)]}'
{
  "log": [
    {
      "commit": "e041c683412d5bf44dc2b109053e3b837b71742d",
      "tree": "9d271066ef379da0c0fb3b8cb4137abd5d2ebba0",
      "parents": [
        "76b81e2b0e2241accebcc68e126bc5ab958661b9"
      ],
      "author": {
        "name": "Alan Stern",
        "email": "stern@rowland.harvard.edu",
        "time": "Mon Mar 27 01:16:30 2006 -0800"
      },
      "committer": {
        "name": "Linus Torvalds",
        "email": "torvalds@g5.osdl.org",
        "time": "Mon Mar 27 08:44:50 2006 -0800"
      },
      "message": "[PATCH] Notifier chain update: API changes\n\nThe kernel\u0027s implementation of notifier chains is unsafe.  There is no\nprotection against entries being added to or removed from a chain while the\nchain is in use.  The issues were discussed in this thread:\n\n    http://marc.theaimsgroup.com/?l\u003dlinux-kernel\u0026m\u003d113018709002036\u0026w\u003d2\n\nWe noticed that notifier chains in the kernel fall into two basic usage\nclasses:\n\n\t\"Blocking\" chains are always called from a process context\n\tand the callout routines are allowed to sleep;\n\n\t\"Atomic\" chains can be called from an atomic context and\n\tthe callout routines are not allowed to sleep.\n\nWe decided to codify this distinction and make it part of the API.  Therefore\nthis set of patches introduces three new, parallel APIs: one for blocking\nnotifiers, one for atomic notifiers, and one for \"raw\" notifiers (which is\nreally just the old API under a new name).  New kinds of data structures are\nused for the heads of the chains, and new routines are defined for\nregistration, unregistration, and calling a chain.  The three APIs are\nexplained in include/linux/notifier.h and their implementation is in\nkernel/sys.c.\n\nWith atomic and blocking chains, the implementation guarantees that the chain\nlinks will not be corrupted and that chain callers will not get messed up by\nentries being added or removed.  For raw chains the implementation provides no\nguarantees at all; users of this API must provide their own protections.  (The\nidea was that situations may come up where the assumptions of the atomic and\nblocking APIs are not appropriate, so it should be possible for users to\nhandle these things in their own way.)\n\nThere are some limitations, which should not be too hard to live with.  For\natomic/blocking chains, registration and unregistration must always be done in\na process context since the chain is protected by a mutex/rwsem.  Also, a\ncallout routine for a non-raw chain must not try to register or unregister\nentries on its own chain.  (This did happen in a couple of places and the code\nhad to be changed to avoid it.)\n\nSince atomic chains may be called from within an NMI handler, they cannot use\nspinlocks for synchronization.  Instead we use RCU.  The overhead falls almost\nentirely in the unregister routine, which is okay since unregistration is much\nless frequent that calling a chain.\n\nHere is the list of chains that we adjusted and their classifications.  None\nof them use the raw API, so for the moment it is only a placeholder.\n\n  ATOMIC CHAINS\n  -------------\narch/i386/kernel/traps.c:\t\ti386die_chain\narch/ia64/kernel/traps.c:\t\tia64die_chain\narch/powerpc/kernel/traps.c:\t\tpowerpc_die_chain\narch/sparc64/kernel/traps.c:\t\tsparc64die_chain\narch/x86_64/kernel/traps.c:\t\tdie_chain\ndrivers/char/ipmi/ipmi_si_intf.c:\txaction_notifier_list\nkernel/panic.c:\t\t\t\tpanic_notifier_list\nkernel/profile.c:\t\t\ttask_free_notifier\nnet/bluetooth/hci_core.c:\t\thci_notifier\nnet/ipv4/netfilter/ip_conntrack_core.c:\tip_conntrack_chain\nnet/ipv4/netfilter/ip_conntrack_core.c:\tip_conntrack_expect_chain\nnet/ipv6/addrconf.c:\t\t\tinet6addr_chain\nnet/netfilter/nf_conntrack_core.c:\tnf_conntrack_chain\nnet/netfilter/nf_conntrack_core.c:\tnf_conntrack_expect_chain\nnet/netlink/af_netlink.c:\t\tnetlink_chain\n\n  BLOCKING CHAINS\n  ---------------\narch/powerpc/platforms/pseries/reconfig.c:\tpSeries_reconfig_chain\narch/s390/kernel/process.c:\t\tidle_chain\narch/x86_64/kernel/process.c\t\tidle_notifier\ndrivers/base/memory.c:\t\t\tmemory_chain\ndrivers/cpufreq/cpufreq.c\t\tcpufreq_policy_notifier_list\ndrivers/cpufreq/cpufreq.c\t\tcpufreq_transition_notifier_list\ndrivers/macintosh/adb.c:\t\tadb_client_list\ndrivers/macintosh/via-pmu.c\t\tsleep_notifier_list\ndrivers/macintosh/via-pmu68k.c\t\tsleep_notifier_list\ndrivers/macintosh/windfarm_core.c\twf_client_list\ndrivers/usb/core/notify.c\t\tusb_notifier_list\ndrivers/video/fbmem.c\t\t\tfb_notifier_list\nkernel/cpu.c\t\t\t\tcpu_chain\nkernel/module.c\t\t\t\tmodule_notify_list\nkernel/profile.c\t\t\tmunmap_notifier\nkernel/profile.c\t\t\ttask_exit_notifier\nkernel/sys.c\t\t\t\treboot_notifier_list\nnet/core/dev.c\t\t\t\tnetdev_chain\nnet/decnet/dn_dev.c:\t\t\tdnaddr_chain\nnet/ipv4/devinet.c:\t\t\tinetaddr_chain\n\nIt\u0027s possible that some of these classifications are wrong.  If they are,\nplease let us know or submit a patch to fix them.  Note that any chain that\ngets called very frequently should be atomic, because the rwsem read-locking\nused for blocking chains is very likely to incur cache misses on SMP systems.\n(However, if the chain\u0027s callout routines may sleep then the chain cannot be\natomic.)\n\nThe patch set was written by Alan Stern and Chandra Seetharaman, incorporating\nmaterial written by Keith Owens and suggestions from Paul McKenney and Andrew\nMorton.\n\n[jes@sgi.com: restructure the notifier chain initialization macros]\nSigned-off-by: Alan Stern \u003cstern@rowland.harvard.edu\u003e\nSigned-off-by: Chandra Seetharaman \u003csekharan@us.ibm.com\u003e\nSigned-off-by: Jes Sorensen \u003cjes@sgi.com\u003e\nSigned-off-by: Andrew Morton \u003cakpm@osdl.org\u003e\nSigned-off-by: Linus Torvalds \u003ctorvalds@osdl.org\u003e\n"
    },
    {
      "commit": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
      "tree": "0bba044c4ce775e45a88a51686b5d9f90697ea9d",
      "parents": [],
      "author": {
        "name": "Linus Torvalds",
        "email": "torvalds@ppc970.osdl.org",
        "time": "Sat Apr 16 15:20:36 2005 -0700"
      },
      "committer": {
        "name": "Linus Torvalds",
        "email": "torvalds@ppc970.osdl.org",
        "time": "Sat Apr 16 15:20:36 2005 -0700"
      },
      "message": "Linux-2.6.12-rc2\n\nInitial git repository build. I\u0027m not bothering with the full history,\neven though we have it. We can create a separate \"historical\" git\narchive of that later if we want to, and in the meantime it\u0027s about\n3.2GB when imported into git - space that would just make the early\ngit days unnecessarily complicated, when we don\u0027t have a lot of good\ninfrastructure for it.\n\nLet it rip!\n"
    }
  ]
}
