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Marchesi" , Beau Belgrave , Linus Torvalds , Andrew Morton , Jens Axboe , Florian Weimer , Sam James References: <20250710163522.3195293-1-jremus@linux.ibm.com> <20250710163522.3195293-13-jremus@linux.ibm.com> <63665c54-db44-452f-b321-1162ff6c3fe4@linux.ibm.com> <20250801123647.9905A43-hca@linux.ibm.com> Content-Language: en-US From: Jens Remus Organization: IBM Deutschland Research & Development GmbH In-Reply-To: <20250801123647.9905A43-hca@linux.ibm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=ZNPXmW7b c=1 sm=1 tr=0 ts=688ce1fb cx=c_pps a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17 a=IkcTkHD0fZMA:10 a=2OwXVqhp2XgA:10 a=VnNF1IyMAAAA:8 a=saB0obKPUKYBhUFmqKIA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-ORIG-GUID: TfHxs6ezsH5a6J-EX8IXssNmsml7JaqA X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwODAxMDEyMSBTYWx0ZWRfXzTYt6I3J49MX 8bKiaxhUBy0wbPPaSCj0dMwdakpE/Mwo7cOqnnDjqUx9fqvwRxow/MhyN2W8XPyUGRQHwYPZOU4 Mb1xs+K7iRCX6TymGTr5a3MnTevdSeIQk0izi6OM3THayyvdFvtkNSUPLsifAe0mtGw6x5nSW3/ aFg9V3K+pM4XmBkOCFRAv22UEP9ibKCgY+ScwktqJVs1UOZXaMAX7LbfrAdSegwxxab/NBYuwwR fYBKkwMuRGsY2Oh6tQEgpDLX6P2kjclmoZekUnFB/mPuA1oXQNebVX1/BHeglKBZNu+Rs8Bh8lH mDASzmTtmJjF+/rSqpIYE8pvKiOD8QlwijypLU9wbRLfnZNE0r7PNZOF6lQIl7qiUO4lrFcA/VJ CqdL6r42pXpHNl+iKiZtLlCg+vYjfbI1wQ4vhzLqJwKXimFh6QkaoiKFNACHX1akPc/i53Tw X-Proofpoint-GUID: TfHxs6ezsH5a6J-EX8IXssNmsml7JaqA X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-08-01_05,2025-08-01_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 clxscore=1015 mlxlogscore=968 adultscore=0 priorityscore=1501 impostorscore=0 suspectscore=0 malwarescore=0 lowpriorityscore=0 spamscore=0 phishscore=0 mlxscore=0 classifier=spam authscore=0 authtc=n/a authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2505280000 definitions=main-2508010121 On 8/1/2025 2:36 PM, Heiko Carstens wrote: > On Thu, Jul 17, 2025 at 10:19:54PM -0700, Josh Poimboeuf wrote: >> On Thu, Jul 17, 2025 at 02:20:12PM +0200, Jens Remus wrote: >> I believe stack_trace_save_user() is only used by ftrace, and that will >> no longer be needed once ftrace starts using unwind_user. >> >> Maybe Heiko knows if that backchain user stacktrace code has any users? >> >> If distros aren't building with -mbackchain, maybe backchain support can >> be considered obsoleted by sframe, and we can get away with not >> implementing it. > > I guess that's a valid option. I know only of some special cases where > users compile everything on their own with -mbackchain to make this > work on a per-case basis. It shouldn't cause to much pain for them to > switch to sframe, as soon as that is available. Let me have another stab at a cleaner implementation. Shouldn't be too much effort. We can then decide whether to leave it out or not. Will be away from keyboard for a few weeks. Regards, Jens -- Jens Remus Linux on Z Development (D3303) +49-7031-16-1128 Office jremus@de.ibm.com IBM IBM Deutschland Research & Development GmbH; Vorsitzender des Aufsichtsrats: Wolfgang Wendt; Geschäftsführung: David Faller; Sitz der Gesellschaft: Böblingen; Registergericht: Amtsgericht Stuttgart, HRB 243294 IBM Data Privacy Statement: https://www.ibm.com/privacy/