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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Spamd-Bar: ++++++++++++ X-Rspamd-Queue-Id: 03BCB21B07 X-Rspamd-Action: add header X-Spam-Flag: YES X-Spam-Score: 12.69 X-Spam-Level: ************ X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Spamd-Result: default: False [12.69 / 50.00]; SPAM_FLAG(5.00)[]; NEURAL_SPAM_LONG(3.50)[1.000]; BAYES_HAM(-3.00)[99.99%]; HFILTER_HOSTNAME_UNKNOWN(2.50)[]; RDNS_NONE(2.00)[]; ONCE_RECEIVED(1.20)[]; HFILTER_HELO_IP_A(1.00)[kunlun.suse.cz]; R_MIXED_CHARSET(0.63)[subject]; HFILTER_HELO_NORES_A_OR_MX(0.30)[kunlun.suse.cz]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.13)[-0.649]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; ARC_NA(0.00)[]; TO_DN_EQ_ADDR_SOME(0.00)[]; MIME_TRACE(0.00)[0:+]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; RCPT_COUNT_TWELVE(0.00)[19]; FREEMAIL_ENVRCPT(0.00)[xtra.co.nz,yahoo.com.au,gmail.com]; TO_DN_SOME(0.00)[]; DNSWL_BLOCKED(0.00)[2a07:de40:b306:2000::2:from]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; RCVD_COUNT_ZERO(0.00)[0]; DKIM_TRACE(0.00)[suse.de:+]; MISSING_XM_UA(0.00)[]; FREEMAIL_CC(0.00)[kernel.org,ellerman.id.au,linux.ibm.com,xenosoft.de,lists.ozlabs.org,vger.kernel.org,infradead.org,xtra.co.nz,yahoo.com.au,gmail.com]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:dkim] X-Spam: Yes On Fri, Sep 18, 2026 at 02:56:40PM +0530, Shrikanth Hegde wrote: > Hi Michal. > > On 9/17/26 7:45 PM, Shrikanth Hegde wrote: > > > > Hi Michal, > > > > > > > > > > Give it a try. > > > > > > > > I am suspecting both lockup, stack corruptions are secondary symptoms here. > > > > While recreate, I have different type of traces. > > > > > > Yes, it does work for the crash I see. > > > > Thanks. Give me sometime to see further on that. Didn't get any time today. > > > This is going to be the fix IMO. It passes all the recreates i have as of now. > (Please ignore the whitespace mangling if any) > > Let me write changelog and send it across. > --- > > diff --git a/arch/powerpc/kernel/trace/ftrace_entry.S b/arch/powerpc/kernel/trace/ftrace_entry.S > index 6599fe3c6234..54c8727b48cd 100644 > --- a/arch/powerpc/kernel/trace/ftrace_entry.S > +++ b/arch/powerpc/kernel/trace/ftrace_entry.S > @@ -220,7 +220,9 @@ > /* Restore gprs */ > .if \allregs == 1 > - REST_GPRS(2, 31, r1) > + REST_GPRS(2, 12, r1) > + /* Do not restore a stale PACA pointer if the task migrated */ > + REST_GPRS(14, 31, r1) > .else > REST_GPRS(3, 10, r1) > #if defined(CONFIG_LIVEPATCH_64) || defined(CONFIG_PPC_FTRACE_OUT_OF_LINE) This also works Thanks Michal