https://github.com/torvalds/linux
Revision a73914c35b05d80f8ce78288e10056c91090b666 authored by Mark Salyzyn on 22 September 2011, 15:32:23 UTC, committed by James Bottomley on 02 October 2011, 18:28:55 UTC
When a wide port is being utilized to a target, if one disables only one
of the
phys, we get an OS crash:

BUG: unable to handle kernel NULL pointer dereference at
0000000000000238
IP: [<ffffffff814ca9b1>] mutex_lock+0x21/0x50
PGD 4103f5067 PUD 41dba9067 PMD 0
Oops: 0002 [#1] SMP
last sysfs file: /sys/bus/pci/slots/5/address
CPU 0
Modules linked in: pm8001(U) ses enclosure fuse nfsd exportfs autofs4
ipmi_devintf ipmi_si ipmi_msghandler nfs lockd fscache nfs_acl
auth_rpcgss 8021q fcoe libfcoe garp libfc scsi_transport_fc stp scsi_tgt
llc sunrpc cpufreq_ondemand acpi_cpufreq freq_table ipv6 sr_mod cdrom
dm_mirror dm_region_hash dm_log uinput sg i2c_i801 i2c_core iTCO_wdt
iTCO_vendor_support e1000e mlx4_ib ib_mad ib_core mlx4_en mlx4_core ext3
jbd mbcache sd_mod crc_t10dif usb_storage ata_generic pata_acpi ata_piix
libsas(U) scsi_transport_sas dm_mod [last unloaded: pm8001]

Modules linked in: pm8001(U) ses enclosure fuse nfsd exportfs autofs4
ipmi_devintf ipmi_si ipmi_msghandler nfs lockd fscache nfs_acl
auth_rpcgss 8021q fcoe libfcoe garp libfc scsi_transport_fc stp scsi_tgt
llc sunrpc cpufreq_ondemand acpi_cpufreq freq_table ipv6 sr_mod cdrom
dm_mirror dm_region_hash dm_log uinput sg i2c_i801 i2c_core iTCO_wdt
iTCO_vendor_support e1000e mlx4_ib ib_mad ib_core mlx4_en mlx4_core ext3
jbd mbcache sd_mod crc_t10dif usb_storage ata_generic pata_acpi ata_piix
libsas(U) scsi_transport_sas dm_mod [last unloaded: pm8001]
Pid: 5146, comm: scsi_wq_5 Not tainted
2.6.32-71.29.1.el6.lustre.7.x86_64 #1 Storage Server
RIP: 0010:[<ffffffff814ca9b1>]  [<ffffffff814ca9b1>]
mutex_lock+0x21/0x50
RSP: 0018:ffff8803e4e33d30  EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000238 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8803e664c800 RDI: 0000000000000238
RBP: ffff8803e4e33d40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000238 R14: ffff88041acb7200 R15: ffff88041c51ada0
FS:  0000000000000000(0000) GS:ffff880028200000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 0000000000000238 CR3: 0000000410143000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process scsi_wq_5 (pid: 5146, threadinfo ffff8803e4e32000, task
ffff8803e4e294a0)
Stack:
 ffff8803e664c800 0000000000000000 ffff8803e4e33d70 ffffffffa001f06e
<0> ffff8803e4e33d60 ffff88041c51ada0 ffff88041acb7200 ffff88041bc0aa00
<0> ffff8803e4e33d90 ffffffffa0032b6c 0000000000000014 ffff88041acb7200
Call Trace:
 [<ffffffffa001f06e>] sas_port_delete_phy+0x2e/0xa0 [scsi_transport_sas]
 [<ffffffffa0032b6c>] sas_unregister_devs_sas_addr+0xac/0xe0 [libsas]
 [<ffffffffa0034914>] sas_ex_revalidate_domain+0x204/0x330 [libsas]
 [<ffffffffa00307f0>] ? sas_revalidate_domain+0x0/0x90 [libsas]
 [<ffffffffa0030855>] sas_revalidate_domain+0x65/0x90 [libsas]
 [<ffffffff8108c7d0>] worker_thread+0x170/0x2a0
 [<ffffffff81091ea0>] ? autoremove_wake_function+0x0/0x40
 [<ffffffff8108c660>] ? worker_thread+0x0/0x2a0
 [<ffffffff81091b36>] kthread+0x96/0xa0
 [<ffffffff810141ca>] child_rip+0xa/0x20
 [<ffffffff81091aa0>] ? kthread+0x0/0xa0
 [<ffffffff810141c0>] ? child_rip+0x0/0x20
Code: ff ff 85 c0 75 ed eb d6 66 90 55 48 89 e5 48 83 ec 10 48 89 1c 24
4c 89 64 24 08 0f 1f 44 00 00 48 89 fb e8 92 f4 ff ff 48 89 df <f0> ff
0f 79 05 e8 25 00 00 00 65 48 8b 04 25 08 cc 00 00 48 2d
RIP  [<ffffffff814ca9b1>] mutex_lock+0x21/0x50
 RSP <ffff8803e4e33d30>
CR2: 0000000000000238

The following patch is admittedly a band-aid, and does not solve the
root cause, but it still is a good candidate for hardening as a pointer
check before reference.

Signed-off-by: Mark Salyzyn <mark_salyzyn@us.xyratex.com>
Tested-by: Jack Wang <jack_wang@usish.com>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
1 parent 9bfacd0
Raw File
Tip revision: a73914c35b05d80f8ce78288e10056c91090b666 authored by Mark Salyzyn on 22 September 2011, 15:32:23 UTC
[SCSI] libsas: fix panic when single phy is disabled on a wide port
Tip revision: a73914c
Makefile.headersinst
# ==========================================================================
# Installing headers
#
# header-y  - list files to be installed. They are preprocessed
#             to remove __KERNEL__ section of the file
# objhdr-y  - Same as header-y but for generated files
#
# ==========================================================================

# called may set destination dir (when installing to asm/)
_dst := $(if $(dst),$(dst),$(obj))

kbuild-file := $(srctree)/$(obj)/Kbuild
include $(kbuild-file)

_dst := $(if $(destination-y),$(destination-y),$(_dst))

include scripts/Kbuild.include

install       := $(INSTALL_HDR_PATH)/$(_dst)

header-y      := $(sort $(header-y))
subdirs       := $(patsubst %/,%,$(filter %/, $(header-y)))
header-y      := $(filter-out %/, $(header-y))

# files used to track state of install/check
install-file  := $(install)/.install
check-file    := $(install)/.check

# generic-y list all files an architecture uses from asm-generic
# Use this to build a list of headers which require a wrapper
wrapper-files := $(filter $(header-y), $(generic-y))

# all headers files for this dir
header-y      := $(filter-out $(generic-y), $(header-y))
all-files     := $(header-y) $(objhdr-y) $(wrapper-files)
input-files   := $(addprefix $(srctree)/$(obj)/,$(header-y)) \
                 $(addprefix $(objtree)/$(obj)/,$(objhdr-y))
output-files  := $(addprefix $(install)/, $(all-files))

# Work out what needs to be removed
oldheaders    := $(patsubst $(install)/%,%,$(wildcard $(install)/*.h))
unwanted      := $(filter-out $(all-files),$(oldheaders))

# Prefix unwanted with full paths to $(INSTALL_HDR_PATH)
unwanted-file := $(addprefix $(install)/, $(unwanted))

printdir = $(patsubst $(INSTALL_HDR_PATH)/%/,%,$(dir $@))

quiet_cmd_install = INSTALL $(printdir) ($(words $(all-files))\
                            file$(if $(word 2, $(all-files)),s))
      cmd_install = \
        $(PERL) $< $(srctree)/$(obj) $(install) $(SRCARCH) $(header-y); \
        $(PERL) $< $(objtree)/$(obj) $(install) $(SRCARCH) $(objhdr-y); \
        for F in $(wrapper-files); do                                   \
                echo "\#include <asm-generic/$$F>" > $(install)/$$F;    \
        done;                                                           \
        touch $@

quiet_cmd_remove = REMOVE  $(unwanted)
      cmd_remove = rm -f $(unwanted-file)

quiet_cmd_check = CHECK   $(printdir) ($(words $(all-files)) files)
# Headers list can be pretty long, xargs helps to avoid
# the "Argument list too long" error.
      cmd_check = for f in $(all-files); do                          \
                  echo "$(install)/$${f}"; done                      \
                  | xargs                                            \
                  $(PERL) $< $(INSTALL_HDR_PATH)/include $(SRCARCH); \
	          touch $@

PHONY += __headersinst __headerscheck

ifndef HDRCHECK
# Rules for installing headers
__headersinst: $(subdirs) $(install-file)
	@:

targets += $(install-file)
$(install-file): scripts/headers_install.pl $(input-files) FORCE
	$(if $(unwanted),$(call cmd,remove),)
	$(if $(wildcard $(dir $@)),,$(shell mkdir -p $(dir $@)))
	$(call if_changed,install)

else
__headerscheck: $(subdirs) $(check-file)
	@:

targets += $(check-file)
$(check-file): scripts/headers_check.pl $(output-files) FORCE
	$(call if_changed,check)

endif

# Recursion
hdr-inst := -rR -f $(srctree)/scripts/Makefile.headersinst obj
.PHONY: $(subdirs)
$(subdirs):
	$(Q)$(MAKE) $(hdr-inst)=$(obj)/$@ dst=$(_dst)/$@

targets := $(wildcard $(sort $(targets)))
cmd_files := $(wildcard \
             $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))

ifneq ($(cmd_files),)
	include $(cmd_files)
endif

.PHONY: $(PHONY)
PHONY += FORCE
FORCE: ;
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