Re: [PATCH v7 2/7] kexec: define functions to map and unmap segments

[Mimi Zohar <zohar@linux.ibm.com>]

On Mon, 2025-02-10 at 09:06 -0800, steven chen wrote:
> On 2/7/2025 11:15 AM, Mimi Zohar wrote:
> > Hi Steven,
> > 
> > On Mon, 2025-02-03 at 15:20 -0800, steven chen wrote:
> > > Currently, the mechanism to map and unmap segments to the kimage
> > > structure is not available to the subsystems outside of kexec.  This
> > > functionality is needed when IMA is allocating the memory segments
> > > during kexec 'load' operation.  Implement functions to map and unmap
> > > segments to kimage.
> > > 
> > > Implement kimage_map_segment() to enable mapping of IMA buffer source
> > > pages to the kimage structure post kexec 'load'.  This function,
> > > accepting a kimage pointer, an address, and a size, will gather the
> > > source pages within the specified address range, create an array of page
> > > pointers, and map these to a contiguous virtual address range.  The
> > > function returns the start of this range if successful, or NULL if
> > > unsuccessful.
> > > 
> > > Implement kimage_unmap_segment() for unmapping segments
> > > using vunmap().
> > > 
> > > From: Tushar Sugandhi <tusharsu@linux.microsoft.com>
> > > Author: Tushar Sugandhi <tusharsu@linux.microsoft.com>
> > > Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
> > > Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
> > I don't recall previously adding my "Reviewed-by" tag.
> > 
> > Eric, I'd appreciate your reviewing this and the subsequent patch "[PATCH v7 3/7]
> > ima: kexec: skip IMA segment validation after kexec soft reboot" in particular.
> Hi Eric, Could you help to review this patch as Mimi mentioned? Thanks!
> > 
> > > Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>

Steven, since these patches impact kdump, before re-posting the patch set, please
include the following tags before your Signed-off-by tag on the kexec patches.

Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Baoquan He <bhe@redhat.com>                                             
Cc: Vivek Goyal <vgoyal@redhat.com>                                         
Cc: Dave Young <dyoung@redhat.com>   

> > > Signed-off-by: steven chen <chenste@linux.microsoft.com>

thanks,

Mimi