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nati_x86_64_defconfig: Build Hyper-V support in#58

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gratian merged 1 commit intoni:nilrt/master/5.15from
chaitu236:nilrt/master/5.15
Mar 16, 2022
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nati_x86_64_defconfig: Build Hyper-V support in#58
gratian merged 1 commit intoni:nilrt/master/5.15from
chaitu236:nilrt/master/5.15

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@chaitu236 chaitu236 commented Mar 15, 2022

Build required Hyper-V modules into kernel as we no longer have
initramfs in runmode to load them.

Testing

Built kernel and modules locally, copied them over to rootfs partition in a HyperV target and verified runmode boots.

Note
Hyper-V keyboard module is still built as a module since it depends on SERIO which is configured as a module. Leaving it as is since it is not required for loading rootfs.

Build required Hyper-V modules into kernel as we no longer have
initramfs in runmode to load them.

Signed-off-by: Chaitanya Vadrevu <chaitanya.vadrevu@ni.com>
@chaitu236 chaitu236 requested review from a team, bstreiff and gratian March 15, 2022 22:54
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LGTM. For posterity this adds around 89 kB to the kernel bzImage which is an acceptable tradeoff.

@gratian gratian merged commit 2360492 into ni:nilrt/master/5.15 Mar 16, 2022
@chaitu236 chaitu236 deleted the nilrt/master/5.15 branch March 16, 2022 16:04
gratian pushed a commit that referenced this pull request May 10, 2022
[ Upstream commit 8d3ea3d ]

GCC12 appears to be much smarter about its dependency tracking and is
aware that the relaxed variants are just normal loads and stores and
this is causing problems like:

[  210.074549] ------------[ cut here ]------------
[  210.079223] NETDEV WATCHDOG: enabcm6e4ei0 (bcmgenet): transmit queue 1 timed out
[  210.086717] WARNING: CPU: 1 PID: 0 at net/sched/sch_generic.c:529 dev_watchdog+0x234/0x240
[  210.095044] Modules linked in: genet(E) nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat]
[  210.146561] ACPI CPPC: PCC check channel failed for ss: 0. ret=-110
[  210.146927] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G            E     5.17.0-rc7G12+ #58
[  210.153226] CPPC Cpufreq:cppc_scale_freq_workfn: failed to read perf counters
[  210.161349] Hardware name: Raspberry Pi Foundation Raspberry Pi 4 Model B/Raspberry Pi 4 Model B, BIOS EDK2-DEV 02/08/2022
[  210.161353] pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  210.161358] pc : dev_watchdog+0x234/0x240
[  210.161364] lr : dev_watchdog+0x234/0x240
[  210.161368] sp : ffff8000080a3a40
[  210.161370] x29: ffff8000080a3a40 x28: ffffcd425af87000 x27: ffff8000080a3b20
[  210.205150] x26: ffffcd425aa00000 x25: 0000000000000001 x24: ffffcd425af8ec08
[  210.212321] x23: 0000000000000100 x22: ffffcd425af87000 x21: ffff55b142688000
[  210.219491] x20: 0000000000000001 x19: ffff55b1426884c8 x18: ffffffffffffffff
[  210.226661] x17: 64656d6974203120 x16: 0000000000000001 x15: 6d736e617274203a
[  210.233831] x14: 2974656e65676d63 x13: ffffcd4259c300d8 x12: ffffcd425b07d5f0
[  210.241001] x11: 00000000ffffffff x10: ffffcd425b07d5f0 x9 : ffffcd4258bdad9c
[  210.248171] x8 : 00000000ffffdfff x7 : 000000000000003f x6 : 0000000000000000
[  210.255341] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000001000
[  210.262511] x2 : 0000000000001000 x1 : 0000000000000005 x0 : 0000000000000044
[  210.269682] Call trace:
[  210.272133]  dev_watchdog+0x234/0x240
[  210.275811]  call_timer_fn+0x3c/0x15c
[  210.279489]  __run_timers.part.0+0x288/0x310
[  210.283777]  run_timer_softirq+0x48/0x80
[  210.287716]  __do_softirq+0x128/0x360
[  210.291392]  __irq_exit_rcu+0x138/0x140
[  210.295243]  irq_exit_rcu+0x1c/0x30
[  210.298745]  el1_interrupt+0x38/0x54
[  210.302334]  el1h_64_irq_handler+0x18/0x24
[  210.306445]  el1h_64_irq+0x7c/0x80
[  210.309857]  arch_cpu_idle+0x18/0x2c
[  210.313445]  default_idle_call+0x4c/0x140
[  210.317470]  cpuidle_idle_call+0x14c/0x1a0
[  210.321584]  do_idle+0xb0/0x100
[  210.324737]  cpu_startup_entry+0x30/0x8c
[  210.328675]  secondary_start_kernel+0xe4/0x110
[  210.333138]  __secondary_switched+0x94/0x98

The assumption when these were relaxed seems to be that device memory
would be mapped non reordering, and that other constructs
(spinlocks/etc) would provide the barriers to assure that packet data
and in memory rings/queues were ordered with respect to device
register reads/writes. This itself seems a bit sketchy, but the real
problem with GCC12 is that it is moving the actual reads/writes around
at will as though they were independent operations when in truth they
are not, but the compiler can't know that. When looking at the
assembly dumps for many of these routines its possible to see very
clean, but not strictly in program order operations occurring as the
compiler would be free to do if these weren't actually register
reads/write operations.

Its possible to suppress the timeout with a liberal bit of dma_mb()'s
sprinkled around but the device still seems unable to reliably
send/receive data. A better plan is to use the safer readl/writel
everywhere.

Since this partially reverts an older commit, which notes the use of
the relaxed variants for performance reasons. I would suggest that
any performance problems with this commit are targeted at relaxing only
the performance critical code paths after assuring proper barriers.

Fixes: 69d2ea9 ("net: bcmgenet: Use correct I/O accessors")
Reported-by: Peter Robinson <pbrobinson@gmail.com>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Acked-by: Peter Robinson <pbrobinson@gmail.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20220310045358.224350-1-jeremy.linton@arm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
gratian pushed a commit to gratian/linux that referenced this pull request May 19, 2022
[ Upstream commit 8d3ea3d ]

GCC12 appears to be much smarter about its dependency tracking and is
aware that the relaxed variants are just normal loads and stores and
this is causing problems like:

[  210.074549] ------------[ cut here ]------------
[  210.079223] NETDEV WATCHDOG: enabcm6e4ei0 (bcmgenet): transmit queue 1 timed out
[  210.086717] WARNING: CPU: 1 PID: 0 at net/sched/sch_generic.c:529 dev_watchdog+0x234/0x240
[  210.095044] Modules linked in: genet(E) nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat]
[  210.146561] ACPI CPPC: PCC check channel failed for ss: 0. ret=-110
[  210.146927] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G            E     5.17.0-rc7G12+ ni#58
[  210.153226] CPPC Cpufreq:cppc_scale_freq_workfn: failed to read perf counters
[  210.161349] Hardware name: Raspberry Pi Foundation Raspberry Pi 4 Model B/Raspberry Pi 4 Model B, BIOS EDK2-DEV 02/08/2022
[  210.161353] pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  210.161358] pc : dev_watchdog+0x234/0x240
[  210.161364] lr : dev_watchdog+0x234/0x240
[  210.161368] sp : ffff8000080a3a40
[  210.161370] x29: ffff8000080a3a40 x28: ffffcd425af87000 x27: ffff8000080a3b20
[  210.205150] x26: ffffcd425aa00000 x25: 0000000000000001 x24: ffffcd425af8ec08
[  210.212321] x23: 0000000000000100 x22: ffffcd425af87000 x21: ffff55b142688000
[  210.219491] x20: 0000000000000001 x19: ffff55b1426884c8 x18: ffffffffffffffff
[  210.226661] x17: 64656d6974203120 x16: 0000000000000001 x15: 6d736e617274203a
[  210.233831] x14: 2974656e65676d63 x13: ffffcd4259c300d8 x12: ffffcd425b07d5f0
[  210.241001] x11: 00000000ffffffff x10: ffffcd425b07d5f0 x9 : ffffcd4258bdad9c
[  210.248171] x8 : 00000000ffffdfff x7 : 000000000000003f x6 : 0000000000000000
[  210.255341] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000001000
[  210.262511] x2 : 0000000000001000 x1 : 0000000000000005 x0 : 0000000000000044
[  210.269682] Call trace:
[  210.272133]  dev_watchdog+0x234/0x240
[  210.275811]  call_timer_fn+0x3c/0x15c
[  210.279489]  __run_timers.part.0+0x288/0x310
[  210.283777]  run_timer_softirq+0x48/0x80
[  210.287716]  __do_softirq+0x128/0x360
[  210.291392]  __irq_exit_rcu+0x138/0x140
[  210.295243]  irq_exit_rcu+0x1c/0x30
[  210.298745]  el1_interrupt+0x38/0x54
[  210.302334]  el1h_64_irq_handler+0x18/0x24
[  210.306445]  el1h_64_irq+0x7c/0x80
[  210.309857]  arch_cpu_idle+0x18/0x2c
[  210.313445]  default_idle_call+0x4c/0x140
[  210.317470]  cpuidle_idle_call+0x14c/0x1a0
[  210.321584]  do_idle+0xb0/0x100
[  210.324737]  cpu_startup_entry+0x30/0x8c
[  210.328675]  secondary_start_kernel+0xe4/0x110
[  210.333138]  __secondary_switched+0x94/0x98

The assumption when these were relaxed seems to be that device memory
would be mapped non reordering, and that other constructs
(spinlocks/etc) would provide the barriers to assure that packet data
and in memory rings/queues were ordered with respect to device
register reads/writes. This itself seems a bit sketchy, but the real
problem with GCC12 is that it is moving the actual reads/writes around
at will as though they were independent operations when in truth they
are not, but the compiler can't know that. When looking at the
assembly dumps for many of these routines its possible to see very
clean, but not strictly in program order operations occurring as the
compiler would be free to do if these weren't actually register
reads/write operations.

Its possible to suppress the timeout with a liberal bit of dma_mb()'s
sprinkled around but the device still seems unable to reliably
send/receive data. A better plan is to use the safer readl/writel
everywhere.

Since this partially reverts an older commit, which notes the use of
the relaxed variants for performance reasons. I would suggest that
any performance problems with this commit are targeted at relaxing only
the performance critical code paths after assuring proper barriers.

Fixes: 69d2ea9 ("net: bcmgenet: Use correct I/O accessors")
Reported-by: Peter Robinson <pbrobinson@gmail.com>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Acked-by: Peter Robinson <pbrobinson@gmail.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20220310045358.224350-1-jeremy.linton@arm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
gratian pushed a commit that referenced this pull request Apr 12, 2024
[ Upstream commit 32019c6 ]

When trying to use copy_from_kernel_nofault() to read vsyscall page
through a bpf program, the following oops was reported:

  BUG: unable to handle page fault for address: ffffffffff600000
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 3231067 P4D 3231067 PUD 3233067 PMD 3235067 PTE 0
  Oops: 0000 [#1] PREEMPT SMP PTI
  CPU: 1 PID: 20390 Comm: test_progs ...... 6.7.0+ #58
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......
  RIP: 0010:copy_from_kernel_nofault+0x6f/0x110
  ......
  Call Trace:
   <TASK>
   ? copy_from_kernel_nofault+0x6f/0x110
   bpf_probe_read_kernel+0x1d/0x50
   bpf_prog_2061065e56845f08_do_probe_read+0x51/0x8d
   trace_call_bpf+0xc5/0x1c0
   perf_call_bpf_enter.isra.0+0x69/0xb0
   perf_syscall_enter+0x13e/0x200
   syscall_trace_enter+0x188/0x1c0
   do_syscall_64+0xb5/0xe0
   entry_SYSCALL_64_after_hwframe+0x6e/0x76
   </TASK>
  ......
  ---[ end trace 0000000000000000 ]---

The oops is triggered when:

1) A bpf program uses bpf_probe_read_kernel() to read from the vsyscall
page and invokes copy_from_kernel_nofault() which in turn calls
__get_user_asm().

2) Because the vsyscall page address is not readable from kernel space,
a page fault exception is triggered accordingly.

3) handle_page_fault() considers the vsyscall page address as a user
space address instead of a kernel space address. This results in the
fix-up setup by bpf not being applied and a page_fault_oops() is invoked
due to SMAP.

Considering handle_page_fault() has already considered the vsyscall page
address as a userspace address, fix the problem by disallowing vsyscall
page read for copy_from_kernel_nofault().

Originally-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: syzbot+72aa0161922eba61b50e@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/CAG48ez06TZft=ATH1qh2c5mpS5BT8UakwNkzi6nvK5_djC-4Nw@mail.gmail.com
Reported-by: xingwei lee <xrivendell7@gmail.com>
Closes: https://lore.kernel.org/bpf/CABOYnLynjBoFZOf3Z4BhaZkc5hx_kHfsjiW+UWLoB=w33LvScw@mail.gmail.com
Signed-off-by: Hou Tao <houtao1@huawei.com>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240202103935.3154011-3-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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3 participants