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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Authority-Analysis: v=2.4 cv=HppG3UTS c=1 sm=1 tr=0 ts=6a27d43a cx=c_pps a=aDMHemPKRhS1OARIsFnwRA==:117 a=aDMHemPKRhS1OARIsFnwRA==:17 a=IkcTkHD0fZMA:10 a=FelO9ux0wxsA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=uAbxVGIbfxUO_5tXvNgY:22 a=jDEF8yXcYhEeGhTqFzAA:9 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: uy5uA-4LAkQXosgRLeYKG9__XiD3wO41 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNjA5MDA3OSBTYWx0ZWRfX1LnRsX/NslW6 10Kx6AfRwuDC7yqNSV+PtaezZSUOJDVDq6q3XnXnzbRlJRjpCtT1oklrDK7q+VkLgMaKH/HX1Tk sMxdgQi3xva78lBGS65KWRSTw2S6Fd5lInhoYTGOOzyPAsxwXD45x4qiM6Z+CaUAoup/Yl5kgFO PPEyoQaMcSgn+LDoqb6OxTi6dBbzzaMy4mx4LUFNNeY9XkI3issRge1Wd4NF9gUdP5HWdtS8oW/ 5/2/qPQq67is8P7wW0AgUKPOncjeXYW64q+Be8cFrMgYeStTk6VYNod/tAyQUqRq6qW6O7J08KB fpbt0rn3Y+vu4duyRQc2nD6ppmvz92i7kPjiipGMS+EzX041vQw00sgXaUB0b7ywyIgTFyPpkju TqGxWethQMS3UEjpwL6yo9YYTh+pTT27uZunERfXhZ2Xg91zVHY8fajLwTfP6TAIRXwPFZNsHwU 3TeaMPSXZI3DsLHaPqg== X-Proofpoint-ORIG-GUID: l1yAjDp3acC5UYb8nk8EW-AoTRozIh-V X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.125,FMLib:17.12.100.49 definitions=2026-06-09_02,2026-06-09_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 adultscore=0 phishscore=0 malwarescore=0 impostorscore=0 priorityscore=1501 clxscore=1015 bulkscore=0 spamscore=0 suspectscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2605210000 definitions=main-2606090079 On 08/06/26 21:09, Bjorn Helgaas wrote: > On Wed, May 27, 2026 at 11:38:14PM +0530, Aditya Gupta wrote: >> For opencapi phb direct slots, the .pdev for php_slots will be NULL >> >> Various sections of the code in pnv_php can do a null dereference and >> crash the kernel. >> >> Originally, the issue was hit during boot: >> >> [ 1.568588] PowerPC PowerNV PCI Hotplug Driver version: 0.1 >> [ 1.569722] BUG: Kernel NULL pointer dereference at 0x00000074 >> [ 1.569811] Faulting instruction address: 0xc000000000b75fd0 >> [ 1.569890] Oops: Kernel access of bad area, sig: 11 [#1] >> [ 1.569963] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA PowerNV >> ... >> [ 1.571492] NIP [c000000000b75fd0] pnv_php_get_adapter_state+0x60/0x154 >> [ 1.571604] LR [c000000000b75fbc] pnv_php_get_adapter_state+0x4c/0x154 >> [ 1.571690] Call Trace: >> [ 1.571725] [c000c0000688f990] [c000000000b75fbc] pnv_php_get_adapter_state+0x4c/0x154 (unreliable) >> [ 1.571783] [c000c0000688fa20] [c000000000b78bd0] pnv_php_enable+0x94/0x378 >> [ 1.571951] [c000c0000688fac0] [c000000000b7912c] pnv_php_register_one.isra.0+0x11c/0x1e0 > Drop timestamps since they don't add useful information. > > Indent quoted material by two spaces to reduce wrapping. > > Run "git log --oneline drivers/pci/hotplug/pnv_php.c" and "git log > --oneline drivers/pci/hotplug/" and match subject line style. > >> This occurs for hotplug slots on root buses where bus->self == NULL, >> such as OpenCAPI PHB direct slots. An added debug print (not part of >> this patch) confirmed it was opencapi: > Style "OpenCAPI" and "PHB" consistently in commit log and subject. Thanks for the review Bjorn, fixed the description and have sent the patch again as v3. In v3, I have sent the patch #1 independently for rc, and will send the rework patches (patches #2 and #3) separately, since I have to do extra fixes for pre-existing issues pointed by sashiko. Thanks, - Aditya G