[6.1.0-rc2] insecure W+X mapping warning during kdump kernel boot

[Sachin Sant]

With CONFIG_DEBUG_WX=y I am observing following warning
During kdump kernel boot. This warning is not seen during production
kernel boot. Kernel crash dump is captured correctly.

------------[ cut here ]------------
[   11.541311] powerpc/mm: Found insecure W+X mapping at address 00000000749d3849/0xc000000000000000
[   11.541328] WARNING: CPU: 28 PID: 1 at arch/powerpc/mm/ptdump/ptdump.c:194 note_page+0x408/0x430
[   11.541342] Modules linked in:
[   11.541348] CPU: 28 PID: 1 Comm: swapper/28 Not tainted 6.1.0-rc2-gb229b6ca5abb #1
[   11.541356] Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1030.00 (NH1030_026) hv:phyp pSeries
[   11.541364] NIP:  c0000000100b1ac8 LR: c0000000100b1ac4 CTR: 0000000000725d90
[   11.541370] REGS: c0000000156f7720 TRAP: 0700   Not tainted  (6.1.0-rc2-gb229b6ca5abb)
[   11.541377] MSR:  800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  CR: 28000822  XER: 00000006
[   11.541393] CFAR: c000000010157514 IRQMASK: 0 
[   11.541393] GPR00: c0000000100b1ac4 c0000000156f79c0 c00000001135eb00 0000000000000055 
[   11.541393] GPR04: 00000000fffeffff c0000000156f7780 c0000000156f7778 0000000000000000 
[   11.541393] GPR08: 00000000fffeffff 0000000000000000 c0000000125d73b8 c000000083dfffe8 
[   11.541393] GPR12: 0000000000000000 c000000012e12400 c000000010f3b5f0 c0000000001f0000 
[   11.541393] GPR16: c000000012b2dba0 0000000000000001 c0000000156f7bd8 c00000008ffc0010 
[   11.541393] GPR20: c000000010f3b5f0 c00000003fffffff c000000000010000 c000000012b2dbb0 
[   11.541393] GPR24: c000000012b2dba8 c00000008ffe0000 c000000000200000 c000000000010000 
[   11.541393] GPR28: c00000000001018e 0000000000000004 c00000000001018e c0000000156f7cc0 
[   11.541462] NIP [c0000000100b1ac8] note_page+0x408/0x430
[   11.541469] LR [c0000000100b1ac4] note_page+0x404/0x430
[   11.541476] Call Trace:
[   11.541478] [c0000000156f79c0] [c0000000100b1ac4] note_page+0x404/0x430 (unreliable)
[   11.541488] [c0000000156f7a70] [c000000010550a14] ptdump_pte_entry+0xa4/0x100
[   11.541498] [c0000000156f7ab0] [c00000001049849c] walk_pgd_range+0x8ec/0xb20
[   11.541507] [c0000000156f7bb0] [c000000010498bf4] walk_page_range_novma+0x74/0xc0
[   11.541515] [c0000000156f7c10] [c000000010550e48] ptdump_walk_pgd+0x98/0x170
[   11.541523] [c0000000156f7c60] [c0000000100b1b84] ptdump_check_wx+0x94/0x100
[   11.541532] [c0000000156f7d40] [c000000010094cb0] mark_rodata_ro+0x30/0x70
[   11.541540] [c0000000156f7da0] [c00000001001282c] kernel_init+0x8c/0x1b0
[   11.541548] [c0000000156f7e10] [c00000001000cf60] ret_from_kernel_thread+0x5c/0x64
[   11.541556] Instruction dump:
[   11.541560] eb410080 ebc100a0 7c0803a6 4bfffc94 3c62ffe1 39200001 3d42016b 7ca42b78 
[   11.541571] 3863e5c0 992a9e23 480a59ed 60000000 <0fe00000> fae10068 fb010070 fb210078 
[   11.541583] ---[ end trace 0000000000000000 ]—


- Sachin