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Howlett" , Matthew Wilcox , Vlastimil Babka , "Paul E . McKenney" , Jann Horn , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Shuah Khan , linux-kselftest@vger.kernel.org, linux-api@vger.kernel.org, John Hubbard , Juan Yescas Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, Feb 21, 2025 at 3:04=E2=80=AFAM Lorenzo Stoakes wrote: > > On Thu, Feb 20, 2025 at 10:08:36AM -0800, Kalesh Singh wrote: > > On Thu, Feb 20, 2025 at 8:22=E2=80=AFAM Suren Baghdasaryan wrote: > > > > > > On Thu, Feb 20, 2025 at 5:18=E2=80=AFAM Lorenzo Stoakes > > > wrote: > > > > > > > > On Thu, Feb 20, 2025 at 01:44:20PM +0100, David Hildenbrand wrote: > > > > > On 20.02.25 11:15, Lorenzo Stoakes wrote: > > > > > > On Thu, Feb 20, 2025 at 11:03:02AM +0100, David Hildenbrand wro= te: > > > > > > > > > Your conclusion is 'did not participate with upstream'; I= don't agree with > > > > > > > > > that. But maybe you and Kalesh have a history on that tha= t let's you react > > > > > > > > > on his questions IMHO more emotionally than it should hav= e been. > > > > > > > > > > > > > > > > This is wholly unfair, I have been very reasonable in respo= nse to this > > > > > > > > thread. I have offered to find solutions, I have tried to u= nderstand the > > > > > > > > problem in spite of having gone to great lengths to try to = discuss the > > > > > > > > limitations of the proposed approach in every venue I possi= bly could. > > > > > > > > > > > > > > > > I go out of my way to deal professionally and objectively w= ith what is > > > > > > > > presented. Nothing here is emotional. So I'd ask that you p= lease abstain > > > > > > > > from making commentary like this which has no basis. > > > > > > > > > > > > > > I appreciate everything you write below. But this request is = just > > > > > > > impossible. I will keep raising my opinion and misunderstandi= ngs will > > > > > > > happen. > > > > > > > > > > > > Well I wouldn't ask you not to express your opinion David, you = know I respect > > > > > > and like you, and by all means push back hard or call out what = you think is bad > > > > > > behaviour :) > > > > > > > > > > > > I just meant to say, in my view, that there was no basis, but I= appreciate > > > > > > miscommunications happen. > > > > > > > So apologies if I came off as being difficult or rude, it act= ually > > > > > wasn't > > > > > > intended. And to re-emphasise - I have zero personal issue with= anybody in this > > > > > > thread whatsoever! > > > > > > > > > > It sounded to me like you were trying to defend your work (again,= IMHO too > > > > > emotionally, and I might have completely misinterpreted that) and= slowly > > > > > switching to "friendly fire" (towards me). Apologies from my side= if I > > > > > completely misunderstood/misinterpreted that. > > > > > > > > Right this was not at all my intent, sorry if it seemed that way. I= may well > > > > have communicated terribly, so apologies on my side too. > > > > Hi everyone, > > > > Thank you for all the discussion. > > > > I don't find any personal issues with the communication in this > > thread, but I appreciate David being the object voice of reason. > > > > I understand it can be frustrating since you have made many efforts to > > communicate these tradeoffs. Unfortunately these issues were not known > > for the file-backed ELF guard regions for my particular use case. > > > > > > > > Sorry for being late to the party. Was sick for a couple of days. > > > Lorenzo is right, there was a breakdown in communication at Google an= d > > > he has all the rights to be upset. The issue with obfuscators should > > > have been communicated once it was discovered. I was in regular > > > discussions with Lorenzo but wasn't directly involved with this > > > particular project and wasn't aware or did not realize that the > > > obfuscator issue renders guards unusable for this usecase. My > > > apologies, I should have asked more questions about it. I suspect > > > Lorenzo would have implemented this anyway... > > > > > > > Suren's use case is different from mine and this design fits perfectly > > for anon guard regions from the allocator. :) > > > > So I think in conclusion, these aren't VMAs and shouldn't be treated > > as such; we will advertise them from pagemap for those who need to > > know. > > > > Thanks Kalesh, glad there were no issues here and we have found > constructive common ground! :) > > It turns out implementing the pagemap side of things is _really_ > straightforward, so I'll be sending a series for that shortly. Hopefully > this provides some basis for whichever use cases need this information, a= s > it is the best and least invasive place for this information at this stag= e. Hi Lorenzo, Reviewed your patches, agreed that is the cleanest way to advertise this information. Thanks, Kalesh > > Cheers, Lorenzo > > > -- Kalesh