]; - if (!fops || !fops->probe) - continue; - - ret = fops->probe(buf, buf_len); - if (!ret) { - image->fops = fops; - return ret; - } - } - - return ret; -} - -void *arch_kexec_kernel_image_load(struct kimage *image) -{ - if (!image->fops || !image->fops->load) - return ERR_PTR(-ENOEXEC); - - return image->fops->load(image, image->kernel_buf, - image->kernel_buf_len, image->initrd_buf, - image->initrd_buf_len, image->cmdline_buf, - image->cmdline_buf_len); -} - -int arch_kimage_file_post_load_cleanup(struct kimage *image) -{ - if (!image->fops || !image->fops->cleanup) - return 0; - - return image->fops->cleanup(image->image_loader_data); + return _kexec_kernel_image_probe(image, buf, buf_len); } /** diff --git a/arch/x86/include/asm/kexec-bzimage64.h b/arch/x86/include/asm/kexec-bzimage64.h index 9f07cff43705..df89ee7d3e9e 100644 --- a/arch/x86/include/asm/kexec-bzimage64.h +++ b/arch/x86/include/asm/kexec-bzimage64.h @@ -2,6 +2,6 @@ #ifndef _ASM_KEXEC_BZIMAGE64_H #define _ASM_KEXEC_BZIMAGE64_H -extern struct kexec_file_ops kexec_bzImage64_ops; +extern const struct kexec_file_ops kexec_bzImage64_ops; #endif /* _ASM_KEXE_BZIMAGE64_H */ diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c index fb095ba0c02f..705654776c0c 100644 --- a/arch/x86/kernel/kexec-bzimage64.c +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -538,7 +538,7 @@ static int bzImage64_verify_sig(const char *kernel, unsigned long kernel_len) } #endif -struct kexec_file_ops kexec_bzImage64_ops = { +const struct kexec_file_ops kexec_bzImage64_ops = { .probe = bzImage64_probe, .load = bzImage64_load, .cleanup = bzImage64_cleanup, diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c index 1f790cf9d38f..2cdd29d64181 100644 --- a/arch/x86/kernel/machine_kexec_64.c +++ b/arch/x86/kernel/machine_kexec_64.c @@ -30,8 +30,9 @@ #include <asm/set_memory.h> #ifdef CONFIG_KEXEC_FILE -static struct kexec_file_ops *kexec_file_loaders[] = { +const struct kexec_file_ops * const kexec_file_loaders[] = { &kexec_bzImage64_ops, + NULL }; #endif @@ -363,27 +364,6 @@ void arch_crash_save_vmcoreinfo(void) /* arch-dependent functionality related to kexec file-based syscall */ #ifdef CONFIG_KEXEC_FILE -int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, - unsigned long buf_len) -{ - int i, ret = -ENOEXEC; - struct kexec_file_ops *fops; - - for (i = 0; i < ARRAY_SIZE(kexec_file_loaders); i++) { - fops = kexec_file_loaders[i]; - if (!fops || !fops->probe) - continue; - - ret = fops->probe(buf, buf_len); - if (!ret) { - image->fops = fops; - return ret; - } - } - - return ret; -} - void *arch_kexec_kernel_image_load(struct kimage *image) { vfree(image->arch.elf_headers); @@ -398,27 +378,6 @@ void *arch_kexec_kernel_image_load(struct kimage *image) image->cmdline_buf_len); } -int arch_kimage_file_post_load_cleanup(struct kimage *image) -{ - if (!image->fops || !image->fops->cleanup) - return 0; - - return image->fops->cleanup(image->image_loader_data); -} - -#ifdef CONFIG_KEXEC_VERIFY_SIG -int arch_kexec_kernel_verify_sig(struct kimage *image, void *kernel, - unsigned long kernel_len) -{ - if (!image->fops || !image->fops->verify_sig) { - pr_debug("kernel loader does not support signature verification."); - return -EKEYREJECTED; - } - - return image->fops->verify_sig(kernel, kernel_len); -} -#endif - /* * Apply purgatory relocations. * diff --git a/include/linux/kexec.h b/include/linux/kexec.h index f16f6ceb3875..325980537125 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -209,7 +209,7 @@ struct kimage { unsigned long cmdline_buf_len; /* File operations provided by image loader */ - struct kexec_file_ops *fops; + const struct kexec_file_ops *fops; /* Image loader handling the kernel can store a pointer here */ void *image_loader_data; @@ -277,12 +277,13 @@ int crash_shrink_memory(unsigned long new_size); size_t crash_get_memory_size(void); void crash_free_reserved_phys_range(unsigned long begin, unsigned long end); -int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, - unsigned long buf_len); -void * __weak arch_kexec_kernel_image_load(struct kimage *image); -int __weak arch_kimage_file_post_load_cleanup(struct kimage *image); -int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, - unsigned long buf_len); +int _kexec_kernel_image_probe(struct kimage *image, void *buf, + unsigned long buf_len); +void *_kexec_kernel_image_load(struct kimage *image); +int _kimage_file_post_load_cleanup(struct kimage *image); +int _kexec_kernel_verify_sig(struct kimage *image, void *buf, + unsigned long buf_len); + int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, unsigned int relsec); int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 990adae52151..a6d14a768b3e 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -26,34 +26,83 @@ #include <linux/vmalloc.h> #include "kexec_internal.h" +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL}; + #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY static int kexec_calculate_store_digests(struct kimage *image); #else static int kexec_calculate_store_digests(struct kimage *image) { return 0; }; #endif +int _kexec_kernel_image_probe(struct kimage *image, void *buf, + unsigned long buf_len) +{ + const struct kexec_file_ops * const *fops; + int ret = -ENOEXEC; + + for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { + ret = (*fops)->probe(buf, buf_len); + if (!ret) { + image->fops = *fops; + return ret; + } + } + + return ret; +} + /* Architectures can provide this probe function */ int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, unsigned long buf_len) { - return -ENOEXEC; + return _kexec_kernel_image_probe(image, buf, buf_len); +} + +void *_kexec_kernel_image_load(struct kimage *image) +{ + if (!image->fops || !image->fops->load) + return ERR_PTR(-ENOEXEC); + + return image->fops->load(image, image->kernel_buf, + image->kernel_buf_len, image->initrd_buf, + image->initrd_buf_len, image->cmdline_buf, + image->cmdline_buf_len); } void * __weak arch_kexec_kernel_image_load(struct kimage *image) { - return ERR_PTR(-ENOEXEC); + return _kexec_kernel_image_load(image); +} + +int _kimage_file_post_load_cleanup(struct kimage *image) +{ + if (!image->fops || !image->fops->cleanup) + return 0; + + return image->fops->cleanup(image->image_loader_data); } int __weak arch_kimage_file_post_load_cleanup(struct kimage *image) { - return -EINVAL; + return _kimage_file_post_load_cleanup(image); } #ifdef CONFIG_KEXEC_VERIFY_SIG +int _kexec_kernel_verify_sig(struct kimage *image, void *buf, + unsigned long buf_len) +{ + if (!image->fops || !image->fops->verify_sig) { + pr_debug("kernel loader does not support signature verification.\n"); + return -EKEYREJECTED; + } + + return image->fops->verify_sig(buf, buf_len); +} + int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, unsigned long buf_len) { - return -EKEYREJECTED; + return _kexec_kernel_verify_sig(image, buf, buf_len); } #endif
As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup() and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops array and now duplicated among some architectures, let's factor them out. Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> --- arch/powerpc/include/asm/kexec.h | 2 +- arch/powerpc/kernel/kexec_elf_64.c | 2 +- arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------ arch/x86/include/asm/kexec-bzimage64.h | 2 +- arch/x86/kernel/kexec-bzimage64.c | 2 +- arch/x86/kernel/machine_kexec_64.c | 45 +---------------------- include/linux/kexec.h | 15 ++++---- kernel/kexec_file.c | 57 +++++++++++++++++++++++++++-- 8 files changed, 70 insertions(+), 94 deletions(-) -- 2.16.2