Linux kernel
============
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the problems which may result by upgrading your kernel.
code
Clone this repository
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Pull powerpc fixes from Michael Ellerman:
- Fix random crashes on some 32-bit CPUs by adding isync() after
locking/unlocking KUEP
- Fix intermittent crashes when loading modules with strict module RWX
- Fix a section mismatch introduce by a previous fix.
Thanks to Christophe Leroy, Fabiano Rosas, Laurent Vivier, Murilo
Opsfelder Araújo, Nathan Chancellor, and Stan Johnson.
h# -----BEGIN PGP SIGNATURE-----
* tag 'powerpc-5.14-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/mm: Fix set_memory_*() against concurrent accesses
powerpc/32s: Fix random crashes by adding isync() after locking/unlocking KUEP
powerpc/xive: Do not mark xive_request_ipi() as __init
Pull clk driver fixes from Stephen Boyd:
- Make the regulator state match the GDSC power domain state at boot on
Qualcomm SoCs so that the regulator isn't turned off inadvertently.
- Fix earlycon on i.MX6Q SoCs
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: qcom: gdsc: Ensure regulator init state matches GDSC state
clk: imx6q: fix uart earlycon unwork
Laurent reported that STRICT_MODULE_RWX was causing intermittent crashes
on one of his systems:
kernel tried to execute exec-protected page (c008000004073278) - exploit attempt? (uid: 0)
BUG: Unable to handle kernel instruction fetch
Faulting instruction address: 0xc008000004073278
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
Modules linked in: drm virtio_console fuse drm_panel_orientation_quirks ...
CPU: 3 PID: 44 Comm: kworker/3:1 Not tainted 5.14.0-rc4+ #12
Workqueue: events control_work_handler [virtio_console]
NIP: c008000004073278 LR: c008000004073278 CTR: c0000000001e9de0
REGS: c00000002e4ef7e0 TRAP: 0400 Not tainted (5.14.0-rc4+)
MSR: 800000004280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24002822 XER: 200400cf
...
NIP fill_queue+0xf0/0x210 [virtio_console]
LR fill_queue+0xf0/0x210 [virtio_console]
Call Trace:
fill_queue+0xb4/0x210 [virtio_console] (unreliable)
add_port+0x1a8/0x470 [virtio_console]
control_work_handler+0xbc/0x1e8 [virtio_console]
process_one_work+0x290/0x590
worker_thread+0x88/0x620
kthread+0x194/0x1a0
ret_from_kernel_thread+0x5c/0x64
Jordan, Fabiano & Murilo were able to reproduce and identify that the
problem is caused by the call to module_enable_ro() in do_init_module(),
which happens after the module's init function has already been called.
Our current implementation of change_page_attr() is not safe against
concurrent accesses, because it invalidates the PTE before flushing the
TLB and then installing the new PTE. That leaves a window in time where
there is no valid PTE for the page, if another CPU tries to access the
page at that time we see something like the fault above.
We can't simply switch to set_pte_at()/flush TLB, because our hash MMU
code doesn't handle a set_pte_at() of a valid PTE. See [1].
But we do have pte_update(), which replaces the old PTE with the new,
meaning there's no window where the PTE is invalid. And the hash MMU
version hash__pte_update() deals with synchronising the hash page table
correctly.
[1]: https://lore.kernel.org/linuxppc-dev/87y318wp9r.fsf@linux.ibm.com/
Fixes: 1f9ad21c3b38 ("powerpc/mm: Implement set_memory() routines")
Reported-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Murilo Opsfelder Araújo <muriloo@linux.ibm.com>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210818120518.3603172-1-mpe@ellerman.id.au
Pull char/misc driver fixes from Greg KH:
"Here are some small driver fixes for 5.14-rc7.
They consist of:
- revert for an interconnect patch that was found to have problems
- ipack tpci200 driver fixes for reported problems
- slimbus messaging and ngd fixes for reported problems
All are small and have been in linux-next for a while with no reported
issues"
* tag 'char-misc-5.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
ipack: tpci200: fix memory leak in the tpci200_register
ipack: tpci200: fix many double free issues in tpci200_pci_probe
slimbus: ngd: reset dma setup during runtime pm
slimbus: ngd: set correct device for pm
slimbus: messaging: check for valid transaction id
slimbus: messaging: start transaction ids from 1 instead of zero
Revert "interconnect: qcom: icc-rpmh: Add BCMs to commit list in pre_aggregate"
As GDSCs are registered and found to be already enabled gdsc_init()
ensures that 1) the kernel state matches the hardware state, and 2)
votable GDSCs are properly enabled from this master as well.
But as the (optional) supply regulator is enabled deep into
gdsc_toggle_logic(), which is only executed for votable GDSCs, the
kernel's state of the regulator might not match the hardware. The
regulator might be automatically turned off if no other users are
present or the next call to gdsc_disable() would cause an unbalanced
regulator_disable().
Given that the votable case deals with an already enabled GDSC, most of
gdsc_enable() and gdsc_toggle_logic() can be skipped. Reduce it to just
clearing the SW_COLLAPSE_MASK and enabling hardware control to simply
call regulator_enable() in both cases.
The enablement of hardware control seems to be an independent property
from the GDSC being enabled, so this is moved outside that conditional
segment.
Lastly, as the propagation of ALWAYS_ON to GENPD_FLAG_ALWAYS_ON needs to
happen regardless of the initial state this is grouped together with the
other sc->pd updates at the end of the function.
Cc: stable@vger.kernel.org
Fixes: 37416e554961 ("clk: qcom: gdsc: Handle GDSC regulator supplies")
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20210721224056.3035016-1-bjorn.andersson@linaro.org
[sboyd@kernel.org: Rephrase commit text]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Commit b5efec00b671 ("powerpc/32s: Move KUEP locking/unlocking in C")
removed the 'isync' instruction after adding/removing NX bit in user
segments. The reasoning behind this change was that when setting the
NX bit we don't mind it taking effect with delay as the kernel never
executes text from userspace, and when clearing the NX bit this is
to return to userspace and then the 'rfi' should synchronise the
context.
However, it looks like on book3s/32 having a hash page table, at least
on the G3 processor, we get an unexpected fault from userspace, then
this is followed by something wrong in the verification of MSR_PR
at end of another interrupt.
This is fixed by adding back the removed isync() following update
of NX bit in user segment registers. Only do it for cores with an
hash table, as 603 cores don't exhibit that problem and the two isync
increase ./null_syscall selftest by 6 cycles on an MPC 832x.
First problem: unexpected WARN_ON() for mysterious PROTFAULT
WARNING: CPU: 0 PID: 1660 at arch/powerpc/mm/fault.c:354 do_page_fault+0x6c/0x5b0
Modules linked in:
CPU: 0 PID: 1660 Comm: Xorg Not tainted 5.13.0-pmac-00028-gb3c15b60339a #40
NIP: c001b5c8 LR: c001b6f8 CTR: 00000000
REGS: e2d09e40 TRAP: 0700 Not tainted (5.13.0-pmac-00028-gb3c15b60339a)
MSR: 00021032 <ME,IR,DR,RI> CR: 42d04f30 XER: 20000000
GPR00: c000424c e2d09f00 c301b680 e2d09f40 0000001e 42000000 00cba028 00000000
GPR08: 08000000 48000010 c301b680 e2d09f30 22d09f30 00c1fff0 00cba000 a7b7ba4c
GPR16: 00000031 00000000 00000000 00000000 00000000 00000000 a7b7b0d0 00c5c010
GPR24: a7b7b64c a7b7d2f0 00000004 00000000 c1efa6c0 00cba02c 00000300 e2d09f40
NIP [c001b5c8] do_page_fault+0x6c/0x5b0
LR [c001b6f8] do_page_fault+0x19c/0x5b0
Call Trace:
[e2d09f00] [e2d09f04] 0xe2d09f04 (unreliable)
[e2d09f30] [c000424c] DataAccess_virt+0xd4/0xe4
--- interrupt: 300 at 0xa7a261dc
NIP: a7a261dc LR: a7a253bc CTR: 00000000
REGS: e2d09f40 TRAP: 0300 Not tainted (5.13.0-pmac-00028-gb3c15b60339a)
MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 228428e2 XER: 20000000
DAR: 00cba02c DSISR: 42000000
GPR00: a7a27448 afa6b0e0 a74c35c0 a7b7b614 0000001e a7b7b614 00cba028 00000000
GPR08: 00020fd9 00000031 00cb9ff8 a7a273b0 220028e2 00c1fff0 00cba000 a7b7ba4c
GPR16: 00000031 00000000 00000000 00000000 00000000 00000000 a7b7b0d0 00c5c010
GPR24: a7b7b64c a7b7d2f0 00000004 00000002 0000001e a7b7b614 a7b7aff4 00000030
NIP [a7a261dc] 0xa7a261dc
LR [a7a253bc] 0xa7a253bc
--- interrupt: 300
Instruction dump:
7c4a1378 810300a0 75278410 83820298 83a300a4 553b018c 551e0036 4082038c
2e1b0000 40920228 75280800 41820220 <0fe00000> 3b600000 41920214 81420594
Second problem: MSR PR is seen unset allthough the interrupt frame shows it set
kernel BUG at arch/powerpc/kernel/interrupt.c:458!
Oops: Exception in kernel mode, sig: 5 [#1]
BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 PowerMac
Modules linked in:
CPU: 0 PID: 1660 Comm: Xorg Tainted: G W 5.13.0-pmac-00028-gb3c15b60339a #40
NIP: c0011434 LR: c001629c CTR: 00000000
REGS: e2d09e70 TRAP: 0700 Tainted: G W (5.13.0-pmac-00028-gb3c15b60339a)
MSR: 00029032 <EE,ME,IR,DR,RI> CR: 42d09f30 XER: 00000000
GPR00: 00000000 e2d09f30 c301b680 e2d09f40 83440000 c44d0e68 e2d09e8c 00000000
GPR08: 00000002 00dc228a 00004000 e2d09f30 22d09f30 00c1fff0 afa6ceb4 00c26144
GPR16: 00c25fb8 00c26140 afa6ceb8 90000000 00c944d8 0000001c 00000000 00200000
GPR24: 00000000 000001fb afa6d1b4 00000001 00000000 a539a2a0 a530fd80 00000089
NIP [c0011434] interrupt_exit_kernel_prepare+0x10/0x70
LR [c001629c] interrupt_return+0x9c/0x144
Call Trace:
[e2d09f30] [c000424c] DataAccess_virt+0xd4/0xe4 (unreliable)
--- interrupt: 300 at 0xa09be008
NIP: a09be008 LR: a09bdfe8 CTR: a09bdfc0
REGS: e2d09f40 TRAP: 0300 Tainted: G W (5.13.0-pmac-00028-gb3c15b60339a)
MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 420028e2 XER: 20000000
DAR: a539a308 DSISR: 0a000000
GPR00: a7b90d50 afa6b2d0 a74c35c0 a0a8b690 a0a8b698 a5365d70 a4fa82a8 00000004
GPR08: 00000000 a09bdfc0 00000000 a5360000 a09bde7c 00c1fff0 afa6ceb4 00c26144
GPR16: 00c25fb8 00c26140 afa6ceb8 90000000 00c944d8 0000001c 00000000 00200000
GPR24: 00000000 000001fb afa6d1b4 00000001 00000000 a539a2a0 a530fd80 00000089
NIP [a09be008] 0xa09be008
LR [a09bdfe8] 0xa09bdfe8
--- interrupt: 300
Instruction dump:
80010024 83e1001c 7c0803a6 4bffff80 3bc00800 4bffffd0 486b42fd 4bffffcc
81430084 71480002 41820038 554a0462 <0f0a0000> 80620060 74630001 40820034
Fixes: b5efec00b671 ("powerpc/32s: Move KUEP locking/unlocking in C")
Cc: stable@vger.kernel.org # v5.13+
Reported-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4856f5574906e2aec0522be17bf3848a22b2cd0b.1629269345.git.christophe.leroy@csgroup.eu
Pull USB fix from Greg KH:
"Here is a single USB typec tcpm fix for a reported problem for
5.14-rc7. It showed up in 5.13 and resolves an issue that Hans found.
It has been in linux-next this week with no reported problems"
* tag 'usb-5.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: typec: tcpm: Fix VDMs sometimes not being forwarded to alt-mode drivers
Georgi writes:
interconnect fix for v5.14
This contains a revert for a patch that has been causing issues:
- Revert: qcom: rpmh: Add BCMs to commit list in pre_aggregate
Signed-off-by: Georgi Djakov <djakov@kernel.org>
* tag 'icc-5.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/djakov/icc:
Revert "interconnect: qcom: icc-rpmh: Add BCMs to commit list in pre_aggregate"
The earlycon depends on the bootloader setup UART clocks being retained.
There're actually two uart clocks (ipg, per) on MX6QDL,
but the 'Fixes' commit change to register only one which means
another clock may be disabled during booting phase
and result in the earlycon unwork.
Cc: stable@vger.kernel.org # v5.10+
Fixes: 379c9a24cc23 ("clk: imx: Fix reparenting of UARTs not associated with stdout")
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Link: https://lore.kernel.org/r/20210702085438.1988087-1-aisheng.dong@nxp.com
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Compiling ppc64le_defconfig with clang-14 shows a modpost warning:
WARNING: modpost: vmlinux.o(.text+0xa74e0): Section mismatch in
reference from the function xive_setup_cpu_ipi() to the function
.init.text:xive_request_ipi()
The function xive_setup_cpu_ipi() references
the function __init xive_request_ipi().
This is often because xive_setup_cpu_ipi lacks a __init
annotation or the annotation of xive_request_ipi is wrong.
xive_request_ipi() is called from xive_setup_cpu_ipi(), which is not
__init, so xive_request_ipi() should not be marked __init. Remove the
attribute so there is no more warning.
Fixes: cbc06f051c52 ("powerpc/xive: Do not skip CPU-less nodes when creating the IPIs")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210816185711.21563-1-nathan@kernel.org
Pull RISC-V fixes from Palmer Dabbelt:
- fix the sifive-l2-cache device tree bindings for json-schema
compatibility. This does not change the intended behavior of the
binding.
- avoid improperly freeing necessary resources during early boot.
* tag 'riscv-for-linus-5.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Fix a number of free'd resources in init_resources()
dt-bindings: sifive-l2-cache: Fix 'select' matching
Commit a20dcf53ea98 ("usb: typec: tcpm: Respond Not_Supported if no
snk_vdo"), stops tcpm_pd_data_request() calling tcpm_handle_vdm_request()
when port->nr_snk_vdo is not set. But the VDM might be intended for an
altmode-driver, in which case nr_snk_vdo does not matter.
This change breaks the forwarding of connector hotplug (HPD) events
for displayport altmode on devices which don't set nr_snk_vdo.
tcpm_pd_data_request() is the only caller of tcpm_handle_vdm_request(),
so we can move the nr_snk_vdo check to inside it, at which point we
have already looked up the altmode device so we can check for this too.
Doing this check here also ensures that vdm_state gets set to
VDM_STATE_DONE if it was VDM_STATE_BUSY, even if we end up with
responding with PD_MSG_CTRL_NOT_SUPP later.
Note that tcpm_handle_vdm_request() was already sending
PD_MSG_CTRL_NOT_SUPP in some circumstances, after moving the nr_snk_vdo
check the same error-path is now taken when that check fails. So that
we have only one error-path for this and not two. Replace the
tcpm_queue_message(PD_MSG_CTRL_NOT_SUPP) used by the existing error-path
with the more robust tcpm_pd_handle_msg() from the (now removed) second
error-path.
Fixes: a20dcf53ea98 ("usb: typec: tcpm: Respond Not_Supported if no snk_vdo")
Cc: stable <stable@vger.kernel.org>
Cc: Kyle Tso <kyletso@google.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Kyle Tso <kyletso@google.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210816154632.381968-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The error handling code in tpci200_register does not free interface_regs
allocated by ioremap and the current version of error handling code is
problematic.
Fix this by refactoring the error handling code and free interface_regs
when necessary.
Fixes: 43986798fd50 ("ipack: add error handling for ioremap_nocache")
Cc: stable@vger.kernel.org
Reported-by: Dongliang Mu <mudongliangabcd@gmail.com>
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Link: https://lore.kernel.org/r/20210810100323.3938492-2-mudongliangabcd@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>