bisecting fixing commit since ad347abe4a9876b1f65f408ab467137e88f77eb4
building syzkaller on 1ba81399e2d03b53a7e631c4ab05f25af1fb1911
testing commit ad347abe4a9876b1f65f408ab467137e88f77eb4
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: 865d3c40c172cafc1eeff01355f98b9738f56605a5dc669616daa8f5df3b4827
run #0: crashed: BUG: sleeping function called from invalid context in lock_sock_nested
run #1: crashed: KASAN: out-of-bounds Read in __show_regs
run #2: OK
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
run #10: OK
run #11: OK
run #12: OK
run #13: OK
run #14: OK
run #15: OK
run #16: OK
run #17: OK
run #18: OK
run #19: OK
reproducer seems to be flaky
testing current HEAD 64222515138e43da1fcf288f0289ef1020427b87
testing commit 64222515138e43da1fcf288f0289ef1020427b87
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: ee9bc46a9e5c63d5a6c7e3570810587b24b3c472df258efd968fb5730051ab13
all runs: OK
# git bisect start 64222515138e43da1fcf288f0289ef1020427b87 ad347abe4a9876b1f65f408ab467137e88f77eb4
Bisecting: 14784 revisions left to test after this (roughly 14 steps)
[450405cdc0e18b899925b87aa4d1e84775082450] Merge tag 'gvt-fixes-2021-07-15' of https://github.com/intel/gvt-linux into drm-intel-fixes

testing commit 450405cdc0e18b899925b87aa4d1e84775082450
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: 8796d6568993862b982cc00999a2f4095010c73d001ab3307302147b0a611f1e
run #0: crashed: KASAN: stack-out-of-bounds Read in __show_regs
run #1: crashed: INFO: task hung in linkwatch_event
run #2: OK
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
run #10: OK
run #11: OK
run #12: OK
run #13: OK
run #14: OK
run #15: OK
run #16: OK
run #17: OK
run #18: OK
run #19: OK
# git bisect good 450405cdc0e18b899925b87aa4d1e84775082450
Bisecting: 7722 revisions left to test after this (roughly 13 steps)
[1b4f3dfb4792f03b139edf10124fcbeb44e608e6] Merge tag 'usb-serial-5.15-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next

testing commit 1b4f3dfb4792f03b139edf10124fcbeb44e608e6
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: 6d4e78528c702e2d938d8cb4ec69a943c49c4f9f0b2a309be340b495900cbc85
run #0: crashed: KFENCE: use-after-free in kvm_fastop_exception
run #1: crashed: KASAN: use-after-free Read in __d_alloc
run #2: crashed: KFENCE: use-after-free in kvm_fastop_exception
run #3: crashed: KASAN: use-after-free Read in __d_alloc
run #4: crashed: KASAN: use-after-free Read in __d_alloc
run #5: crashed: KASAN: use-after-free Read in __d_alloc
run #6: crashed: KFENCE: use-after-free in kvm_fastop_exception
run #7: OK
run #8: OK
run #9: OK
run #10: OK
run #11: OK
run #12: OK
run #13: OK
run #14: OK
run #15: OK
run #16: OK
run #17: OK
run #18: OK
run #19: OK
# git bisect good 1b4f3dfb4792f03b139edf10124fcbeb44e608e6
Bisecting: 3862 revisions left to test after this (roughly 12 steps)
[f1583cb1be35c23df60b1c39e3e7e6704d749d0b] Merge tag 'linux-kselftest-next-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

testing commit f1583cb1be35c23df60b1c39e3e7e6704d749d0b
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: 06558a1912a30a73ce4a4791a1edd11650dacfb4bc28346477e715dfeb36a401
run #0: crashed: KFENCE: use-after-free in kvm_fastop_exception
run #1: OK
run #2: crashed: KASAN: use-after-free Read in __d_alloc
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
run #10: OK
run #11: OK
run #12: OK
run #13: OK
run #14: OK
run #15: OK
run #16: crashed: KASAN: use-after-free Read in __d_alloc
run #17: OK
run #18: boot failed: possible deadlock in blktrans_open
run #19: boot failed: possible deadlock in blktrans_open
# git bisect good f1583cb1be35c23df60b1c39e3e7e6704d749d0b
Bisecting: 1930 revisions left to test after this (roughly 11 steps)
[e700ac213a0f793fb4f83098413303e3dd080892] Merge branch 'pruss-fix' into fixes

testing commit e700ac213a0f793fb4f83098413303e3dd080892
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: ce277ad2be0f82b5108c1da6522fba72bdc74763c4e02b5f9312026ba37c8cfb
run #0: crashed: KASAN: out-of-bounds Read in __show_regs
run #1: OK
run #2: OK
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
run #10: OK
run #11: OK
run #12: OK
run #13: OK
run #14: OK
run #15: OK
run #16: OK
run #17: OK
run #18: OK
run #19: boot failed: can't ssh into the instance
# git bisect good e700ac213a0f793fb4f83098413303e3dd080892
Bisecting: 962 revisions left to test after this (roughly 10 steps)
[84928ce3bb4e20ec7ef0e990630a690855dd44cc] Merge tag 'driver-core-5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

testing commit 84928ce3bb4e20ec7ef0e990630a690855dd44cc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: d1a7a0d9bf26a72d1f6a4a7b96f3aeeda00c679ea1464138e4c67b00ade05347
run #0: crashed: KASAN: out-of-bounds Read in __show_regs
run #1: crashed: WARNING in __cfg80211_ibss_joined
run #2: OK
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
run #10: OK
run #11: OK
run #12: OK
run #13: OK
run #14: OK
run #15: OK
run #16: OK
run #17: OK
run #18: OK
run #19: OK
# git bisect good 84928ce3bb4e20ec7ef0e990630a690855dd44cc
Bisecting: 470 revisions left to test after this (roughly 9 steps)
[ec681c53f8d2d0ee362ff67f5b98dd8263c15002] Merge tag 'net-5.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

testing commit ec681c53f8d2d0ee362ff67f5b98dd8263c15002
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: f529a6cfa94d7113167c56c5558518c3b08a78928a70f8efb0ad9c3aeb59cf3c
all runs: OK
# git bisect bad ec681c53f8d2d0ee362ff67f5b98dd8263c15002
Bisecting: 245 revisions left to test after this (roughly 8 steps)
[9973a43012b6ad1720dbc4d5faf5302c28635b8c] r8152: select CRC32 and CRYPTO/CRYPTO_HASH/CRYPTO_SHA256

testing commit 9973a43012b6ad1720dbc4d5faf5302c28635b8c
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: e840cf5367d7401bbdf034b8cdcef887eca59121fc0e2d35d74f78ef3fc3931f
run #0: crashed: KASAN: stack-out-of-bounds Read in __show_regs
run #1: crashed: KASAN: out-of-bounds Read in __show_regs
run #2: crashed: KASAN: stack-out-of-bounds Read in __show_regs
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
run #10: OK
run #11: OK
run #12: OK
run #13: OK
run #14: OK
run #15: OK
run #16: OK
run #17: OK
run #18: OK
run #19: OK
# git bisect good 9973a43012b6ad1720dbc4d5faf5302c28635b8c
Bisecting: 124 revisions left to test after this (roughly 7 steps)
[c22ccc4a3ef198752855f44e9279732260c889d5] Merge tag 'x86_urgent_for_v5.15_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

testing commit c22ccc4a3ef198752855f44e9279732260c889d5
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: 13c02fcb0e7f1bb7faea8de566ee1f7b910aba82c036b1c1fbd95c287a297963
run #0: crashed: KASAN: out-of-bounds Read in __show_regs
run #1: OK
run #2: OK
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
run #10: OK
run #11: OK
run #12: OK
run #13: OK
run #14: OK
run #15: OK
run #16: OK
run #17: OK
run #18: OK
run #19: OK
# git bisect good c22ccc4a3ef198752855f44e9279732260c889d5
Bisecting: 63 revisions left to test after this (roughly 6 steps)
[ed47291911d375f7d0bf63b9afb7516988305d94] Merge tag 'platform-drivers-x86-v5.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86

testing commit ed47291911d375f7d0bf63b9afb7516988305d94
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: ad324476b14e2d7c7f64cfe9d763755c181428a96dc8fa57b3229de82a86d9a7
run #0: crashed: KASAN: stack-out-of-bounds Read in __show_regs
run #1: OK
run #2: OK
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
run #10: OK
run #11: OK
run #12: OK
run #13: OK
run #14: OK
run #15: OK
run #16: OK
run #17: OK
run #18: OK
run #19: OK
# git bisect good ed47291911d375f7d0bf63b9afb7516988305d94
Bisecting: 31 revisions left to test after this (roughly 5 steps)
[1f922d9e374f0ca7d1b241666c792f403c6120aa] Revert "net: procfs: add seq_puts() statement for dev_mcast"

testing commit 1f922d9e374f0ca7d1b241666c792f403c6120aa
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: 9a8beb61aacc1ae1b679efad7fd34b4b92c0c35c2932f7f4d7b718fe1b308829
all runs: OK
# git bisect bad 1f922d9e374f0ca7d1b241666c792f403c6120aa
Bisecting: 15 revisions left to test after this (roughly 4 steps)
[deab6b1cd9789bb9bd466d5e76aecb8b336259b4] net: dsa: tag_ocelot: break circular dependency with ocelot switch lib driver

testing commit deab6b1cd9789bb9bd466d5e76aecb8b336259b4
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: cbf390c9ca894469ceb6e8e95491f8f6c8f6a626eb3b75bc70f9cba501926fa2
run #0: crashed: KASAN: out-of-bounds Read in __show_regs
run #1: OK
run #2: OK
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
run #10: OK
run #11: OK
run #12: OK
run #13: OK
run #14: OK
run #15: OK
run #16: OK
run #17: OK
run #18: OK
run #19: OK
# git bisect good deab6b1cd9789bb9bd466d5e76aecb8b336259b4
Bisecting: 8 revisions left to test after this (roughly 3 steps)
[427f974d9727ca681085ddcd0530c97ab5811ae0] net: korina: select CRC32

testing commit 427f974d9727ca681085ddcd0530c97ab5811ae0
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: 1768a13d1c5ca588658a77a3cd3a2416db781327bec89c5862149aea81f7ecb7
all runs: OK
# git bisect bad 427f974d9727ca681085ddcd0530c97ab5811ae0
Bisecting: 3 revisions left to test after this (roughly 2 steps)
[43ba33b4f143965a451cfdc1e826b61f6933c887] net: dsa: tag_ocelot_8021q: fix inability to inject STP BPDUs into BLOCKING ports

testing commit 43ba33b4f143965a451cfdc1e826b61f6933c887
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: 1768a13d1c5ca588658a77a3cd3a2416db781327bec89c5862149aea81f7ecb7
all runs: OK
# git bisect bad 43ba33b4f143965a451cfdc1e826b61f6933c887
Bisecting: 0 revisions left to test after this (roughly 1 step)
[1328a883258b4507909090ed0a9ad63771f9f780] net: dsa: felix: purge skb from TX timestamping queue if it cannot be sent

testing commit 1328a883258b4507909090ed0a9ad63771f9f780
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: 1768a13d1c5ca588658a77a3cd3a2416db781327bec89c5862149aea81f7ecb7
all runs: OK
# git bisect bad 1328a883258b4507909090ed0a9ad63771f9f780
Bisecting: 0 revisions left to test after this (roughly 0 steps)
[49f885b2d97093451410e7279aa29d81e094e108] net: dsa: tag_ocelot_8021q: break circular dependency with ocelot switch lib

testing commit 49f885b2d97093451410e7279aa29d81e094e108
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: 1768a13d1c5ca588658a77a3cd3a2416db781327bec89c5862149aea81f7ecb7
run #0: crashed: KASAN: out-of-bounds Read in __show_regs
run #1: crashed: KASAN: out-of-bounds Read in __show_regs
run #2: crashed: KASAN: stack-out-of-bounds Read in __show_regs
run #3: crashed: KASAN: stack-out-of-bounds Read in __show_regs
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
run #10: OK
run #11: OK
run #12: OK
run #13: OK
run #14: OK
run #15: OK
run #16: OK
run #17: OK
run #18: OK
run #19: OK
# git bisect good 49f885b2d97093451410e7279aa29d81e094e108
1328a883258b4507909090ed0a9ad63771f9f780 is the first bad commit
commit 1328a883258b4507909090ed0a9ad63771f9f780
Author: Vladimir Oltean <vladimir.oltean@nxp.com>
Date:   Tue Oct 12 14:40:42 2021 +0300

    net: dsa: felix: purge skb from TX timestamping queue if it cannot be sent
    
    At present, when a PTP packet which requires TX timestamping gets
    dropped under congestion by the switch, things go downhill very fast.
    The driver keeps a clone of that skb in a queue of packets awaiting TX
    timestamp interrupts, but interrupts will never be raised for the
    dropped packets.
    
    Moreover, matching timestamped packets to timestamps is done by a 2-bit
    timestamp ID, and this can wrap around and we can match on the wrong skb.
    
    Since with the default NPI-based tagging protocol, we get no notification
    about packet drops, the best we can do is eventually recover from the
    drop of a PTP frame: its skb will be dead memory until another skb which
    was assigned the same timestamp ID happens to find it.
    
    However, with the ocelot-8021q tagger which injects packets using the
    manual register interface, it appears that we can check for more
    information, such as:
    
    - whether the input queue has reached the high watermark or not
    - whether the injection group's FIFO can accept additional data or not
    
    so we know that a PTP frame is likely to get dropped before actually
    sending it, and drop it ourselves (because DSA uses NETIF_F_LLTX, so it
    can't return NETDEV_TX_BUSY to ask the qdisc to requeue the packet).
    
    But when we do that, we can also remove the skb from the timestamping
    queue, because there surely won't be any timestamp that matches it.
    
    Fixes: 0a6f17c6ae21 ("net: dsa: tag_ocelot_8021q: add support for PTP timestamping")
    Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
    Signed-off-by: Jakub Kicinski <kuba@kernel.org>

 drivers/net/dsa/ocelot/felix.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

culprit signature: 1768a13d1c5ca588658a77a3cd3a2416db781327bec89c5862149aea81f7ecb7
parent  signature: 1768a13d1c5ca588658a77a3cd3a2416db781327bec89c5862149aea81f7ecb7
Reproducer flagged being flaky
revisions tested: 17, total time: 4h36m10.747180134s (build: 1h53m13.33518336s, test: 2h41m1.78837243s)
first good commit: 1328a883258b4507909090ed0a9ad63771f9f780 net: dsa: felix: purge skb from TX timestamping queue if it cannot be sent
recipients (to): ["UNGLinuxDriver@microchip.com" "alexandre.belloni@bootlin.com" "andrew@lunn.ch" "claudiu.manoil@nxp.com" "davem@davemloft.net" "f.fainelli@gmail.com" "kuba@kernel.org" "kuba@kernel.org" "netdev@vger.kernel.org" "vivien.didelot@gmail.com" "vladimir.oltean@nxp.com" "vladimir.oltean@nxp.com"]
recipients (cc): ["linux-kernel@vger.kernel.org"]