ci2 starts bisection 2024-04-06 15:19:39.530777672 +0000 UTC m=+48027.488591099
bisecting fixing commit since 05ef4ccb57746f921003b9340fc2f0532c177f41
building syzkaller on 3222d10cbe77bbedb5a7c455e5bcb6b7081a63b7
ensuring issue is reproducible on original commit 05ef4ccb57746f921003b9340fc2f0532c177f41

testing commit 05ef4ccb57746f921003b9340fc2f0532c177f41 gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 832a549a37b7f0ed93c6682b234401adf984519f40d7a703df783b00583bd675
all runs: crashed: KASAN: use-after-free Read in jbd2_journal_get_write_access
representative crash: KASAN: use-after-free Read in jbd2_journal_get_write_access, types: [KASAN]
check whether we can drop unnecessary instrumentation
disabling configs for [ATOMIC_SLEEP HANG LEAK UBSAN BUG LOCKDEP], they are not needed
testing commit 05ef4ccb57746f921003b9340fc2f0532c177f41 gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 251427a4672903464d3d4f09433de7f0afc0bd9934c6c41a6866fb286bee9bfb
all runs: crashed: KASAN: use-after-free Read in jbd2_journal_get_write_access
representative crash: KASAN: use-after-free Read in jbd2_journal_get_write_access, types: [KASAN]
the bug reproduces without the instrumentation
disabling configs for [LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN BUG], they are not needed
kconfig minimization: base=4920 full=6161 leaves diff=241
split chunks (needed=false): <241>
split chunk #0 of len 241 into 5 parts
testing without sub-chunk 1/5
disabling configs for [BUG LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN], they are not needed
testing commit 05ef4ccb57746f921003b9340fc2f0532c177f41 gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 6711c752cbba008bdc3a0b391cfbea32d3fbb295371e06d6e963e43d4c6dfc08
all runs: crashed: KASAN: use-after-free Read in jbd2_journal_get_write_access
representative crash: KASAN: use-after-free Read in jbd2_journal_get_write_access, types: [KASAN]
the chunk can be dropped
testing without sub-chunk 2/5
disabling configs for [ATOMIC_SLEEP HANG LEAK UBSAN BUG LOCKDEP], they are not needed
testing commit 05ef4ccb57746f921003b9340fc2f0532c177f41 gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: cdb3c61db472da89ef1406e2ca3f575e9320e2a6b32bf5f6cc274eff7af7ae15
all runs: crashed: KASAN: use-after-free Read in jbd2_journal_get_write_access
representative crash: KASAN: use-after-free Read in jbd2_journal_get_write_access, types: [KASAN]
the chunk can be dropped
testing without sub-chunk 3/5
disabling configs for [ATOMIC_SLEEP HANG LEAK UBSAN BUG LOCKDEP], they are not needed
testing commit 05ef4ccb57746f921003b9340fc2f0532c177f41 gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 0f9711902b451f2e94c19da2fb34b9d1a3af07684e8aaec53c327e315611cd18
all runs: crashed: KASAN: use-after-free Read in jbd2_journal_get_write_access
representative crash: KASAN: use-after-free Read in jbd2_journal_get_write_access, types: [KASAN]
the chunk can be dropped
testing without sub-chunk 4/5
disabling configs for [LEAK UBSAN BUG LOCKDEP ATOMIC_SLEEP HANG], they are not needed
testing commit 05ef4ccb57746f921003b9340fc2f0532c177f41 gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: d180c2f5e63a0f0cdb5fa5d29741bbce10a6f9b32cdf87b983fbc7627b51f51d
all runs: crashed: KASAN: use-after-free Read in jbd2_journal_get_write_access
representative crash: KASAN: use-after-free Read in jbd2_journal_get_write_access, types: [KASAN]
the chunk can be dropped
testing without sub-chunk 5/5
disabling configs for [BUG LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN], they are not needed
testing commit 05ef4ccb57746f921003b9340fc2f0532c177f41 gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
failed building 05ef4ccb57746f921003b9340fc2f0532c177f41: net/socket.c:1189: undefined reference to `wext_handle_ioctl'
net/socket.c:3383: undefined reference to `compat_wext_handle_ioctl'
net/core/net-procfs.c:343: undefined reference to `wext_proc_exit'
net/core/net-procfs.c:327: undefined reference to `wext_proc_init'
minimized to 45 configs; suspects: [HID_ZEROPLUS USB_NET_MCS7830 USB_NET_NET1080 USB_NET_PLUSB USB_NET_RNDIS_HOST USB_NET_SMSC75XX USB_NET_SMSC95XX USB_NET_SR9700 USB_NET_SR9800 USB_NET_ZAURUS USB_OHCI_HCD USB_OHCI_HCD_PCI USB_OHCI_HCD_PLATFORM USB_OTG USB_OTG_FSM USB_PRINTER USB_SERIAL USB_SERIAL_FTDI_SIO USB_SERIAL_GENERIC USB_SERIAL_PL2303 USB_STORAGE_ALAUDA USB_STORAGE_CYPRESS_ATACB USB_STORAGE_DATAFAB USB_STORAGE_FREECOM USB_STORAGE_ISD200 USB_STORAGE_JUMPSHOT USB_STORAGE_KARMA USB_STORAGE_ONETOUCH USB_STORAGE_SDDR09 USB_STORAGE_SDDR55 USB_STORAGE_USBAT USB_TRANCEVIBRATOR USB_U_AUDIO USB_U_ETHER USB_U_SERIAL USB_WDM WLAN WLAN_VENDOR_ATH WLAN_VENDOR_ATMEL WLAN_VENDOR_BROADCOM WLAN_VENDOR_INTERSIL WLAN_VENDOR_MARVELL WLAN_VENDOR_MEDIATEK WLAN_VENDOR_MICROCHIP WLAN_VENDOR_RALINK WLAN_VENDOR_REALTEK WLAN_VENDOR_RSI WLAN_VENDOR_ZYDAS X86_X32 ZEROPLUS_FF]
disabling configs for [HANG LEAK UBSAN BUG LOCKDEP ATOMIC_SLEEP], they are not needed
testing current HEAD 993bed180178156a70afdafe8aaf23a117107352
testing commit 993bed180178156a70afdafe8aaf23a117107352 gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 0c169033b93ccd4b861fd18d1589707ef3e2143a165af0e8ebdf0d3109fc6ccf
all runs: crashed: KASAN: use-after-free Read in jbd2_journal_get_write_access
representative crash: KASAN: use-after-free Read in jbd2_journal_get_write_access, types: [KASAN]
crash still not fixed/happens on the oldest tested release
revisions tested: 7, total time: 3h44m10.399231132s (build: 2h28m15.072153073s, test: 1h14m6.095323858s)
crash still not fixed or there were kernel test errors
commit msg: Merge "Merge branch 'android13-5.15' into branch 'android13-5.15-lts'" into android13-5.15-lts
crash: KASAN: use-after-free Read in jbd2_journal_get_write_access
RBP: 00007fb5c9870120 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 000000000000000b R14: 00007fb5c9e0cf80 R15: 00007ffe27a7ce18
 </TASK>
==================================================================
BUG: KASAN: use-after-free in is_handle_aborted include/linux/jbd2.h:1694 [inline]
BUG: KASAN: use-after-free in jbd2_journal_get_write_access+0x10f/0x140 fs/jbd2/transaction.c:1241
Read of size 1 at addr ffff88811f543cdc by task syz-executor.2/425

CPU: 0 PID: 425 Comm: syz-executor.2 Not tainted 5.15.148-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x38/0x49 lib/dump_stack.c:106
 print_address_description.constprop.0+0x24/0x160 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report.cold+0x82/0xdb mm/kasan/report.c:444
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306
 is_handle_aborted include/linux/jbd2.h:1694 [inline]
 jbd2_journal_get_write_access+0x10f/0x140 fs/jbd2/transaction.c:1241
 __ext4_journal_get_write_access+0x17c/0x3c0 fs/ext4/ext4_jbd2.c:235
 ext4_reserve_inode_write+0x157/0x220 fs/ext4/inode.c:5813
 __ext4_mark_inode_dirty+0x10d/0x660 fs/ext4/inode.c:5987
 ext4_symlink+0x82f/0xd40 fs/ext4/namei.c:3463
 vfs_symlink fs/namei.c:4435 [inline]
 vfs_symlink+0xe9/0x2b0 fs/namei.c:4420
 do_symlinkat+0x134/0x2a0 fs/namei.c:4464
 __do_sys_symlink fs/namei.c:4486 [inline]
 __se_sys_symlink fs/namei.c:4484 [inline]
 __x64_sys_symlink+0x75/0x90 fs/namei.c:4484
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fb5c9cedba9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb5c98700c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007fb5c9e0cf80 RCX: 00007fb5c9cedba9
RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000020000140
RBP: 00007fb5c9870120 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 000000000000000b R14: 00007fb5c9e0cf80 R15: 00007ffe27a7ce18
 </TASK>

Allocated by task 425:
 kasan_save_stack+0x26/0x50 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:433 [inline]
 __kasan_slab_alloc+0x94/0xc0 mm/kasan/common.c:466
 kasan_slab_alloc include/linux/kasan.h:217 [inline]
 slab_post_alloc_hook mm/slab.h:550 [inline]
 slab_alloc_node mm/slub.c:3240 [inline]
 slab_alloc mm/slub.c:3248 [inline]
 kmem_cache_alloc+0x197/0x480 mm/slub.c:3253
 kmem_cache_zalloc include/linux/slab.h:723 [inline]
 jbd2_alloc_handle include/linux/jbd2.h:1597 [inline]
 new_handle fs/jbd2/transaction.c:477 [inline]
 jbd2__journal_start+0x16f/0x790 fs/jbd2/transaction.c:504
 __ext4_journal_start_sb+0x237/0x2d0 fs/ext4/ext4_jbd2.c:105
 __ext4_new_inode+0x24bc/0x4250 fs/ext4/ialloc.c:1080
 ext4_symlink+0x361/0xd40 fs/ext4/namei.c:3382
 vfs_symlink fs/namei.c:4435 [inline]
 vfs_symlink+0xe9/0x2b0 fs/namei.c:4420
 do_symlinkat+0x134/0x2a0 fs/namei.c:4464
 __do_sys_symlink fs/namei.c:4486 [inline]
 __se_sys_symlink fs/namei.c:4484 [inline]
 __x64_sys_symlink+0x75/0x90 fs/namei.c:4484
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Freed by task 425:
 kasan_save_stack+0x26/0x50 mm/kasan/common.c:38
 kasan_set_track+0x25/0x30 mm/kasan/common.c:45
 kasan_set_free_info+0x24/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free mm/kasan/common.c:365 [inline]
 ____kasan_slab_free mm/kasan/common.c:327 [inline]
 __kasan_slab_free+0x111/0x150 mm/kasan/common.c:373
 kasan_slab_free include/linux/kasan.h:193 [inline]
 slab_free_hook mm/slub.c:1723 [inline]
 slab_free_freelist_hook+0x94/0x1a0 mm/slub.c:1749
 slab_free mm/slub.c:3519 [inline]
 kmem_cache_free+0x105/0x250 mm/slub.c:3535
 jbd2_free_handle include/linux/jbd2.h:1602 [inline]
 jbd2_journal_stop+0x496/0xf70 fs/jbd2/transaction.c:1964
 __ext4_journal_stop+0xc4/0x1a0 fs/ext4/ext4_jbd2.c:127
 ext4_symlink+0x7fc/0xd40 fs/ext4/namei.c:3461
 vfs_symlink fs/namei.c:4435 [inline]
 vfs_symlink+0xe9/0x2b0 fs/namei.c:4420
 do_symlinkat+0x134/0x2a0 fs/namei.c:4464
 __do_sys_symlink fs/namei.c:4486 [inline]
 __se_sys_symlink fs/namei.c:4484 [inline]
 __x64_sys_symlink+0x75/0x90 fs/namei.c:4484
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

The buggy address belongs to the object at ffff88811f543cb8
 which belongs to the cache jbd2_journal_handle of size 56
The buggy address is located 36 bytes inside of
 56-byte region [ffff88811f543cb8, ffff88811f543cf0)
The buggy address belongs to the page:
page:ffffea00047d50c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11f543
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 0000000000000000 dead000000000122 ffff88810538be00
raw: 0000000000000000 00000000802e002e 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Reclaimable, gfp_mask 0x112c50(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 359, ts 53882054681, free_ts 0
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook mm/page_alloc.c:2604 [inline]
 prep_new_page+0x1a2/0x310 mm/page_alloc.c:2610
 get_page_from_freelist+0x1ce2/0x30a0 mm/page_alloc.c:4484
 __alloc_pages+0x2d1/0x2620 mm/page_alloc.c:5776
 __alloc_pages_node include/linux/gfp.h:591 [inline]
 alloc_pages_node include/linux/gfp.h:605 [inline]
 alloc_pages include/linux/gfp.h:618 [inline]
 alloc_slab_page mm/slub.c:1793 [inline]
 allocate_slab+0x39d/0x530 mm/slub.c:1932
 new_slab mm/slub.c:1995 [inline]
 ___slab_alloc.constprop.0+0x3ca/0x890 mm/slub.c:3028
 __slab_alloc.constprop.0+0x42/0x80 mm/slub.c:3115
 slab_alloc_node mm/slub.c:3206 [inline]
 slab_alloc mm/slub.c:3248 [inline]
 kmem_cache_alloc+0x440/0x480 mm/slub.c:3253
 kmem_cache_zalloc include/linux/slab.h:723 [inline]
 jbd2_alloc_handle include/linux/jbd2.h:1597 [inline]
 new_handle fs/jbd2/transaction.c:477 [inline]
 jbd2__journal_start+0x16f/0x790 fs/jbd2/transaction.c:504
 __ext4_journal_start_sb+0x237/0x2d0 fs/ext4/ext4_jbd2.c:105
 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
 ext4_dirty_inode+0x9c/0x100 fs/ext4/inode.c:6021
 __mark_inode_dirty+0xd7/0x830 fs/fs-writeback.c:2464
 generic_update_time fs/inode.c:1817 [inline]
 inode_update_time fs/inode.c:1830 [inline]
 touch_atime+0x450/0x520 fs/inode.c:1902
 file_accessed include/linux/fs.h:2551 [inline]
 iterate_dir+0x3c3/0x730 fs/readdir.c:70
 __do_sys_getdents64 fs/readdir.c:369 [inline]
 __se_sys_getdents64 fs/readdir.c:354 [inline]
 __x64_sys_getdents64+0x12f/0x230 fs/readdir.c:354
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88811f543b80: fb fb fc fc fc fc fa fb fb fb fb fb fb fc fc fc
 ffff88811f543c00: fc fa fb fb fb fb fb fb fc fc fc fc fa fb fb fb
>ffff88811f543c80: fb fb fb fc fc fc fc fa fb fb fb fb fb fb fc fc
                                                    ^
 ffff88811f543d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fa fb fb
 ffff88811f543d80: fb fb fb fb fc fc fc fc fa fb fb fb fb fb fb fc
==================================================================
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 425 Comm: syz-executor.2 Tainted: G    B             5.15.148-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:do_get_write_access+0x56f/0xcf0 fs/jbd2/transaction.c:1102
Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 53 07 00 00 49 8b 75 20 48 8b 7d b0 e8 a8 81 02 00 e9 6c fe ff ff 0f 0b <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 89 ca 48 c1 ea 03 80 3c 02
RSP: 0018:ffffc90000a37a78 EFLAGS: 00010286
RAX: ffff88810b734a00 RBX: dffffc0000000000 RCX: ffffffff81d4bf12
RDX: 0000000000000000 RSI: ffff8881248e1000 RDI: ffff8881248e10a0
RBP: ffffc90000a37af8 R08: ffff88810b423d38 R09: ffff88810b423d28
R10: ffffed1023ea2b11 R11: 6d79735f73667620 R12: ffff88810b423d10
R13: ffff88811f515888 R14: ffff88811f543cb8 R15: ffff88810b423d40
FS:  00007fb5c98706c0(0000) GS:ffff8881f7500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd1613f328 CR3: 000000012495d000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 jbd2_journal_get_write_access+0xe3/0x140 fs/jbd2/transaction.c:1251
 __ext4_journal_get_write_access+0x17c/0x3c0 fs/ext4/ext4_jbd2.c:235
 ext4_reserve_inode_write+0x157/0x220 fs/ext4/inode.c:5813
 __ext4_mark_inode_dirty+0x10d/0x660 fs/ext4/inode.c:5987
 ext4_symlink+0x82f/0xd40 fs/ext4/namei.c:3463
 vfs_symlink fs/namei.c:4435 [inline]
 vfs_symlink+0xe9/0x2b0 fs/namei.c:4420
 do_symlinkat+0x134/0x2a0 fs/namei.c:4464
 __do_sys_symlink fs/namei.c:4486 [inline]
 __se_sys_symlink fs/namei.c:4484 [inline]
 __x64_sys_symlink+0x75/0x90 fs/namei.c:4484
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fb5c9cedba9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb5c98700c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007fb5c9e0cf80 RCX: 00007fb5c9cedba9
RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000020000140
RBP: 00007fb5c9870120 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 000000000000000b R14: 00007fb5c9e0cf80 R15: 00007ffe27a7ce18
 </TASK>
Modules linked in:
---[ end trace 4c8d1d9cddab219a ]---
RIP: 0010:do_get_write_access+0x56f/0xcf0 fs/jbd2/transaction.c:1102
Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 53 07 00 00 49 8b 75 20 48 8b 7d b0 e8 a8 81 02 00 e9 6c fe ff ff 0f 0b <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 89 ca 48 c1 ea 03 80 3c 02
RSP: 0018:ffffc90000a37a78 EFLAGS: 00010286
RAX: ffff88810b734a00 RBX: dffffc0000000000 RCX: ffffffff81d4bf12
RDX: 0000000000000000 RSI: ffff8881248e1000 RDI: ffff8881248e10a0
RBP: ffffc90000a37af8 R08: ffff88810b423d38 R09: ffff88810b423d28
R10: ffffed1023ea2b11 R11: 6d79735f73667620 R12: ffff88810b423d10
R13: ffff88811f515888 R14: ffff88811f543cb8 R15: ffff88810b423d40
FS:  00007fb5c98706c0(0000) GS:ffff8881f7500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd1613f328 CR3: 000000012495d000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400