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I did remove that code: |
Duplicate of: |
Patch has been merged and is in latest rpi-update firmware. |
popcornmix
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Feb 13, 2017
Dmitry reported a kernel warning: WARNING: CPU: 3 PID: 2936 at net/kcm/kcmsock.c:627 kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627 CPU: 3 PID: 2936 Comm: a.out Not tainted 4.10.0-rc6+ #209 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:15 [inline] dump_stack+0x2ee/0x3ef lib/dump_stack.c:51 panic+0x1fb/0x412 kernel/panic.c:179 __warn+0x1c4/0x1e0 kernel/panic.c:539 warn_slowpath_null+0x2c/0x40 kernel/panic.c:582 kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627 kcm_sendmsg+0x163a/0x2200 net/kcm/kcmsock.c:1029 sock_sendmsg_nosec net/socket.c:635 [inline] sock_sendmsg+0xca/0x110 net/socket.c:645 sock_write_iter+0x326/0x600 net/socket.c:848 new_sync_write fs/read_write.c:499 [inline] __vfs_write+0x483/0x740 fs/read_write.c:512 vfs_write+0x187/0x530 fs/read_write.c:560 SYSC_write fs/read_write.c:607 [inline] SyS_write+0xfb/0x230 fs/read_write.c:599 entry_SYSCALL_64_fastpath+0x1f/0xc2 when calling syscall(__NR_write, sock2, 0x208aaf27ul, 0x0ul) on a KCM seqpacket socket. It appears that kcm_sendmsg() does not handle len==0 case correctly, which causes an empty skb is allocated and queued. Fix this by skipping the skb allocation for len==0 case. Reported-by: Dmitry Vyukov <[email protected]> Cc: Tom Herbert <[email protected]> Signed-off-by: Cong Wang <[email protected]> Signed-off-by: David S. Miller <[email protected]>
popcornmix
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Feb 26, 2017
[ Upstream commit 98e3862 ] Dmitry reported a kernel warning: WARNING: CPU: 3 PID: 2936 at net/kcm/kcmsock.c:627 kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627 CPU: 3 PID: 2936 Comm: a.out Not tainted 4.10.0-rc6+ #209 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:15 [inline] dump_stack+0x2ee/0x3ef lib/dump_stack.c:51 panic+0x1fb/0x412 kernel/panic.c:179 __warn+0x1c4/0x1e0 kernel/panic.c:539 warn_slowpath_null+0x2c/0x40 kernel/panic.c:582 kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627 kcm_sendmsg+0x163a/0x2200 net/kcm/kcmsock.c:1029 sock_sendmsg_nosec net/socket.c:635 [inline] sock_sendmsg+0xca/0x110 net/socket.c:645 sock_write_iter+0x326/0x600 net/socket.c:848 new_sync_write fs/read_write.c:499 [inline] __vfs_write+0x483/0x740 fs/read_write.c:512 vfs_write+0x187/0x530 fs/read_write.c:560 SYSC_write fs/read_write.c:607 [inline] SyS_write+0xfb/0x230 fs/read_write.c:599 entry_SYSCALL_64_fastpath+0x1f/0xc2 when calling syscall(__NR_write, sock2, 0x208aaf27ul, 0x0ul) on a KCM seqpacket socket. It appears that kcm_sendmsg() does not handle len==0 case correctly, which causes an empty skb is allocated and queued. Fix this by skipping the skb allocation for len==0 case. Reported-by: Dmitry Vyukov <[email protected]> Cc: Tom Herbert <[email protected]> Signed-off-by: Cong Wang <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
popcornmix
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Jan 14, 2020
[ Upstream commit 92a3567 ] hsr nodes are protected by RCU and there is no write side lock. But node insertions and deletions could be being operated concurrently. So write side locking is needed. Test commands: ip netns add nst ip link add veth0 type veth peer name veth1 ip link add veth2 type veth peer name veth3 ip link set veth1 netns nst ip link set veth3 netns nst ip link set veth0 up ip link set veth2 up ip link add hsr0 type hsr slave1 veth0 slave2 veth2 ip a a 192.168.100.1/24 dev hsr0 ip link set hsr0 up ip netns exec nst ip link set veth1 up ip netns exec nst ip link set veth3 up ip netns exec nst ip link add hsr1 type hsr slave1 veth1 slave2 veth3 ip netns exec nst ip a a 192.168.100.2/24 dev hsr1 ip netns exec nst ip link set hsr1 up for i in {0..9} do for j in {0..9} do for k in {0..9} do for l in {0..9} do arping 192.168.100.2 -I hsr0 -s 00:01:3$i:4$j:5$k:6$l -c1 & done done done done Splat looks like: [ 236.066091][ T3286] list_add corruption. next->prev should be prev (ffff8880a5940300), but was ffff8880a5940d0. [ 236.069617][ T3286] ------------[ cut here ]------------ [ 236.070545][ T3286] kernel BUG at lib/list_debug.c:25! [ 236.071391][ T3286] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI [ 236.072343][ T3286] CPU: 0 PID: 3286 Comm: arping Tainted: G W 5.5.0-rc1+ #209 [ 236.073463][ T3286] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 236.074695][ T3286] RIP: 0010:__list_add_valid+0x74/0xd0 [ 236.075499][ T3286] Code: 48 39 da 75 27 48 39 f5 74 36 48 39 dd 74 31 48 83 c4 08 b8 01 00 00 00 5b 5d c3 48 b [ 236.078277][ T3286] RSP: 0018:ffff8880aaa97648 EFLAGS: 00010286 [ 236.086991][ T3286] RAX: 0000000000000075 RBX: ffff8880d4624c20 RCX: 0000000000000000 [ 236.088000][ T3286] RDX: 0000000000000075 RSI: 0000000000000008 RDI: ffffed1015552ebf [ 236.098897][ T3286] RBP: ffff88809b53d200 R08: ffffed101b3c04f9 R09: ffffed101b3c04f9 [ 236.099960][ T3286] R10: 00000000308769a1 R11: ffffed101b3c04f8 R12: ffff8880d4624c28 [ 236.100974][ T3286] R13: ffff8880d4624c20 R14: 0000000040310100 R15: ffff8880ce17ee02 [ 236.138967][ T3286] FS: 00007f23479fa680(0000) GS:ffff8880d9c00000(0000) knlGS:0000000000000000 [ 236.144852][ T3286] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 236.145720][ T3286] CR2: 00007f4a14bab210 CR3: 00000000a61c6001 CR4: 00000000000606f0 [ 236.146776][ T3286] Call Trace: [ 236.147222][ T3286] hsr_add_node+0x314/0x490 [hsr] [ 236.153633][ T3286] hsr_forward_skb+0x2b6/0x1bc0 [hsr] [ 236.154362][ T3286] ? rcu_read_lock_sched_held+0x90/0xc0 [ 236.155091][ T3286] ? rcu_read_lock_bh_held+0xa0/0xa0 [ 236.156607][ T3286] hsr_dev_xmit+0x70/0xd0 [hsr] [ 236.157254][ T3286] dev_hard_start_xmit+0x160/0x740 [ 236.157941][ T3286] __dev_queue_xmit+0x1961/0x2e10 [ 236.158565][ T3286] ? netdev_core_pick_tx+0x2e0/0x2e0 [ ... ] Reported-by: [email protected] Fixes: f421436 ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)") Signed-off-by: Taehee Yoo <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
sigmaris
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Feb 9, 2020
hsr nodes are protected by RCU and there is no write side lock. But node insertions and deletions could be being operated concurrently. So write side locking is needed. Test commands: ip netns add nst ip link add veth0 type veth peer name veth1 ip link add veth2 type veth peer name veth3 ip link set veth1 netns nst ip link set veth3 netns nst ip link set veth0 up ip link set veth2 up ip link add hsr0 type hsr slave1 veth0 slave2 veth2 ip a a 192.168.100.1/24 dev hsr0 ip link set hsr0 up ip netns exec nst ip link set veth1 up ip netns exec nst ip link set veth3 up ip netns exec nst ip link add hsr1 type hsr slave1 veth1 slave2 veth3 ip netns exec nst ip a a 192.168.100.2/24 dev hsr1 ip netns exec nst ip link set hsr1 up for i in {0..9} do for j in {0..9} do for k in {0..9} do for l in {0..9} do arping 192.168.100.2 -I hsr0 -s 00:01:3$i:4$j:5$k:6$l -c1 & done done done done Splat looks like: [ 236.066091][ T3286] list_add corruption. next->prev should be prev (ffff8880a5940300), but was ffff8880a5940d0. [ 236.069617][ T3286] ------------[ cut here ]------------ [ 236.070545][ T3286] kernel BUG at lib/list_debug.c:25! [ 236.071391][ T3286] invalid opcode: 0000 [raspberrypi#1] SMP DEBUG_PAGEALLOC KASAN PTI [ 236.072343][ T3286] CPU: 0 PID: 3286 Comm: arping Tainted: G W 5.5.0-rc1+ raspberrypi#209 [ 236.073463][ T3286] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 236.074695][ T3286] RIP: 0010:__list_add_valid+0x74/0xd0 [ 236.075499][ T3286] Code: 48 39 da 75 27 48 39 f5 74 36 48 39 dd 74 31 48 83 c4 08 b8 01 00 00 00 5b 5d c3 48 b [ 236.078277][ T3286] RSP: 0018:ffff8880aaa97648 EFLAGS: 00010286 [ 236.086991][ T3286] RAX: 0000000000000075 RBX: ffff8880d4624c20 RCX: 0000000000000000 [ 236.088000][ T3286] RDX: 0000000000000075 RSI: 0000000000000008 RDI: ffffed1015552ebf [ 236.098897][ T3286] RBP: ffff88809b53d200 R08: ffffed101b3c04f9 R09: ffffed101b3c04f9 [ 236.099960][ T3286] R10: 00000000308769a1 R11: ffffed101b3c04f8 R12: ffff8880d4624c28 [ 236.100974][ T3286] R13: ffff8880d4624c20 R14: 0000000040310100 R15: ffff8880ce17ee02 [ 236.138967][ T3286] FS: 00007f23479fa680(0000) GS:ffff8880d9c00000(0000) knlGS:0000000000000000 [ 236.144852][ T3286] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 236.145720][ T3286] CR2: 00007f4a14bab210 CR3: 00000000a61c6001 CR4: 00000000000606f0 [ 236.146776][ T3286] Call Trace: [ 236.147222][ T3286] hsr_add_node+0x314/0x490 [hsr] [ 236.153633][ T3286] hsr_forward_skb+0x2b6/0x1bc0 [hsr] [ 236.154362][ T3286] ? rcu_read_lock_sched_held+0x90/0xc0 [ 236.155091][ T3286] ? rcu_read_lock_bh_held+0xa0/0xa0 [ 236.156607][ T3286] hsr_dev_xmit+0x70/0xd0 [hsr] [ 236.157254][ T3286] dev_hard_start_xmit+0x160/0x740 [ 236.157941][ T3286] __dev_queue_xmit+0x1961/0x2e10 [ 236.158565][ T3286] ? netdev_core_pick_tx+0x2e0/0x2e0 [ ... ] Reported-by: [email protected] Fixes: f421436 ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)") Signed-off-by: Taehee Yoo <[email protected]> Signed-off-by: David S. Miller <[email protected]>
popcornmix
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Nov 21, 2023
…vice [ Upstream commit 7d0bc63 ] Commit 19b8766 ("firmware: arm_ffa: Fix FFA device names for logical partitions") added an ID to the FFA device using ida_alloc() and append the same to "arm-ffa" to make up a unique device name. However it missed to stash the id value in ffa_dev to help freeing the ID later when the device is destroyed. Due to the missing/unassigned ID in FFA device, we get the following warning when the FF-A device is unregistered. | ida_free called for id=0 which is not allocated. | WARNING: CPU: 7 PID: 1 at lib/idr.c:525 ida_free+0x114/0x164 | CPU: 7 PID: 1 Comm: swapper/0 Not tainted 6.6.0-rc4 #209 | pstate: 61400009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) | pc : ida_free+0x114/0x164 | lr : ida_free+0x114/0x164 | Call trace: | ida_free+0x114/0x164 | ffa_release_device+0x24/0x3c | device_release+0x34/0x8c | kobject_put+0x94/0xf8 | put_device+0x18/0x24 | klist_devices_put+0x14/0x20 | klist_next+0xc8/0x114 | bus_for_each_dev+0xd8/0x144 | arm_ffa_bus_exit+0x30/0x54 | ffa_init+0x68/0x330 | do_one_initcall+0xdc/0x250 | do_initcall_level+0x8c/0xac | do_initcalls+0x54/0x94 | do_basic_setup+0x1c/0x28 | kernel_init_freeable+0x104/0x170 | kernel_init+0x20/0x1a0 | ret_from_fork+0x10/0x20 Fix the same by actually assigning the ID in the FFA device this time for real. Fixes: 19b8766 ("firmware: arm_ffa: Fix FFA device names for logical partitions") Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sudeep Holla <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
popcornmix
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Nov 21, 2023
…vice [ Upstream commit 7d0bc63 ] Commit 19b8766 ("firmware: arm_ffa: Fix FFA device names for logical partitions") added an ID to the FFA device using ida_alloc() and append the same to "arm-ffa" to make up a unique device name. However it missed to stash the id value in ffa_dev to help freeing the ID later when the device is destroyed. Due to the missing/unassigned ID in FFA device, we get the following warning when the FF-A device is unregistered. | ida_free called for id=0 which is not allocated. | WARNING: CPU: 7 PID: 1 at lib/idr.c:525 ida_free+0x114/0x164 | CPU: 7 PID: 1 Comm: swapper/0 Not tainted 6.6.0-rc4 #209 | pstate: 61400009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) | pc : ida_free+0x114/0x164 | lr : ida_free+0x114/0x164 | Call trace: | ida_free+0x114/0x164 | ffa_release_device+0x24/0x3c | device_release+0x34/0x8c | kobject_put+0x94/0xf8 | put_device+0x18/0x24 | klist_devices_put+0x14/0x20 | klist_next+0xc8/0x114 | bus_for_each_dev+0xd8/0x144 | arm_ffa_bus_exit+0x30/0x54 | ffa_init+0x68/0x330 | do_one_initcall+0xdc/0x250 | do_initcall_level+0x8c/0xac | do_initcalls+0x54/0x94 | do_basic_setup+0x1c/0x28 | kernel_init_freeable+0x104/0x170 | kernel_init+0x20/0x1a0 | ret_from_fork+0x10/0x20 Fix the same by actually assigning the ID in the FFA device this time for real. Fixes: 19b8766 ("firmware: arm_ffa: Fix FFA device names for logical partitions") Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sudeep Holla <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
popcornmix
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Nov 21, 2023
…vice [ Upstream commit 7d0bc63 ] Commit 19b8766 ("firmware: arm_ffa: Fix FFA device names for logical partitions") added an ID to the FFA device using ida_alloc() and append the same to "arm-ffa" to make up a unique device name. However it missed to stash the id value in ffa_dev to help freeing the ID later when the device is destroyed. Due to the missing/unassigned ID in FFA device, we get the following warning when the FF-A device is unregistered. | ida_free called for id=0 which is not allocated. | WARNING: CPU: 7 PID: 1 at lib/idr.c:525 ida_free+0x114/0x164 | CPU: 7 PID: 1 Comm: swapper/0 Not tainted 6.6.0-rc4 #209 | pstate: 61400009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) | pc : ida_free+0x114/0x164 | lr : ida_free+0x114/0x164 | Call trace: | ida_free+0x114/0x164 | ffa_release_device+0x24/0x3c | device_release+0x34/0x8c | kobject_put+0x94/0xf8 | put_device+0x18/0x24 | klist_devices_put+0x14/0x20 | klist_next+0xc8/0x114 | bus_for_each_dev+0xd8/0x144 | arm_ffa_bus_exit+0x30/0x54 | ffa_init+0x68/0x330 | do_one_initcall+0xdc/0x250 | do_initcall_level+0x8c/0xac | do_initcalls+0x54/0x94 | do_basic_setup+0x1c/0x28 | kernel_init_freeable+0x104/0x170 | kernel_init+0x20/0x1a0 | ret_from_fork+0x10/0x20 Fix the same by actually assigning the ID in the FFA device this time for real. Fixes: 19b8766 ("firmware: arm_ffa: Fix FFA device names for logical partitions") Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sudeep Holla <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
popcornmix
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Jun 24, 2024
The large folio is mapped with folio size(not greater PMD_SIZE) aligned virtual address during the pagefault, ie, 'addr = ALIGN_DOWN(vmf->address, nr_pages * PAGE_SIZE)' in do_anonymous_page(). But after the mremap(), the virtual address only requires PAGE_SIZE alignment. Also pte is moved to new in move_page_tables(), then traversal of the new pte in the numa_rebuild_large_mapping() could hit the following issue, Unable to handle kernel paging request at virtual address 00000a80c021a788 Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=00002040341a6000 [00000a80c021a788] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 0000000096000004 [#1] SMP ... CPU: 76 PID: 15187 Comm: git Kdump: loaded Tainted: G W 6.10.0-rc2+ #209 Hardware name: Huawei TaiShan 2280 V2/BC82AMDD, BIOS 1.79 08/21/2021 pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : numa_rebuild_large_mapping+0x338/0x638 lr : numa_rebuild_large_mapping+0x320/0x638 sp : ffff8000b41c3b00 x29: ffff8000b41c3b30 x28: ffff8000812a0000 x27: 00000000000a8000 x26: 00000000000000a8 x25: 0010000000000001 x24: ffff20401c7170f0 x23: 0000ffff33a1e000 x22: 0000ffff33a76000 x21: ffff20400869eca0 x20: 0000ffff33976000 x19: 00000000000000a8 x18: ffffffffffffffff x17: 0000000000000000 x16: 0000000000000020 x15: ffff8000b41c36a8 x14: 0000000000000000 x13: 205d373831353154 x12: 5b5d333331363732 x11: 000000000011ff78 x10: 000000000011ff10 x9 : ffff800080273f30 x8 : 000000320400869e x7 : c0000000ffffd87f x6 : 00000000001e6ba8 x5 : ffff206f3fb5af88 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000000 x1 : fffffdffc0000000 x0 : 00000a80c021a780 Call trace: numa_rebuild_large_mapping+0x338/0x638 do_numa_page+0x3e4/0x4e0 handle_pte_fault+0x1bc/0x238 __handle_mm_fault+0x20c/0x400 handle_mm_fault+0xa8/0x288 do_page_fault+0x124/0x498 do_translation_fault+0x54/0x80 do_mem_abort+0x4c/0xa8 el0_da+0x40/0x110 el0t_64_sync_handler+0xe4/0x158 el0t_64_sync+0x188/0x190 Fix it by making the start and end not only within the vma range, but also within the page table range. Link: https://lkml.kernel.org/r/[email protected] Fixes: d2136d7 ("mm: support multi-size THP numa balancing") Signed-off-by: Kefeng Wang <[email protected]> Acked-by: David Hildenbrand <[email protected]> Reviewed-by: Baolin Wang <[email protected]> Cc: "Huang, Ying" <[email protected]> Cc: John Hubbard <[email protected]> Cc: Liu Shixin <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Ryan Roberts <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
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I'm trying to set up a serial communication between the RPI and an
FPGA. However, there is an issue when using the standard C library
open() to init the serial interface: I'm using a scope to monitor what
is sent and received via the RX and TX lines. A call to open causes
the TX line of the RPI to go low for the length of one bit. I do not
see this behavior with other computers/linux PCs. The point is, the
FPGA assumes a valid transmission, since he thinks it's a start bit,
but it's not.
I checked with minicom installed on the RPI. Same thing. Starting
minicom causes the TX line sending one bit. Once minicom has started,
the communication runs as expected and all bytes have the correct
frame size. Is there any way to suppress the TX line going low upon
the open call to init the serial communication? A smart guy at
stackoverflow suggested:
http://stackoverflow.com/questions/14579974/init-a-serial-
communication-with-c-library-open-causes-tx-to-send-one-bit-on-r
Thanks
N.
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