Re: [PATCH 00/16] expand mmap_prepare functionality, port more users

Alexander Gordeev
2025-09-09T08:31:59Z

On Mon, Sep 08, 2025 at 12:10:31PM +0100, Lorenzo Stoakes wrote:

Hi Lorenzo,

I am getting this warning with this series applied:

[Tue Sep 9 10:25:34 2025] ------------[ cut here ]------------
[Tue Sep 9 10:25:34 2025] WARNING: CPU: 0 PID: 563 at mm/memory.c:2942 remap_pfn_range_internal+0x36e/0x420
[Tue Sep 9 10:25:34 2025] Modules linked in: diag288_wdt(E) watchdog(E) ghash_s390(E) des_generic(E) prng(E) aes_s390(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) pkey(E) autofs4(E) overlay(E) squashfs(E) loop(E)
[Tue Sep 9 10:25:34 2025] Unloaded tainted modules: hmac_s390(E):1
[Tue Sep 9 10:25:34 2025] CPU: 0 UID: 0 PID: 563 Comm: makedumpfile Tainted: G E 6.17.0-rc4-gcc-mmap-00410-g87e982e900f0 #288 PREEMPT
[Tue Sep 9 10:25:34 2025] Tainted: [E]=UNSIGNED_MODULE
[Tue Sep 9 10:25:34 2025] Hardware name: IBM 8561 T01 703 (LPAR)
[Tue Sep 9 10:25:34 2025] Krnl PSW : 0704d00180000000 00007fffe07f5ef2 (remap_pfn_range_internal+0x372/0x420)
[Tue Sep 9 10:25:34 2025] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3
[Tue Sep 9 10:25:34 2025] Krnl GPRS: 0000000004044400 001c0f000188b024 0000000000000000 001c0f000188b022
[Tue Sep 9 10:25:34 2025] 000078000c458120 000078000a0ca800 00000f000188b022 0000000000000711
[Tue Sep 9 10:25:34 2025] 000003ffa6e05000 00000f000188b024 000003ffa6a05000 0000000004044400
[Tue Sep 9 10:25:34 2025] 000003ffa7aadfa8 00007fffe2c35ea0 001c000000000000 00007f7fe0faf000
[Tue Sep 9 10:25:34 2025] Krnl Code: 00007fffe07f5ee6: 47000700 bc 0,1792
00007fffe07f5eea: af000000 mc 0,0
#00007fffe07f5eee: af000000 mc 0,0
>00007fffe07f5ef2: a7f4ff11 brc 15,00007fffe07f5d14
00007fffe07f5ef6: b904002b lgr %r2,%r11
00007fffe07f5efa: c0e5000918bb brasl %r14,00007fffe0919070
00007fffe07f5f00: a7f4ff39 brc 15,00007fffe07f5d72
00007fffe07f5f04: e320f0c80004 lg %r2,200(%r15)
[Tue Sep 9 10:25:34 2025] Call Trace:
[Tue Sep 9 10:25:34 2025] [<00007fffe07f5ef2>] remap_pfn_range_internal+0x372/0x420
[Tue Sep 9 10:25:34 2025] [<00007fffe07f5fd4>] remap_pfn_range_complete+0x34/0x70
[Tue Sep 9 10:25:34 2025] [<00007fffe019879e>] remap_oldmem_pfn_range+0x13e/0x1a0
[Tue Sep 9 10:25:34 2025] [<00007fffe0bd3550>] mmap_complete_vmcore+0x520/0x7b0
[Tue Sep 9 10:25:34 2025] [<00007fffe077b05a>] __compat_vma_mmap_prepare+0x3ea/0x550
[Tue Sep 9 10:25:34 2025] [<00007fffe0ba27f0>] pde_mmap+0x160/0x1a0
[Tue Sep 9 10:25:34 2025] [<00007fffe0ba3750>] proc_reg_mmap+0xd0/0x180
[Tue Sep 9 10:25:34 2025] [<00007fffe0859904>] __mmap_new_vma+0x444/0x1290
[Tue Sep 9 10:25:34 2025] [<00007fffe085b0b4>] __mmap_region+0x964/0x1090
[Tue Sep 9 10:25:34 2025] [<00007fffe085dc7e>] mmap_region+0xde/0x250
[Tue Sep 9 10:25:34 2025] [<00007fffe08065fc>] do_mmap+0x80c/0xc30
[Tue Sep 9 10:25:34 2025] [<00007fffe077c708>] vm_mmap_pgoff+0x218/0x370
[Tue Sep 9 10:25:34 2025] [<00007fffe080467e>] ksys_mmap_pgoff+0x2ee/0x400
[Tue Sep 9 10:25:34 2025] [<00007fffe0804a3a>] __s390x_sys_old_mmap+0x15a/0x1d0
[Tue Sep 9 10:25:34 2025] [<00007fffe29f1cd6>] __do_syscall+0x146/0x410
[Tue Sep 9 10:25:34 2025] [<00007fffe2a17e1e>] system_call+0x6e/0x90
[Tue Sep 9 10:25:34 2025] 2 locks held by makedumpfile/563:
[Tue Sep 9 10:25:34 2025] #0: 000078000a0caab0 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x16e/0x370
[Tue Sep 9 10:25:34 2025] #1: 00007fffe3864f50 (vmcore_cb_srcu){.+.+}-{0:0}, at: mmap_complete_vmcore+0x20c/0x7b0
[Tue Sep 9 10:25:34 2025] Last Breaking-Event-Address:
[Tue Sep 9 10:25:34 2025] [<00007fffe07f5d0e>] remap_pfn_range_internal+0x18e/0x420
[Tue Sep 9 10:25:34 2025] irq event stamp: 19113
[Tue Sep 9 10:25:34 2025] hardirqs last enabled at (19121): [<00007fffe0391910>] __up_console_sem+0xe0/0x120
[Tue Sep 9 10:25:34 2025] hardirqs last disabled at (19128): [<00007fffe03918f2>] __up_console_sem+0xc2/0x120
[Tue Sep 9 10:25:34 2025] softirqs last enabled at (4934): [<00007fffe021cb8e>] handle_softirqs+0x70e/0xed0
[Tue Sep 9 10:25:34 2025] softirqs last disabled at (3919): [<00007fffe021b670>] __irq_exit_rcu+0x2e0/0x380
[Tue Sep 9 10:25:34 2025] ---[ end trace 0000000000000000 ]---

Thanks!