On 02/25/25 at 10:35am, steven chen wrote: > On 2/24/2025 4:18 PM, Baoquan He wrote: > > On 02/24/25 at 03:05pm, steven chen wrote: > > > On 2/23/2025 10:14 PM, Baoquan He wrote: > > > > Hi Steve, Mimi, > > > > > > > > On 02/18/25 at 02:54pm, 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. > > > > I am done with the whole patchset understanding. My concern is if this > > > > TPM PCRs content can be carried over through newly introduced KHO. I can > > > > see that these patchset doesn't introduce too much new code changes, > > > > while if many conponents need do this, kexec reboot will be patched all > > > > over its body and become ugly and hard to maintain. > > > > > > > > Please check Mike Rapoport's v4 patchset to see if IMA can register > > > > itself to KHO and do somthing during 2nd kernel init to restore those > > > > TPM PCRs content to make sure all measurement logs are read correctly. > > > > [PATCH v4 00/14] kexec: introduce Kexec HandOver (KHO) > > > > > > > > Thanks > > > > Baoquan > > > Hi Baoquan, > > > > > > For IMA, it appears that there are no current issues with TPM PCRs after a > > > kernel soft reboot. > > I mean using KHO to hold in 1st kernel and restore the IMA log in 2nd > > kernel. > > > > > This patches is used to get currently missed IMA measurements during the > > > kexec process copied to new kernel after the kernel soft reboot. I think > > > it's ok to leave it at current location: it will be easy to maintain for > > > IMA. > > Yeah, but I am saying this patchset increase unnecessary code > > complexity in kexec code maintaining. > > > > > Overall, for these patches, do you see any major blockers for kexec? > > > > > > If you have any specific concerns or need further details, please let me > > > know. > > I have no concerns for this patchset implementation itself, I saw you using > > vmap to maping the possible scattered source pages smartly and taking > > the mapped buffer pointers to update later duing kexec jumping. That's very > > great and clever method. BUT I am concerned about the solution, if we > > can make use of the existed way of KHO to implement it more simply. Could > > you please do investigation? > > Hi Baoquan, > > I will conduct an investigation. Thank you for your comments. Thanks a lot, Steven.
