On Fri, 2025-04-18 at 12:36 +0800, Baoquan He wrote: > On 04/15/25 at 07:10pm, steven chen wrote: > > From: Steven Chen <chen...@linux.microsoft.com> > ^^^^^^
As James Bottomley previously explained[1], if you haven't made any changes to Tushar's patch, then the very first line of the patch description would be "From: Tushar Sugandhi <tusha...@linux.microsoft.com>" followed by a blank line. If there is a minor change, you would add "<your email address>: explanation". For example: Steven Chen <chen...@linux.microsoft.com>: modified patch description [1] https://lore.kernel.org/lkml/58e70121aaee33679ac295847197c1e5511b2a81.ca...@hansenpartnership.com/ > > > > Implement kimage_map_segment() to enable IMA to map the measurement log > > list to the kimage structure during the kexec 'load' stage. This function > > gathers the source pages within the specified address range, and maps them > > to a contiguous virtual address range. > > > > This is a preparation for later usage. > > > > Implement kimage_unmap_segment() for unmapping segments using vunmap(). > > > > From: Tushar Sugandhi <tusha...@linux.microsoft.com> > ^^^^^^ Neither "Author:" nor "From:" belong here. Please remove. > > Signed-off-by: Tushar Sugandhi <tusha...@linux.microsoft.com> > ^^^^^^^ Having Tushar's "Signed-off-by" tag and yours below indicate that you modified the original author's patch. thanks, Mimi > > Cc: Eric Biederman <ebied...@xmission.com> > > Cc: Baoquan He <b...@redhat.com> > > Cc: Vivek Goyal <vgo...@redhat.com> > > Cc: Dave Young <dyo...@redhat.com> > > Signed-off-by: steven chen <chen...@linux.microsoft.com> > ^^^^^ > > The signing on this patch is a little confusing. I can't see who is the > real author, who is the co-author, between you and Tushar. You may need > to refer to Documentation/process/5.Posting.rst to make that clear. > > > Acked-by: Baoquan He <b...@redhat.com> > > --- > > include/linux/kexec.h | 6 +++++ > > kernel/kexec_core.c | 54 +++++++++++++++++++++++++++++++++++++++++++ > > 2 files changed, 60 insertions(+) > > > > diff --git a/include/linux/kexec.h b/include/linux/kexec.h > > index f0e9f8eda7a3..7d6b12f8b8d0 100644 > > --- a/include/linux/kexec.h > > +++ b/include/linux/kexec.h > > @@ -467,13 +467,19 @@ extern bool kexec_file_dbg_print; > > #define kexec_dprintk(fmt, arg...) \ > > do { if (kexec_file_dbg_print) pr_info(fmt, ##arg); } while (0) > > > > +extern void *kimage_map_segment(struct kimage *image, unsigned long addr, > > unsigned long size); > > +extern void kimage_unmap_segment(void *buffer); > > #else /* !CONFIG_KEXEC_CORE */ > > struct pt_regs; > > struct task_struct; > > +struct kimage; > > static inline void __crash_kexec(struct pt_regs *regs) { } > > static inline void crash_kexec(struct pt_regs *regs) { } > > static inline int kexec_should_crash(struct task_struct *p) { return 0; } > > static inline int kexec_crash_loaded(void) { return 0; } > > +static inline void *kimage_map_segment(struct kimage *image, unsigned long > > addr, unsigned long size) > > +{ return NULL; } > > +static inline void kimage_unmap_segment(void *buffer) { } > > #define kexec_in_progress false > > #endif /* CONFIG_KEXEC_CORE */ > > > > diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c > > index c0bdc1686154..a5e378e1dc7f 100644 > > --- a/kernel/kexec_core.c > > +++ b/kernel/kexec_core.c > > @@ -867,6 +867,60 @@ int kimage_load_segment(struct kimage *image, > > return result; > > } > > > > +void *kimage_map_segment(struct kimage *image, > > + unsigned long addr, unsigned long size) > > +{ > > + unsigned long src_page_addr, dest_page_addr = 0; > > + unsigned long eaddr = addr + size; > > + kimage_entry_t *ptr, entry; > > + struct page **src_pages; > > + unsigned int npages; > > + void *vaddr = NULL; > > + int i; > > + > > + /* > > + * Collect the source pages and map them in a contiguous VA range. > > + */ > > + npages = PFN_UP(eaddr) - PFN_DOWN(addr); > > + src_pages = kmalloc_array(npages, sizeof(*src_pages), GFP_KERNEL); > > + if (!src_pages) { > > + pr_err("Could not allocate ima pages array.\n"); > > + return NULL; > > + } > > + > > + i = 0; > > + for_each_kimage_entry(image, ptr, entry) { > > + if (entry & IND_DESTINATION) { > > + dest_page_addr = entry & PAGE_MASK; > > + } else if (entry & IND_SOURCE) { > > + if (dest_page_addr >= addr && dest_page_addr < eaddr) { > > + src_page_addr = entry & PAGE_MASK; > > + src_pages[i++] = > > + virt_to_page(__va(src_page_addr)); > > + if (i == npages) > > + break; > > + dest_page_addr += PAGE_SIZE; > > + } > > + } > > + } > > + > > + /* Sanity check. */ > > + WARN_ON(i < npages); > > + > > + vaddr = vmap(src_pages, npages, VM_MAP, PAGE_KERNEL); > > + kfree(src_pages); > > + > > + if (!vaddr) > > + pr_err("Could not map ima buffer.\n"); > > + > > + return vaddr; > > +} > > + > > +void kimage_unmap_segment(void *segment_buffer) > > +{ > > + vunmap(segment_buffer); > > +} > > + > > struct kexec_load_limit { > > /* Mutex protects the limit count. */ > > struct mutex mutex; > > -- > > 2.43.0 > > > >
