On Thu, Sep 27, 2018 at 03:19:52PM +0800, Lianbo Jiang wrote: > When SME is enabled in the first kernel, we will allocate unencrypted pages > for kdump in order to be able to boot the kdump kernel like kexec.
This is not what the commit does - it marks the control pages as decrypted when SME. Why doesn't the commit message state that and why is this being done? > Signed-off-by: Lianbo Jiang <[email protected]> > Reviewed-by: Tom Lendacky <[email protected]> > --- > kernel/kexec_core.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c > index 23a83a4da38a..e7efcd1a977b 100644 > --- a/kernel/kexec_core.c > +++ b/kernel/kexec_core.c > @@ -471,6 +471,16 @@ static struct page > *kimage_alloc_crash_control_pages(struct kimage *image, > } > } > > + if (pages) { > + /* > + * For kdump, we need to ensure that these pages are > + * unencrypted pages if SME is enabled. Remember to always call unencrypted pages "decrypted" - this is the convention we agreed upon and it should keep the confusion level at minimum to others staring at this code. > + * By the way, it is unnecessary to call the arch_ > + * kexec_pre_free_pages(), which will make the code > + * become more simple. > + */ This second sentence I don't understand... > + arch_kexec_post_alloc_pages(page_address(pages), 1 << order, 0); > + } > return pages; > } > > @@ -867,6 +877,7 @@ static int kimage_load_crash_segment(struct kimage *image, > result = -ENOMEM; > goto out; > } > + arch_kexec_post_alloc_pages(page_address(page), 1, 0); > ptr = kmap(page); > ptr += maddr & ~PAGE_MASK; > mchunk = min_t(size_t, mbytes, > @@ -884,6 +895,7 @@ static int kimage_load_crash_segment(struct kimage *image, > result = copy_from_user(ptr, buf, uchunk); > kexec_flush_icache_page(page); > kunmap(page); > + arch_kexec_pre_free_pages(page_address(page), 1); > if (result) { > result = -EFAULT; > goto out; > -- > 2.17.1 > -- Regards/Gruss, Boris. SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
