On Wed, Nov 23, 2016 at 07:51:20PM +0000, Russell King - ARM Linux wrote:
> On Wed, Nov 23, 2016 at 07:15:39PM +0000, Jason Cooper wrote:
> > ------- oops from v4.8.6 #2 ------------------------------------------
> > [42059.303625] Unable to handle kernel NULL pointer dereference at virtual address 00000020
> > [42059.311799] pgd = c0004000
> > [42059.314522] [00000020] *pgd=00000000
> > [42059.318162] Internal error: Oops: 17 [#1] SMP ARM
> > [42059.322889] Modules linked in: ath9k ath9k_common ath9k_hw ath
> > [42059.328809] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.8.6 #37
> > [42059.334755] Hardware name: Marvell Armada 370/XP (Device Tree)
> > [42059.340613] task: c0b091c0 task.stack: c0b00000
> > [42059.345176] PC is at ath_cmn_process_fft+0xa0/0x578 [ath9k_common]
> > [42059.351388] LR is at ath_cmn_process_fft+0xc4/0x578 [ath9k_common]
> > [42059.357598] pc : [<bf07bec4>] lr : [<bf07bee8>] psr: 80000153
> > [42059.357598] sp : c0b01cd0 ip : 00000000 fp : 00000000
> > [42059.369127] r10: c0b034d4 r9 : 00000069 r8 : 0000006c
> > [42059.374374] r7 : 00000000 r6 : dcfbd340 r5 : c0b03da0 r4 : 00000000
> > [42059.380930] r3 : 00000001 r2 : 00000008 r1 : 00000004 r0 : 00000000
>
> Well, the good news is that it's reproducable.
>
> It looks like it could be this:
>
> static int
> ath_cmn_is_fft_buf_full(struct ath_spec_scan_priv *spec_priv)
> {
> for_each_online_cpu(i)
> ret += relay_buf_full(rc->buf[i]);
>
> where i = 8 (r2) and rc->buf is r7. That's just a guess though, as
> there's precious little to go on with the Code: line - modern GCCs
> don't give us much with the Code: line anymore to figure out what's
> going on without the exact object files.
>
> e5933000 ldr r3, [r3]
> e1d330b4 ldrh r3, [r3, #4]
> e58d3030 str r3, [sp, #48] ; 0x30
> ea000002 b 1c <foo+0x1c>
> e7970102 ldr r0, [r7, r2, lsl #2]
>
As requested on irc:
-------------->8--------------------------------------------------------
drivers/net/wireless/ath/ath9k/common-spectral.o: file format elf32-littlearm
Disassembly of section .text:
...
00000754 <ath_cmn_process_fft>:
754: e92d4ff0 push {r4, r5, r6, r7, r8, r9, sl, fp, lr}
758: e24dd0d4 sub sp, sp, #212 ; 0xd4
75c: e1a04002 mov r4, r2
760: e1a06001 mov r6, r1
764: e58d0024 str r0, [sp, #36] ; 0x24
768: e3a01000 mov r1, #0
76c: e58d2018 str r2, [sp, #24]
770: e28d0049 add r0, sp, #73 ; 0x49
774: e3a02087 mov r2, #135 ; 0x87
778: ebfffffe bl 0 <memset>
77c: e5d44007 ldrb r4, [r4, #7]
780: e20430fd and r3, r4, #253 ; 0xfd
784: e3530024 cmp r3, #36 ; 0x24
788: 13540005 cmpne r4, #5
78c: 13a04001 movne r4, #1
790: 03a04000 moveq r4, #0
794: 13a00000 movne r0, #0
798: 0a000001 beq 7a4 <ath_cmn_process_fft+0x50>
79c: e28dd0d4 add sp, sp, #212 ; 0xd4
7a0: e8bd8ff0 pop {r4, r5, r6, r7, r8, r9, sl, fp, pc}
7a4: e59d3018 ldr r3, [sp, #24]
7a8: e1d380b4 ldrh r8, [r3, #4]
7ac: e2489003 sub r9, r8, #3
7b0: e0863009 add r3, r6, r9
7b4: e5d30002 ldrb r0, [r3, #2]
7b8: e2000010 and r0, r0, #16
7bc: e21000ff ands r0, r0, #255 ; 0xff
7c0: 0afffff5 beq 79c <ath_cmn_process_fft+0x48>
7c4: e59d3024 ldr r3, [sp, #36] ; 0x24
7c8: e3005000 movw r5, #0
7cc: e3405000 movt r5, #0
7d0: e3e0b000 mvn fp, #0
7d4: e5932000 ldr r2, [r3]
7d8: e5937004 ldr r7, [r3, #4]
7dc: e5923438 ldr r3, [r2, #1080] ; 0x438
7e0: e58d2010 str r2, [sp, #16]
7e4: e5933000 ldr r3, [r3]
7e8: e1d330b4 ldrh r3, [r3, #4]
7ec: e58d3030 str r3, [sp, #48] ; 0x30
7f0: ea000002 b 800 <ath_cmn_process_fft+0xac>
7f4: e7970102 ldr r0, [r7, r2, lsl #2]
7f8: ebfffffe bl 0 <relay_buf_full>
7fc: e0844000 add r4, r4, r0
800: e300a000 movw sl, #0
804: e28b2001 add r2, fp, #1
808: e340a000 movt sl, #0
80c: e3a01004 mov r1, #4
810: e1a0000a mov r0, sl
814: ebfffffe bl 0 <_find_next_bit_le>
818: e5953000 ldr r3, [r5]
81c: e1500003 cmp r0, r3
820: e1a0b000 mov fp, r0
824: e2802008 add r2, r0, #8
828: bafffff1 blt 7f4 <ath_cmn_process_fft+0xa0>
82c: e59a0000 ldr r0, [sl]
830: e200000f and r0, r0, #15
834: ebfffffe bl 0 <__sw_hweight32>
838: e1540000 cmp r4, r0
83c: 0a000092 beq a8c <ath_cmn_process_fft+0x338>
840: e59d3010 ldr r3, [sp, #16]
844: e5932030 ldr r2, [r3, #48] ; 0x30
848: e5923018 ldr r3, [r2, #24]
84c: e3530001 cmp r3, #1
850: 0a000090 beq a98 <ath_cmn_process_fft+0x344>
854: 3a000119 bcc cc0 <ath_cmn_process_fft+0x56c>
858: e3530002 cmp r3, #2
85c: 1a000110 bne ca4 <ath_cmn_process_fft+0x550>
860: e3003000 movw r3, #0
864: e5921014 ldr r1, [r2, #20]
868: e1a00003 mov r0, r3
86c: e592301c ldr r3, [r2, #28]
870: e3002000 movw r2, #0
874: e3a0b087 mov fp, #135 ; 0x87
878: e1a0c002 mov ip, r2
87c: e1a02000 mov r2, r0
880: e3402000 movt r2, #0
884: e58d2034 str r2, [sp, #52] ; 0x34
888: e1a0200c mov r2, ip
88c: e3a0a08a mov sl, #138 ; 0x8a
890: e3402000 movt r2, #0
894: e58d2044 str r2, [sp, #68] ; 0x44
898: e1d120b4 ldrh r2, [r1, #4]
89c: e3a01080 mov r1, #128 ; 0x80
8a0: e58d1020 str r1, [sp, #32]
8a4: e1520003 cmp r2, r3
8a8: 33a03003 movcc r3, #3
8ac: 23a03002 movcs r3, #2
8b0: e58d3038 str r3, [sp, #56] ; 0x38
8b4: e2483002 sub r3, r8, #2
8b8: e58d3014 str r3, [sp, #20]
8bc: e3530000 cmp r3, #0
8c0: da000071 ble a8c <ath_cmn_process_fft+0x338>
8c4: e3a03000 mov r3, #0
8c8: e28aa002 add sl, sl, #2
8cc: e1a04003 mov r4, r3
8d0: e58d3028 str r3, [sp, #40] ; 0x28
8d4: e1a05004 mov r5, r4
8d8: e24b3001 sub r3, fp, #1
8dc: e1a07006 mov r7, r6
8e0: e58d302c str r3, [sp, #44] ; 0x2c
8e4: e58db01c str fp, [sp, #28]
8e8: e1a03009 mov r3, r9
8ec: e58d8010 str r8, [sp, #16]
8f0: e1a09004 mov r9, r4
8f4: ea00002c b 9ac <ath_cmn_process_fft+0x258>
8f8: e3520007 cmp r2, #7
8fc: e1a05003 mov r5, r3
900: e086b004 add fp, r6, r4
904: 8a00006f bhi ac8 <ath_cmn_process_fft+0x374>
908: e59d202c ldr r2, [sp, #44] ; 0x2c
90c: e1530002 cmp r3, r2
910: a3a09001 movge r9, #1
914: ba0000dd blt c90 <ath_cmn_process_fft+0x53c>
918: e59d101c ldr r1, [sp, #28]
91c: e2812002 add r2, r1, #2
920: e1520005 cmp r2, r5
924: ba000058 blt a8c <ath_cmn_process_fft+0x338>
928: e1510005 cmp r1, r5
92c: aa000092 bge b7c <ath_cmn_process_fft+0x428>
930: e5d7001f ldrb r0, [r7, #31]
934: e5d71020 ldrb r1, [r7, #32]
938: e1500001 cmp r0, r1
93c: 1a000052 bne a8c <ath_cmn_process_fft+0x338>
940: e58d3040 str r3, [sp, #64] ; 0x40
944: e1a01004 mov r1, r4
948: e59d3044 ldr r3, [sp, #68] ; 0x44
94c: e1a0000b mov r0, fp
950: e58d203c str r2, [sp, #60] ; 0x3c
954: e12fff33 blx r3
958: e3500000 cmp r0, #0
95c: e59d203c ldr r2, [sp, #60] ; 0x3c
960: e59d3040 ldr r3, [sp, #64] ; 0x40
964: 1a00008e bne ba4 <ath_cmn_process_fft+0x450>
968: e59d2010 ldr r2, [sp, #16]
96c: e152000a cmp r2, sl
970: da0000c9 ble c9c <ath_cmn_process_fft+0x548>
974: e59d9028 ldr r9, [sp, #40] ; 0x28
978: e2842001 add r2, r4, #1
97c: e0867002 add r7, r6, r2
980: e3590000 cmp r9, #0
984: 13a09000 movne r9, #0
988: 1a000003 bne 99c <ath_cmn_process_fft+0x248>
98c: e59d2020 ldr r2, [sp, #32]
990: e2425002 sub r5, r2, #2
994: e0844005 add r4, r4, r5
998: e2842001 add r2, r4, #1
99c: e1a04002 mov r4, r2
9a0: e59d2014 ldr r2, [sp, #20]
9a4: e1540002 cmp r4, r2
9a8: aa000037 bge a8c <ath_cmn_process_fft+0x338>
9ac: e59d2010 ldr r2, [sp, #16]
9b0: e152000a cmp r2, sl
9b4: e7d62004 ldrb r2, [r6, r4]
9b8: daffffce ble 8f8 <ath_cmn_process_fft+0x1a4>
9bc: e3520007 cmp r2, #7
9c0: e2855001 add r5, r5, #1
9c4: e086b004 add fp, r6, r4
9c8: 8a000002 bhi 9d8 <ath_cmn_process_fft+0x284>
9cc: e59d202c ldr r2, [sp, #44] ; 0x2c
9d0: e1550002 cmp r5, r2
9d4: aaffffcf bge 918 <ath_cmn_process_fft+0x1c4>
9d8: e3590000 cmp r9, #0
9dc: 0affffed beq 998 <ath_cmn_process_fft+0x244>
9e0: e59d201c ldr r2, [sp, #28]
9e4: e1520005 cmp r2, r5
9e8: 1affffe1 bne 974 <ath_cmn_process_fft+0x220>
9ec: ea00007e b bec <ath_cmn_process_fft+0x498>
9f0: e597e000 ldr lr, [r7]
9f4: e24b201f sub r2, fp, #31
9f8: e597c004 ldr ip, [r7, #4]
9fc: e2871021 add r1, r7, #33 ; 0x21
a00: e5973008 ldr r3, [r7, #8]
a04: e28d0068 add r0, sp, #104 ; 0x68
a08: e58de049 str lr, [sp, #73] ; 0x49
a0c: e58dc04d str ip, [sp, #77] ; 0x4d
a10: e597e010 ldr lr, [r7, #16]
a14: e597c014 ldr ip, [r7, #20]
a18: e58d3051 str r3, [sp, #81] ; 0x51
a1c: e597300c ldr r3, [r7, #12]
a20: e58de059 str lr, [sp, #89] ; 0x59
a24: e58dc05d str ip, [sp, #93] ; 0x5d
a28: e58d3055 str r3, [sp, #85] ; 0x55
a2c: e1d7c1bc ldrh ip, [r7, #28]
a30: e5973018 ldr r3, [r7, #24]
a34: e5d7e01f ldrb lr, [r7, #31]
a38: e1cdc6b5 strh ip, [sp, #101] ; 0x65
a3c: e58d3061 str r3, [sp, #97] ; 0x61
a40: e5cde067 strb lr, [sp, #103] ; 0x67
a44: ebfffffe bl 0 <memcpy>
a48: e59d3038 ldr r3, [sp, #56] ; 0x38
a4c: e59d1024 ldr r1, [sp, #36] ; 0x24
a50: e59d0018 ldr r0, [sp, #24]
a54: e58d300c str r3, [sp, #12]
a58: e59d3030 ldr r3, [sp, #48] ; 0x30
a5c: e58d3008 str r3, [sp, #8]
a60: e1cd2fd8 ldrd r2, [sp, #248] ; 0xf8
a64: e1cd20f0 strd r2, [sp]
a68: e28d2049 add r2, sp, #73 ; 0x49
a6c: e59d3034 ldr r3, [sp, #52] ; 0x34
a70: e12fff33 blx r3
a74: e3a01087 mov r1, #135 ; 0x87
a78: e28d0049 add r0, sp, #73 ; 0x49
a7c: ebfffffe bl 0 <__memzero>
a80: e59d1020 ldr r1, [sp, #32]
a84: e28d0049 add r0, sp, #73 ; 0x49
a88: ebfffffe bl 0 <add_device_randomness>
a8c: e3a00001 mov r0, #1
a90: e28dd0d4 add sp, sp, #212 ; 0xd4
a94: e8bd8ff0 pop {r4, r5, r6, r7, r8, r9, sl, fp, pc}
a98: e58d3038 str r3, [sp, #56] ; 0x38
a9c: e3003000 movw r3, #0
aa0: e3002000 movw r2, #0
aa4: e3403000 movt r3, #0
aa8: e3402000 movt r2, #0
aac: e58d3034 str r3, [sp, #52] ; 0x34
ab0: e3a0b03c mov fp, #60 ; 0x3c
ab4: e3a03038 mov r3, #56 ; 0x38
ab8: e58d2044 str r2, [sp, #68] ; 0x44
abc: e3a0a03f mov sl, #63 ; 0x3f
ac0: e58d3020 str r3, [sp, #32]
ac4: eaffff7a b 8b4 <ath_cmn_process_fft+0x160>
ac8: e59db01c ldr fp, [sp, #28]
acc: e153000b cmp r3, fp
ad0: 0a00005e beq c50 <ath_cmn_process_fft+0x4fc>
ad4: e06b5005 rsb r5, fp, r5
ad8: e2855001 add r5, r5, #1
adc: e3550003 cmp r5, #3
ae0: 979ff105 ldrls pc, [pc, r5, lsl #2]
ae4: eaffffd7 b a48 <ath_cmn_process_fft+0x2f4>
ae8: 00000b0c andeq r0, r0, ip, lsl #22
aec: 00000af8 strdeq r0, [r0], -r8
af0: 00000b20 andeq r0, r0, r0, lsr #22
af4: 000009f0 strdeq r0, [r0], -r0 ; <UNPREDICTABLE>
af8: e1a0200b mov r2, fp
afc: e1a01007 mov r1, r7
b00: e28d0049 add r0, sp, #73 ; 0x49
b04: ebfffffe bl 0 <memcpy>
b08: eaffffce b a48 <ath_cmn_process_fft+0x2f4>
b0c: e24b2001 sub r2, fp, #1
b10: e1a01007 mov r1, r7
b14: e28d004a add r0, sp, #74 ; 0x4a
b18: ebfffffe bl 0 <memcpy>
b1c: eaffffc9 b a48 <ath_cmn_process_fft+0x2f4>
b20: e597e000 ldr lr, [r7]
b24: e24b2020 sub r2, fp, #32
b28: e597c004 ldr ip, [r7, #4]
b2c: e2871021 add r1, r7, #33 ; 0x21
b30: e5973008 ldr r3, [r7, #8]
b34: e28d0069 add r0, sp, #105 ; 0x69
b38: e58de04a str lr, [sp, #74] ; 0x4a
b3c: e58dc04e str ip, [sp, #78] ; 0x4e
b40: e597e010 ldr lr, [r7, #16]
b44: e597c014 ldr ip, [r7, #20]
b48: e58d3052 str r3, [sp, #82] ; 0x52
b4c: e597300c ldr r3, [r7, #12]
b50: e58de05a str lr, [sp, #90] ; 0x5a
b54: e58dc05e str ip, [sp, #94] ; 0x5e
b58: e5d7e01f ldrb lr, [r7, #31]
b5c: e1d7c1bc ldrh ip, [r7, #28]
b60: e58d3056 str r3, [sp, #86] ; 0x56
b64: e5973018 ldr r3, [r7, #24]
b68: e1cdc6b6 strh ip, [sp, #102] ; 0x66
b6c: e5cde068 strb lr, [sp, #104] ; 0x68
b70: e58d3062 str r3, [sp, #98] ; 0x62
b74: ebfffffe bl 0 <memcpy>
b78: eaffffb2 b a48 <ath_cmn_process_fft+0x2f4>
b7c: e58d3040 str r3, [sp, #64] ; 0x40
b80: e1a01004 mov r1, r4
b84: e59d3044 ldr r3, [sp, #68] ; 0x44
b88: e1a0000b mov r0, fp
b8c: e58d203c str r2, [sp, #60] ; 0x3c
b90: e12fff33 blx r3
b94: e3500000 cmp r0, #0
b98: e59d203c ldr r2, [sp, #60] ; 0x3c
b9c: e59d3040 ldr r3, [sp, #64] ; 0x40
ba0: 0a00000e beq be0 <ath_cmn_process_fft+0x48c>
ba4: e5d7101f ldrb r1, [r7, #31]
ba8: e5d70020 ldrb r0, [r7, #32]
bac: e59dc01c ldr ip, [sp, #28]
bb0: e15c0005 cmp ip, r5
bb4: d1510000 cmple r1, r0
bb8: 03a01001 moveq r1, #1
bbc: 13a01000 movne r1, #0
bc0: e1520005 cmp r2, r5
bc4: d3a02000 movle r2, #0
bc8: c2012001 andgt r2, r1, #1
bcc: e3520000 cmp r2, #0
bd0: 0a00001a beq c40 <ath_cmn_process_fft+0x4ec>
bd4: e5db2001 ldrb r2, [fp, #1]
bd8: e3520007 cmp r2, #7
bdc: 9affff6d bls 998 <ath_cmn_process_fft+0x244>
be0: e59d201c ldr r2, [sp, #28]
be4: e1520005 cmp r2, r5
be8: 1affff5e bne 968 <ath_cmn_process_fft+0x214>
bec: e58d303c str r3, [sp, #60] ; 0x3c
bf0: e1a02007 mov r2, r7
bf4: e59d3038 ldr r3, [sp, #56] ; 0x38
bf8: e1cd8fd8 ldrd r8, [sp, #248] ; 0xf8
bfc: e59d1024 ldr r1, [sp, #36] ; 0x24
c00: e58d300c str r3, [sp, #12]
c04: e59d3030 ldr r3, [sp, #48] ; 0x30
c08: e1cd80f0 strd r8, [sp]
c0c: e59d0018 ldr r0, [sp, #24]
c10: e58d3008 str r3, [sp, #8]
c14: e59d3034 ldr r3, [sp, #52] ; 0x34
c18: e12fff33 blx r3
c1c: e58d0028 str r0, [sp, #40] ; 0x28
c20: e1a00007 mov r0, r7
c24: e59d1020 ldr r1, [sp, #32]
c28: ebfffffe bl 0 <add_device_randomness>
c2c: e59d3010 ldr r3, [sp, #16]
c30: e153000a cmp r3, sl
c34: e59d303c ldr r3, [sp, #60] ; 0x3c
c38: caffff4d bgt 974 <ath_cmn_process_fft+0x220>
c3c: eaffff92 b a8c <ath_cmn_process_fft+0x338>
c40: e59d202c ldr r2, [sp, #44] ; 0x2c
c44: e1520005 cmp r2, r5
c48: 1affffe4 bne be0 <ath_cmn_process_fft+0x48c>
c4c: eaffffe0 b bd4 <ath_cmn_process_fft+0x480>
c50: e59d3038 ldr r3, [sp, #56] ; 0x38
c54: e59d1024 ldr r1, [sp, #36] ; 0x24
c58: e59d0018 ldr r0, [sp, #24]
c5c: e58d300c str r3, [sp, #12]
c60: e59d3030 ldr r3, [sp, #48] ; 0x30
c64: e58d3008 str r3, [sp, #8]
c68: e1cd2fd8 ldrd r2, [sp, #248] ; 0xf8
c6c: e1cd20f0 strd r2, [sp]
c70: e1a02007 mov r2, r7
c74: e59d3034 ldr r3, [sp, #52] ; 0x34
c78: e12fff33 blx r3
c7c: e1a00007 mov r0, r7
c80: e59d1020 ldr r1, [sp, #32]
c84: ebfffffe bl 0 <add_device_randomness>
c88: e3a00001 mov r0, #1
c8c: eaffff7f b a90 <ath_cmn_process_fft+0x33c>
c90: e59d201c ldr r2, [sp, #28]
c94: e1530002 cmp r3, r2
c98: 0affffd3 beq bec <ath_cmn_process_fft+0x498>
c9c: e59db01c ldr fp, [sp, #28]
ca0: eaffff8b b ad4 <ath_cmn_process_fft+0x380>
ca4: e3000000 movw r0, #0
ca8: e300119a movw r1, #410 ; 0x19a
cac: e3400000 movt r0, #0
cb0: e3a03000 mov r3, #0
cb4: e58d3038 str r3, [sp, #56] ; 0x38
cb8: ebfffffe bl 0 <warn_slowpath_null>
cbc: eaffff76 b a9c <ath_cmn_process_fft+0x348>
cc0: e3a03000 mov r3, #0
cc4: e58d3038 str r3, [sp, #56] ; 0x38
cc8: eaffff73 b a9c <ath_cmn_process_fft+0x348>
