tjh.dev
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Pull clk fix from Stephen Boyd:
"One-liner fix of a NULL pointer deref in the Allwinner clk driver"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: sunxi-ng: Fix H6 RTC clock definition
Pull x86 fixes from Borislav Petkov:
- Update the 'mitigations=' kernel param documentation
- Check the IBPB feature flag before enabling IBPB in firmware calls
because cloud vendors' fantasy when it comes to creating guest
configurations is unlimited
- Unexport sev_es_ghcb_hv_call() before 5.19 releases now that HyperV
doesn't need it anymore
- Remove dead CONFIG_* items
* tag 'x86_urgent_for_v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
docs/kernel-parameters: Update descriptions for "mitigations=" param with retbleed
x86/bugs: Do not enable IBPB at firmware entry when IBPB is not available
Revert "x86/sev: Expose sev_es_ghcb_hv_call() for use by HyperV"
x86/configs: Update configs in x86_debug.config
While RTC clock was added in H616 ccu_common list, it was not in H6
list. That caused invalid pointer dereference like this:
Unable to handle kernel NULL pointer dereference at virtual address 000000000000020c
Mem abort info:
ESR = 0x96000004
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
CM = 0, WnR = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=000000004d574000
[000000000000020c] pgd=0000000000000000, p4d=0000000000000000
Internal error: Oops: 96000004 [#1] PREEMPT SMP
CPU: 3 PID: 339 Comm: cat Tainted: G B 5.18.0-rc1+ #1352
Hardware name: Tanix TX6 (DT)
pstate: 00000005 (nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : ccu_gate_is_enabled+0x48/0x74
lr : ccu_gate_is_enabled+0x40/0x74
sp : ffff80000c0b76d0
x29: ffff80000c0b76d0 x28: 00000000016e3600 x27: 0000000000000000
x26: 0000000000000000 x25: 0000000000000002 x24: ffff00000952fe08
x23: ffff800009611400 x22: ffff00000952fe79 x21: 0000000000000000
x20: 0000000000000001 x19: ffff80000aad6f08 x18: 0000000000000000
x17: 2d2d2d2d2d2d2d2d x16: 2d2d2d2d2d2d2d2d x15: 2d2d2d2d2d2d2d2d
x14: 0000000000000000 x13: 00000000f2f2f2f2 x12: ffff700001816e89
x11: 1ffff00001816e88 x10: ffff700001816e88 x9 : dfff800000000000
x8 : ffff80000c0b7447 x7 : 0000000000000001 x6 : ffff700001816e88
x5 : ffff80000c0b7440 x4 : 0000000000000001 x3 : ffff800008935c50
x2 : dfff800000000000 x1 : 0000000000000000 x0 : 000000000000020c
Call trace:
ccu_gate_is_enabled+0x48/0x74
clk_core_is_enabled+0x7c/0x1c0
clk_summary_show_subtree+0x1dc/0x334
clk_summary_show_subtree+0x250/0x334
clk_summary_show_subtree+0x250/0x334
clk_summary_show_subtree+0x250/0x334
clk_summary_show_subtree+0x250/0x334
clk_summary_show+0x90/0xdc
seq_read_iter+0x248/0x6d4
seq_read+0x17c/0x1fc
full_proxy_read+0x90/0xf0
vfs_read+0xdc/0x28c
ksys_read+0xc8/0x174
__arm64_sys_read+0x44/0x5c
invoke_syscall+0x60/0x190
el0_svc_common.constprop.0+0x7c/0x160
do_el0_svc+0x38/0xa0
el0_svc+0x68/0x160
el0t_64_sync_handler+0x10c/0x140
el0t_64_sync+0x18c/0x190
Code: d1006260 97e5c981 785e8260 8b0002a0 (b9400000)
---[ end trace 0000000000000000 ]---
Fix that by adding rtc clock to H6 ccu_common list too.
Fixes: 38d321b61bda ("clk: sunxi-ng: h6-r: Add RTC gate clock")
Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://lore.kernel.org/r/20220719183725.2605141-1-jernej.skrabec@gmail.com
Reviewed-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull locking fix from Borislav Petkov:
- Avoid rwsem lockups in certain situations when handling the handoff
bit
* tag 'locking_urgent_for_v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/rwsem: Allow slowpath writer to ignore handoff bit if not set by first waiter
Updates descriptions for "mitigations=off" and "mitigations=auto,nosmt"
with the respective retbleed= settings.
Signed-off-by: Eiichi Tsukata <eiichi.tsukata@nutanix.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: corbet@lwn.net
Link: https://lore.kernel.org/r/20220728043907.165688-1-eiichi.tsukata@nutanix.com
The register address used for the clock gate register is the base
register address coming from first reg map (ie. the generic
clock registers) instead of the second reg map defining the clock
gate register.
Use the correct clock gate register address.
Fixes: 5ad5915dea00 ("clk: lan966x: Extend lan966x clock driver for clock gating support")
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Link: https://lore.kernel.org/r/20220704102845.168438-2-herve.codina@bootlin.com
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull EDAC fixes from Borislav Petkov:
- Relax the condition under which the DIMM label in ghes_edac is set in
order to accomodate an HPE BIOS which sets only the device but not
the bank
- Two forgotten fixes to synopsys_edac when handling error interrupts
* tag 'edac_urgent_for_v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/ghes: Set the DIMM label unconditionally
EDAC/synopsys: Re-enable the error interrupts on v3 hw
EDAC/synopsys: Use the correct register to disable the error interrupt on v3 hw
With commit d257cc8cb8d5 ("locking/rwsem: Make handoff bit handling more
consistent"), the writer that sets the handoff bit can be interrupted
out without clearing the bit if the wait queue isn't empty. This disables
reader and writer optimistic lock spinning and stealing.
Now if a non-first writer in the queue is somehow woken up or a new
waiter enters the slowpath, it can't acquire the lock. This is not the
case before commit d257cc8cb8d5 as the writer that set the handoff bit
will clear it when exiting out via the out_nolock path. This is less
efficient as the busy rwsem stays in an unlock state for a longer time.
In some cases, this new behavior may cause lockups as shown in [1] and
[2].
This patch allows a non-first writer to ignore the handoff bit if it
is not originally set or initiated by the first waiter. This patch is
shown to be effective in fixing the lockup problem reported in [1].
[1] https://lore.kernel.org/lkml/20220617134325.GC30825@techsingularity.net/
[2] https://lore.kernel.org/lkml/3f02975c-1a9d-be20-32cf-f1d8e3dfafcc@oracle.com/
Fixes: d257cc8cb8d5 ("locking/rwsem: Make handoff bit handling more consistent")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: John Donnelly <john.p.donnelly@oracle.com>
Tested-by: Mel Gorman <mgorman@techsingularity.net>
Link: https://lore.kernel.org/r/20220622200419.778799-1-longman@redhat.com
Some cloud hypervisors do not provide IBPB on very recent CPU processors,
including AMD processors affected by Retbleed.
Using IBPB before firmware calls on such systems would cause a GPF at boot
like the one below. Do not enable such calls when IBPB support is not
present.
EFI Variables Facility v0.08 2004-May-17
general protection fault, maybe for address 0x1: 0000 [#1] PREEMPT SMP NOPTI
CPU: 0 PID: 24 Comm: kworker/u2:1 Not tainted 5.19.0-rc8+ #7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
Workqueue: efi_rts_wq efi_call_rts
RIP: 0010:efi_call_rts
Code: e8 37 33 58 ff 41 bf 48 00 00 00 49 89 c0 44 89 f9 48 83 c8 01 4c 89 c2 48 c1 ea 20 66 90 b9 49 00 00 00 b8 01 00 00 00 31 d2 <0f> 30 e8 7b 9f 5d ff e8 f6 f8 ff ff 4c 89 f1 4c 89 ea 4c 89 e6 48
RSP: 0018:ffffb373800d7e38 EFLAGS: 00010246
RAX: 0000000000000001 RBX: 0000000000000006 RCX: 0000000000000049
RDX: 0000000000000000 RSI: ffff94fbc19d8fe0 RDI: ffff94fbc1b2b300
RBP: ffffb373800d7e70 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000000b R11: 000000000000000b R12: ffffb3738001fd78
R13: ffff94fbc2fcfc00 R14: ffffb3738001fd80 R15: 0000000000000048
FS: 0000000000000000(0000) GS:ffff94fc3da00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff94fc30201000 CR3: 000000006f610000 CR4: 00000000000406f0
Call Trace:
<TASK>
? __wake_up
process_one_work
worker_thread
? rescuer_thread
kthread
? kthread_complete_and_exit
ret_from_fork
</TASK>
Modules linked in:
Fixes: 28a99e95f55c ("x86/amd: Use IBPB for firmware calls")
Reported-by: Dimitri John Ledkov <dimitri.ledkov@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220728122602.2500509-1-cascardo@canonical.com
Maintainers of the directory Documentation/devicetree/bindings/clock
are also the maintainers of the corresponding directory in
include/dt-bindings/clock.
Add the file entry for include/dt-bindings/clock to the appropriate
section in MAINTAINERS.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/r/20220613085100.402-1-lukas.bulwahn@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull ARM fixes from Russell King:
"Last set of ARM fixes for 5.19:
- fix for MAX_DMA_ADDRESS overflow
- fix for find_*_bit performing an out of bounds memory access"
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: findbit: fix overflowing offset
ARM: 9216/1: Fix MAX_DMA_ADDRESS overflow
The commit
cb51a371d08e ("EDAC/ghes: Setup DIMM label from DMI and use it in error reports")
enforced that both the bank and device strings passed to
dimm_setup_label() are not NULL.
However, there are BIOSes, for example on a
HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 03/15/2019
which don't populate both strings:
Handle 0x0020, DMI type 17, 84 bytes
Memory Device
Array Handle: 0x0013
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 32 GB
Form Factor: DIMM
Set: None
Locator: PROC 1 DIMM 1 <===== device
Bank Locator: Not Specified <===== bank
This results in a buffer overflow because ghes_edac_register() calls
strlen() on an uninitialized label, which had non-zero values left over
from krealloc_array():
detected buffer overflow in __fortify_strlen
------------[ cut here ]------------
kernel BUG at lib/string_helpers.c:983!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 1 Comm: swapper/0 Tainted: G I 5.18.6-200.fc36.x86_64 #1
Hardware name: HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 03/15/2019
RIP: 0010:fortify_panic
...
Call Trace:
<TASK>
ghes_edac_register.cold
ghes_probe
platform_probe
really_probe
__driver_probe_device
driver_probe_device
__driver_attach
? __device_attach_driver
bus_for_each_dev
bus_add_driver
driver_register
acpi_ghes_init
acpi_init
? acpi_sleep_proc_init
do_one_initcall
The label contains garbage because the commit in Fixes reallocs the
DIMMs array while scanning the system but doesn't clear the newly
allocated memory.
Change dimm_setup_label() to always initialize the label to fix the
issue. Set it to the empty string in case BIOS does not provide both
bank and device so that ghes_edac_register() can keep the default label
given by edac_mc_alloc_dimms().
[ bp: Rewrite commit message. ]
Fixes: b9cae27728d1f ("EDAC/ghes: Scan the system once on driver init")
Co-developed-by: Robert Richter <rric@kernel.org>
Signed-off-by: Robert Richter <rric@kernel.org>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Robert Elliott <elliott@hpe.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220719220124.760359-1-toshi.kani@hpe.com
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