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This reverts commit f35b5d7d676e59e401690b678cd3cfec5e785c23.
It has been reported to cause huge performance regressions on some loads
(will-it-scale.per_process_ops, but also building the kernel with
clang).
The commit did speed up gcc builds by a small amount, so it's not an
unambiguous regression, but until the big regressions are understood,
let's revert it.
Reported-by: kernel test robot <yujie.liu@intel.com>
Link: https://lore.kernel.org/r/202210181535.7144dd15-yujie.liu@intel.com
Reported-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/lkml/Y1DNQaoPWxE%2BrGce@dev-arch.thelio-3990X/
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently tpm transactions are executed unconditionally in
tpm_pm_suspend() function, which may lead to races with other tpm
accessors in the system.
Specifically, the hw_random tpm driver makes use of tpm_get_random(),
and this function is called in a loop from a kthread, which means it's
not frozen alongside userspace, and so can race with the work done
during system suspend:
tpm tpm0: tpm_transmit: tpm_recv: error -52
tpm tpm0: invalid TPM_STS.x 0xff, dumping stack for forensics
CPU: 0 PID: 1 Comm: init Not tainted 6.1.0-rc5+ #135
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-20220807_005459-localhost 04/01/2014
Call Trace:
tpm_tis_status.cold+0x19/0x20
tpm_transmit+0x13b/0x390
tpm_transmit_cmd+0x20/0x80
tpm1_pm_suspend+0xa6/0x110
tpm_pm_suspend+0x53/0x80
__pnp_bus_suspend+0x35/0xe0
__device_suspend+0x10f/0x350
Fix this by calling tpm_try_get_ops(), which itself is a wrapper around
tpm_chip_start(), but takes the appropriate mutex.
Signed-off-by: Jan Dabros <jsd@semihalf.com>
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Jason A. Donenfeld <Jason@zx2c4.com>
Tested-by: Vlastimil Babka <vbabka@suse.cz>
Link: https://lore.kernel.org/all/c5ba47ef-393f-1fba-30bd-1230d1b4b592@suse.cz/
Cc: stable@vger.kernel.org
Fixes: e891db1a18bf ("tpm: turn on TPM on suspend for TPM 1.x")
[Jason: reworked commit message, added metadata]
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull perf fix from Borislav Petkov:
- Fix a use-after-free case where the perf pending task callback would
see an already freed event
* tag 'perf_urgent_for_v6.1_rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Fix perf_pending_task() UaF
Pull timer fix from Borislav Petkov:
- Revert a fix to RISC-V timers supposed to address an uncertainty
whether clock events are received during S3 or not which locks up
other RISC-V platforms. The issue will be fixed differently later.
* tag 'timers_urgent_for_v6.1_rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "clocksource/drivers/riscv: Events are stopped during CPU suspend"
Per syzbot it is possible for perf_pending_task() to run after the
event is free()'d. There are two related but distinct cases:
- the task_work was already queued before destroying the event;
- destroying the event itself queues the task_work.
The first cannot be solved using task_work_cancel() since
perf_release() itself might be called from a task_work (____fput),
which means the current->task_works list is already empty and
task_work_cancel() won't be able to find the perf_pending_task()
entry.
The simplest alternative is extending the perf_event lifetime to cover
the task_work.
The second is just silly, queueing a task_work while you know the
event is going away makes no sense and is easily avoided by
re-arranging how the event is marked STATE_DEAD and ensuring it goes
through STATE_OFF on the way down.
Reported-by: syzbot+9228d6098455bb209ec8@syzkaller.appspotmail.com
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Marco Elver <elver@google.com>
Pull powerpc fixes from Michael Ellerman:
- Fix oops in 32-bit BPF tail call tests
- Add missing declaration for machine_check_early_boot()
Thanks to Christophe Leroy and Naveen N. Rao.
* tag 'powerpc-6.1-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s: Add missing declaration for machine_check_early_boot()
powerpc/bpf/32: Fix Oops on tail call tests
This reverts commit 232ccac1bd9b5bfe73895f527c08623e7fa0752d.
On the subject of suspend, the RISC-V SBI spec states:
This does not cover whether any given events actually reach the hart or
not, just what the hart will do if it receives an event. On PolarFire
SoC, and potentially other SiFive based implementations, events from the
RISC-V timer do reach a hart during suspend. This is not the case for the
implementation on the Allwinner D1 - there timer events are not received
during suspend.
To fix this, the CLOCK_EVT_FEAT_C3STOP (mis)feature was enabled for the
timer driver - but this has broken both RCU stall detection and timers
generally on PolarFire SoC and potentially other SiFive based
implementations.
If an AXI read to the PCIe controller on PolarFire SoC times out, the
system will stall, however, with CLOCK_EVT_FEAT_C3STOP active, the system
just locks up without RCU stalling:
io scheduler mq-deadline registered
io scheduler kyber registered
microchip-pcie 2000000000.pcie: host bridge /soc/pcie@2000000000 ranges:
microchip-pcie 2000000000.pcie: MEM 0x2008000000..0x2087ffffff -> 0x0008000000
microchip-pcie 2000000000.pcie: sec error in pcie2axi buffer
microchip-pcie 2000000000.pcie: ded error in pcie2axi buffer
microchip-pcie 2000000000.pcie: axi read request error
microchip-pcie 2000000000.pcie: axi read timeout
microchip-pcie 2000000000.pcie: sec error in pcie2axi buffer
microchip-pcie 2000000000.pcie: ded error in pcie2axi buffer
microchip-pcie 2000000000.pcie: sec error in pcie2axi buffer
microchip-pcie 2000000000.pcie: ded error in pcie2axi buffer
microchip-pcie 2000000000.pcie: sec error in pcie2axi buffer
microchip-pcie 2000000000.pcie: ded error in pcie2axi buffer
Freeing initrd memory: 7332K
Similarly issues were reported with clock_nanosleep() - with a test app
that sleeps each cpu for 6, 5, 4, 3 ms respectively, HZ=250 & the blamed
commit in place, the sleep times are rounded up to the next jiffy:
== CPU: 1 == == CPU: 2 == == CPU: 3 == == CPU: 4 ==
Mean: 7.974992 Mean: 7.976534 Mean: 7.962591 Mean: 3.952179
Std Dev: 0.154374 Std Dev: 0.156082 Std Dev: 0.171018 Std Dev: 0.076193
Hi: 9.472000 Hi: 10.495000 Hi: 8.864000 Hi: 4.736000
Lo: 6.087000 Lo: 6.380000 Lo: 4.872000 Lo: 3.403000
Samples: 521 Samples: 521 Samples: 521 Samples: 521
Fortunately, the D1 has a second timer, which is "currently used in
preference to the RISC-V/SBI timer driver" so a revert here does not
hurt operation of D1 in its current form.
Ultimately, a DeviceTree property (or node) will be added to encode the
behaviour of the timers, but until then revert the addition of
CLOCK_EVT_FEAT_C3STOP.
Fixes: 232ccac1bd9b ("clocksource/drivers/riscv: Events are stopped during CPU suspend")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Acked-by: Samuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/linux-riscv/YzYTNQRxLr7Q9JR0@spud/
Link: https://github.com/riscv-non-isa/riscv-sbi-doc/issues/98/
Link: https://lore.kernel.org/linux-riscv/bf6d3b1f-f703-4a25-833e-972a44a04114@sholland.org/
Link: https://lore.kernel.org/r/20221122121620.3522431-1-conor.dooley@microchip.com
Some PMUs (notably the traditional hardware kind) have boundary issues
with the OS filter. Specifically, it is possible for
perf_event_attr::exclude_kernel=1 events to trigger in-kernel due to
SKID or errata.
This can upset the sigtrap logic some and trigger the WARN.
However, if this invalid sample is the first we must not loose the
SIGTRAP, OTOH if it is the second, it must not override the
pending_addr with a (possibly) invalid one.
Fixes: ca6c21327c6a ("perf: Fix missing SIGTRAPs")
Reported-by: Pengfei Xu <pengfei.xu@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Link: https://lkml.kernel.org/r/Y3hDYiXwRnJr8RYG@xpf.sh.intel.com
Pull input fix from Dmitry Torokhov:
- a fix for Raydium touchscreen driver to stop leaking memory when
sending commands to the chip
* tag 'input-for-v6.1-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: raydium_ts_i2c - fix memory leak in raydium_i2c_send()
There's no declaration for machine_check_early_boot(), which leads to a
build failure with W=1. Add one.
Fixes: 2f5182cffa43 ("powerpc/64s: early boot machine check handler")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221125132521.2167039-1-mpe@ellerman.id.au
The perf_event_attr::sigtrap functionality relies on data->addr being
set. However commit 7b0846301531 ("perf: Use sample_flags for addr")
changed this to only initialize data->addr when not 0.
Fixes: 7b0846301531 ("perf: Use sample_flags for addr")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/Y3426b4OimE%2FI5po%40hirez.programming.kicks-ass.net
Pull i2c fixes from Wolfram Sang:
"A power state fix in the core for ACPI devices, a regression fix
regarding bus recovery for the cadence driver, a DMA handling fix for
the imx driver, and two error path fixes (npcm7xx and qcom-geni)"
* tag 'i2c-for-6.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: imx: Only DMA messages with I2C_M_DMA_SAFE flag set
i2c: qcom-geni: fix error return code in geni_i2c_gpi_xfer
i2c: cadence: Fix regression with bus recovery
i2c: Restore initial power state if probe fails
i2c: npcm7xx: Fix error handling in npcm_i2c_init()
There is a kmemleak when test the raydium_i2c_ts with bpf mock device:
unreferenced object 0xffff88812d3675a0 (size 8):
comm "python3", pid 349, jiffies 4294741067 (age 95.695s)
hex dump (first 8 bytes):
11 0e 10 c0 01 00 04 00 ........
backtrace:
[<0000000068427125>] __kmalloc+0x46/0x1b0
[<0000000090180f91>] raydium_i2c_send+0xd4/0x2bf [raydium_i2c_ts]
[<000000006e631aee>] raydium_i2c_initialize.cold+0xbc/0x3e4 [raydium_i2c_ts]
[<00000000dc6fcf38>] raydium_i2c_probe+0x3cd/0x6bc [raydium_i2c_ts]
[<00000000a310de16>] i2c_device_probe+0x651/0x680
[<00000000f5a96bf3>] really_probe+0x17c/0x3f0
[<00000000096ba499>] __driver_probe_device+0xe3/0x170
[<00000000c5acb4d9>] driver_probe_device+0x49/0x120
[<00000000264fe082>] __device_attach_driver+0xf7/0x150
[<00000000f919423c>] bus_for_each_drv+0x114/0x180
[<00000000e067feca>] __device_attach+0x1e5/0x2d0
[<0000000054301fc2>] bus_probe_device+0x126/0x140
[<00000000aad93b22>] device_add+0x810/0x1130
[<00000000c086a53f>] i2c_new_client_device+0x352/0x4e0
[<000000003c2c248c>] of_i2c_register_device+0xf1/0x110
[<00000000ffec4177>] of_i2c_notify+0x100/0x160
unreferenced object 0xffff88812d3675c8 (size 8):
comm "python3", pid 349, jiffies 4294741070 (age 95.692s)
hex dump (first 8 bytes):
22 00 36 2d 81 88 ff ff ".6-....
backtrace:
[<0000000068427125>] __kmalloc+0x46/0x1b0
[<0000000090180f91>] raydium_i2c_send+0xd4/0x2bf [raydium_i2c_ts]
[<000000001d5c9620>] raydium_i2c_initialize.cold+0x223/0x3e4 [raydium_i2c_ts]
[<00000000dc6fcf38>] raydium_i2c_probe+0x3cd/0x6bc [raydium_i2c_ts]
[<00000000a310de16>] i2c_device_probe+0x651/0x680
[<00000000f5a96bf3>] really_probe+0x17c/0x3f0
[<00000000096ba499>] __driver_probe_device+0xe3/0x170
[<00000000c5acb4d9>] driver_probe_device+0x49/0x120
[<00000000264fe082>] __device_attach_driver+0xf7/0x150
[<00000000f919423c>] bus_for_each_drv+0x114/0x180
[<00000000e067feca>] __device_attach+0x1e5/0x2d0
[<0000000054301fc2>] bus_probe_device+0x126/0x140
[<00000000aad93b22>] device_add+0x810/0x1130
[<00000000c086a53f>] i2c_new_client_device+0x352/0x4e0
[<000000003c2c248c>] of_i2c_register_device+0xf1/0x110
[<00000000ffec4177>] of_i2c_notify+0x100/0x160
After BANK_SWITCH command from i2c BUS, no matter success or error
happened, the tx_buf should be freed.
Fixes: 3b384bd6c3f2 ("Input: raydium_ts_i2c - do not split tx transactions")
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Link: https://lore.kernel.org/r/20221202103412.2120169-1-zhangxiaoxu5@huawei.com
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
test_bpf tail call tests end up as:
test_bpf: #0 Tail call leaf jited:1 85 PASS
test_bpf: #1 Tail call 2 jited:1 111 PASS
test_bpf: #2 Tail call 3 jited:1 145 PASS
test_bpf: #3 Tail call 4 jited:1 170 PASS
test_bpf: #4 Tail call load/store leaf jited:1 190 PASS
test_bpf: #5 Tail call load/store jited:1
BUG: Unable to handle kernel data access on write at 0xf1b4e000
Faulting instruction address: 0xbe86b710
Oops: Kernel access of bad area, sig: 11 [#1]
BE PAGE_SIZE=4K MMU=Hash PowerMac
Modules linked in: test_bpf(+)
CPU: 0 PID: 97 Comm: insmod Not tainted 6.1.0-rc4+ #195
Hardware name: PowerMac3,1 750CL 0x87210 PowerMac
NIP: be86b710 LR: be857e88 CTR: be86b704
REGS: f1b4df20 TRAP: 0300 Not tainted (6.1.0-rc4+)
MSR: 00009032 <EE,ME,IR,DR,RI> CR: 28008242 XER: 00000000
DAR: f1b4e000 DSISR: 42000000
GPR00: 00000001 f1b4dfe0 c11d2280 00000000 00000000 00000000 00000002 00000000
GPR08: f1b4e000 be86b704 f1b4e000 00000000 00000000 100d816a f2440000 fe73baa8
GPR16: f2458000 00000000 c1941ae4 f1fe2248 00000045 c0de0000 f2458030 00000000
GPR24: 000003e8 0000000f f2458000 f1b4dc90 3e584b46 00000000 f24466a0 c1941a00
NIP [be86b710] 0xbe86b710
LR [be857e88] __run_one+0xec/0x264 [test_bpf]
Call Trace:
[f1b4dfe0] [00000002] 0x2 (unreliable)
Instruction dump:
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
---[ end trace 0000000000000000 ]---
This is a tentative to write above the stack. The problem is encoutered
with tests added by commit 38608ee7b690 ("bpf, tests: Add load store
test case for tail call")
This happens because tail call is done to a BPF prog with a different
stack_depth. At the time being, the stack is kept as is when the caller
tail calls its callee. But at exit, the callee restores the stack based
on its own properties. Therefore here, at each run, r1 is erroneously
increased by 32 - 16 = 16 bytes.
This was done that way in order to pass the tail call count from caller
to callee through the stack. As powerpc32 doesn't have a red zone in
the stack, it was necessary the maintain the stack as is for the tail
call. But it was not anticipated that the BPF frame size could be
different.
Let's take a new approach. Use register r4 to carry the tail call count
during the tail call, and save it into the stack at function entry if
required. This means the input parameter must be in r3, which is more
correct as it is a 32 bits parameter, then tail call better match with
normal BPF function entry, the down side being that we move that input
parameter back and forth between r3 and r4. That can be optimised later.
Doing that also has the advantage of maximising the common parts between
tail calls and a normal function exit.
With the fix, tail call tests are now successfull:
test_bpf: #0 Tail call leaf jited:1 53 PASS
test_bpf: #1 Tail call 2 jited:1 115 PASS
test_bpf: #2 Tail call 3 jited:1 154 PASS
test_bpf: #3 Tail call 4 jited:1 165 PASS
test_bpf: #4 Tail call load/store leaf jited:1 101 PASS
test_bpf: #5 Tail call load/store jited:1 141 PASS
test_bpf: #6 Tail call error path, max count reached jited:1 994 PASS
test_bpf: #7 Tail call count preserved across function calls jited:1 140975 PASS
test_bpf: #8 Tail call error path, NULL target jited:1 110 PASS
test_bpf: #9 Tail call error path, index out of range jited:1 69 PASS
test_bpf: test_tail_calls: Summary: 10 PASSED, 0 FAILED, [10/10 JIT'ed]
Suggested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Fixes: 51c66ad849a7 ("powerpc/bpf: Implement extended BPF on PPC32")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/757acccb7fbfc78efa42dcf3c974b46678198905.1669278887.git.christophe.leroy@csgroup.eu
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