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From: grog@lemis.de (Greg Lehey)
Organisation: LEMIS, Schellnhausen 2, 36325 Feldatal, Germany
Phone: +49-6637-919123
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	id QAA18767 for hackers@freebsd.org; Tue, 2 Jan 1996 16:17:38 +0100
Message-Id: <199601021517.QAA18767@allegro.lemis.de>
Subject: -current panics: vm_page_free: freeing busy page
To: hackers@freebsd.org (FreeBSD Hackers)
Date: Tue, 2 Jan 1996 16:17:38 +0100 (MET)
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I've had a couple of panics with the latest -current (ctm-cvs 1510).
Here are the stack traces:

(kgdb) bt
#0  boot (howto=256) at ../../i386/i386/machdep.c:928
#1  0xf0118a25 in panic (fmt=0xf01a4f6b "vm_page_free: freeing busy page") at ../../kern/subr_prf.c:124
#2  0xf01a5182 in vm_page_free (mem=0xf026ac94) at ../../vm/vm_page.c:811
#3  0xf012c252 in vm_hold_free_pages (bp=0xf26eb5ec, froma=4080128000, toa=4080136192) at ../../kern/vfs_bio.c:1641
#4  0xf012b09a in allocbuf (bp=0xf26eb5ec, size=0) at ../../kern/vfs_bio.c:1060
#5  0xf012a9ae in getnewbuf (slpflag=0, slptimeo=0, doingvmio=0) at ../../kern/vfs_bio.c:736
#6  0xf012ae4f in getblk (vp=0xf0b3d880, blkno=54, size=8192, slpflag=0, slptimeo=0) at ../../kern/vfs_bio.c:970
#7  0xf0190922 in ffs_balloc (ip=0xf0b50900, bn=54, size=1471, cred=0xf0a2f380, bpp=0xefbffe58, flags=1)
    at ../../ufs/ffs/ffs_balloc.c:261
#8  0xf0193b3d in ffs_write (ap=0xefbffe78) at ../../ufs/ufs/ufs_readwrite.c:255
#9  0xf010e75d in ktrwrite (vp=0xf0b3d880, kth=0xf0b55b00) at ./vnode_if.h:283
#10 0xf010e215 in ktrgenio (vp=0xf0b3d880, fd=3, rw=UIO_READ, iov=0xefbfff1c, len=4096, error=0)
    at ../../kern/kern_ktrace.c:176
#11 0xf0119ec7 in read (p=0xf0b50800, uap=0xefbfff94, retval=0xefbfff8c) at ../../kern/sys_generic.c:121
#12 0xf01b3553 in syscall (frame={tf_es = 39, tf_ds = -272695257, tf_edi = 3, tf_esi = 4096, tf_ebp = -272649188, 
      tf_isp = -272629788, tf_ebx = -272649151, tf_edx = 104, tf_ecx = -272649160, tf_eax = 3, tf_trapno = 0, 
      tf_err = 582, tf_eip = 337569, tf_cs = 31, tf_eflags = 582, tf_esp = -272653320, tf_ss = 39})
    at ../../i386/i386/trap.c:914
#13 0xf01ab6fd in Xsyscall ()

(kgdb) bt
#0  boot (howto=256) at ../../i386/i386/machdep.c:928
#1  0xf0118a25 in panic (fmt=0xf01a4f6b "vm_page_free: freeing busy page") at ../../kern/subr_prf.c:124
#2  0xf01a5182 in vm_page_free (mem=0xf0260770) at ../../vm/vm_page.c:811
#3  0xf012c252 in vm_hold_free_pages (bp=0xf26de0cc, froma=4076064768, toa=4076072960) at ../../kern/vfs_bio.c:1641
#4  0xf012b09a in allocbuf (bp=0xf26de0cc, size=0) at ../../kern/vfs_bio.c:1060
#5  0xf012a9ae in getnewbuf (slpflag=0, slptimeo=0, doingvmio=1) at ../../kern/vfs_bio.c:736
#6  0xf012ae4f in getblk (vp=0xf0a7c500, blkno=0, size=8192, slpflag=0, slptimeo=0) at ../../kern/vfs_bio.c:970
#7  0xf012c92e in cluster_read (vp=0xf0a7c500, filesize=34020, lblkno=0, size=8192, cred=0xffffffff, bpp=0xefbffeb8)
    at ../../kern/vfs_cluster.c:138
#8  0xf0193771 in ffs_read (ap=0xefbffee0) at ../../ufs/ufs/ufs_readwrite.c:123
#9  0xf013396a in vn_read (fp=0xf0b3be40, uio=0xefbfff2c, cred=0xf0b38f00) at ./vnode_if.h:255
#10 0xf0119e77 in read (p=0xf0b2f500, uap=0xefbfff94, retval=0xefbfff8c) at ../../kern/sys_generic.c:114
#11 0xf01b3553 in syscall (frame={tf_es = 39, tf_ds = 39, tf_edi = 134360088, tf_esi = 0, tf_ebp = -272641464, 
      tf_isp = -272629788, tf_ebx = 134316128, tf_edx = 101, tf_ecx = 134360088, tf_eax = 3, tf_trapno = 12, 
      tf_err = 535, tf_eip = 134274309, tf_cs = 31, tf_eflags = 535, tf_esp = -272641544, tf_ss = 39})
    at ../../i386/i386/trap.c:914
#12 0xf01ab6fd in Xsyscall ()

One possible connection: I was using ktrace in both cases.

It would be nice to know which page was suffering from this problem.
Can anybody tell me how to do it?

Greg