When CONFIG_FSL_PMC is set to n, no value is assigned to cpu_up_prepare
in the mpc85xx_pm_ops structure. As a result, oops is triggered in
smp_85xx_start_cpu().
smp: Bringing up secondary CPUs ...
kernel tried to execute user page (0) - exploit attempt? (uid: 0)
BUG: Unable to handle kernel instruction fetch (NULL pointer?)
Faulting instruction address: 0x00000000
Oops: Kernel access of bad area, sig: 11 [#1]
...
NIP [00000000] 0x0
LR [c0021d2c] smp_85xx_kick_cpu+0xe8/0x568
Call Trace:
[c1051da8] [c0021cb8] smp_85xx_kick_cpu+0x74/0x568 (unreliable)
[c1051de8] [c0011460] __cpu_up+0xc0/0x228
[c1051e18] [c0031bbc] bringup_cpu+0x30/0x224
[c1051e48] [c0031f3c] cpu_up.constprop.0+0x180/0x33c
[c1051e88] [c00322e8] bringup_nonboot_cpus+0x88/0xc8
[c1051eb8] [c07e67bc] smp_init+0x30/0x78
[c1051ed8] [c07d9e28] kernel_init_freeable+0x118/0x2a8
[c1051f18] [c00032d8] kernel_init+0x14/0x124
[c1051f38] [c0010278] ret_from_kernel_thread+0x14/0x1c
Fixes: c45361abb9 ("powerpc/85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n")
Reported-by: Martin Kennedy <hurricos@gmail.com>
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Tested-by: Martin Kennedy <hurricos@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211126041153.16926-1-nixiaoming@huawei.com
These aren't necessarily POWER9 only, and it's not to say some new
vulnerability may not get discovered on other processors for which
we would like the flexibility of having the workaround enabled by
firmware.
Remove the restriction that the workarounds only apply to POWER9.
However POWER7 and POWER8 are not affected, and they may not have
older firmware that does not advertise this, so clear these workarounds
manually.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
[mpe: Incorporate changes from Nick, reword comment slightly.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210503130243.891868-5-npiggin@gmail.com
for_each_node_by_name performs an of_node_get on each iteration, so
a break out of the loop requires an of_node_put.
A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):
// <smpl>
@@
expression e,e1;
local idexpression n;
@@
for_each_node_by_name(n, e1) {
... when != of_node_put(n)
when != e = n
(
return n;
|
+ of_node_put(n);
? return ...;
)
...
}
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1448051604-25256-7-git-send-email-Julia.Lawall@lip6.fr
for_each_compatible_node performs an of_node_get on each iteration, so
a break out of the loop requires an of_node_put.
A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):
// <smpl>
@@
local idexpression n;
expression e;
@@
for_each_compatible_node(n,...) {
...
(
of_node_put(n);
|
e = n
|
+ of_node_put(n);
? break;
)
...
}
... when != n
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1448051604-25256-4-git-send-email-Julia.Lawall@lip6.fr
for_each_compatible_node performs an of_node_get on each iteration, so
a break out of the loop requires an of_node_put.
A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):
// <smpl>
@@
expression e;
local idexpression n;
@@
@@
local idexpression n;
expression e;
@@
for_each_compatible_node(n,...) {
...
(
of_node_put(n);
|
e = n
|
+ of_node_put(n);
? break;
)
...
}
... when != n
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1448051604-25256-2-git-send-email-Julia.Lawall@lip6.fr
There is a possibility of having just one DMA window available with
a limited capacity which the existing code does not handle that well.
If the window is big enough for the system RAM but less than
MAX_PHYSMEM_BITS (which we want when persistent memory is present),
we create 1:1 window and leave persistent memory without DMA.
This disables 1:1 mapping entirely if there is persistent memory and
either:
- the huge DMA window does not cover the entire address space;
- the default DMA window is removed.
This relies on reverted 54fc3c681d
("powerpc/pseries/ddw: Extend upper limit for huge DMA window for persistent memory")
to return the actual amount RAM in ddw_memory_hotplug_max() (posted
separately).
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211108040320.3857636-4-aik@ozlabs.ru
Commit 5d354dc35e ("powerpc/83xx/mpc8349emitx: Make
mcu_gpiochip_remove() return void") removed the usage of the variable
ret, but failed to remove the variable itself, resulting in:
arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c: In function ‘mcu_remove’:
arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c:189:6: error: unused variable ‘ret’ [-Werror=unused-variable]
189 | int ret;
| ^~~
So remove the variable now.
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211110110739.1072634-1-u.kleine-koenig@pengutronix.de
Pull cxl updates from Dan Williams:
"More preparation and plumbing work in the CXL subsystem.
From an end user perspective the highlight here is lighting up the CXL
Persistent Memory related commands (label read / write) with the
generic ioctl() front-end in LIBNVDIMM.
Otherwise, the ability to instantiate new persistent and volatile
memory regions is still on track for v5.17.
Summary:
- Fix support for platforms that do not enumerate every ACPI0016 (CXL
Host Bridge) in the CHBS (ACPI Host Bridge Structure).
- Introduce a common pci_find_dvsec_capability() helper, clean up
open coded implementations in various drivers.
- Add 'cxl_test' for regression testing CXL subsystem ABIs.
'cxl_test' is a module built from tools/testing/cxl/ that mocks up
a CXL topology to augment the nascent support for emulation of CXL
devices in QEMU.
- Convert libnvdimm to use the uuid API.
- Complete the definition of CXL namespace labels in libnvdimm.
- Tunnel libnvdimm label operations from nd_ioctl() back to the CXL
mailbox driver. Enable 'ndctl {read,write}-labels' for CXL.
- Continue to sort and refactor functionality into distinct driver
and core-infrastructure buckets. For example, mailbox handling is
now a generic core capability consumed by the PCI and cxl_test
drivers"
* tag 'cxl-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (34 commits)
ocxl: Use pci core's DVSEC functionality
cxl/pci: Use pci core's DVSEC functionality
PCI: Add pci_find_dvsec_capability to find designated VSEC
cxl/pci: Split cxl_pci_setup_regs()
cxl/pci: Add @base to cxl_register_map
cxl/pci: Make more use of cxl_register_map
cxl/pci: Remove pci request/release regions
cxl/pci: Fix NULL vs ERR_PTR confusion
cxl/pci: Remove dev_dbg for unknown register blocks
cxl/pci: Convert register block identifiers to an enum
cxl/acpi: Do not fail cxl_acpi_probe() based on a missing CHBS
cxl/pci: Disambiguate cxl_pci further from cxl_mem
Documentation/cxl: Add bus internal docs
cxl/core: Split decoder setup into alloc + add
tools/testing/cxl: Introduce a mock memory device + driver
cxl/mbox: Move command definitions to common location
cxl/bus: Populate the target list at decoder create
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy
cxl/pmem: Add support for multiple nvdimm-bridge objects
cxl/pmem: Translate NVDIMM label commands to CXL label commands
...
Pull pci updates from Bjorn Helgaas:
"Enumeration:
- Conserve IRQs by setting up portdrv IRQs only when there are users
(Jan Kiszka)
- Rework and simplify _OSC negotiation for control of PCIe features
(Joerg Roedel)
- Remove struct pci_dev.driver pointer since it's redundant with the
struct device.driver pointer (Uwe Kleine-König)
Resource management:
- Coalesce contiguous host bridge apertures from _CRS to accommodate
BARs that cover more than one aperture (Kai-Heng Feng)
Sysfs:
- Check CAP_SYS_ADMIN before parsing user input (Krzysztof
Wilczyński)
- Return -EINVAL consistently from "store" functions (Krzysztof
Wilczyński)
- Use sysfs_emit() in endpoint "show" functions to avoid buffer
overruns (Kunihiko Hayashi)
PCIe native device hotplug:
- Ignore Link Down/Up caused by resets during error recovery so
endpoint drivers can remain bound to the device (Lukas Wunner)
Virtualization:
- Avoid bus resets on Atheros QCA6174, where they hang the device
(Ingmar Klein)
- Work around Pericom PI7C9X2G switch packet drop erratum by using
store and forward mode instead of cut-through (Nathan Rossi)
- Avoid trying to enable AtomicOps on VFs; the PF setting applies to
all VFs (Selvin Xavier)
MSI:
- Document that /sys/bus/pci/devices/.../irq contains the legacy INTx
interrupt or the IRQ of the first MSI (not MSI-X) vector (Barry
Song)
VPD:
- Add pci_read_vpd_any() and pci_write_vpd_any() to access anywhere
in the possible VPD space; use these to simplify the cxgb3 driver
(Heiner Kallweit)
Peer-to-peer DMA:
- Add (not subtract) the bus offset when calculating DMA address
(Wang Lu)
ASPM:
- Re-enable LTR at Downstream Ports so they don't report Unsupported
Requests when reset or hot-added devices send LTR messages
(Mingchuang Qiao)
Apple PCIe controller driver:
- Add driver for Apple M1 PCIe controller (Alyssa Rosenzweig, Marc
Zyngier)
Cadence PCIe controller driver:
- Return success when probe succeeds instead of falling into error
path (Li Chen)
HiSilicon Kirin PCIe controller driver:
- Reorganize PHY logic and add support for external PHY drivers
(Mauro Carvalho Chehab)
- Support PERST# GPIOs for HiKey970 external PEX 8606 bridge (Mauro
Carvalho Chehab)
- Add Kirin 970 support (Mauro Carvalho Chehab)
- Make driver removable (Mauro Carvalho Chehab)
Intel VMD host bridge driver:
- If IOMMU supports interrupt remapping, leave VMD MSI-X remapping
enabled (Adrian Huang)
- Number each controller so we can tell them apart in
/proc/interrupts (Chunguang Xu)
- Avoid building on UML because VMD depends on x86 bare metal APIs
(Johannes Berg)
Marvell Aardvark PCIe controller driver:
- Define macros for PCI_EXP_DEVCTL_PAYLOAD_* (Pali Rohár)
- Set Max Payload Size to 512 bytes per Marvell spec (Pali Rohár)
- Downgrade PIO Response Status messages to debug level (Marek Behún)
- Preserve CRS SV (Config Request Retry Software Visibility) bit in
emulated Root Control register (Pali Rohár)
- Fix issue in configuring reference clock (Pali Rohár)
- Don't clear status bits for masked interrupts (Pali Rohár)
- Don't mask unused interrupts (Pali Rohár)
- Avoid code repetition in advk_pcie_rd_conf() (Marek Behún)
- Retry config accesses on CRS response (Pali Rohár)
- Simplify emulated Root Capabilities initialization (Pali Rohár)
- Fix several link training issues (Pali Rohár)
- Fix link-up checking via LTSSM (Pali Rohár)
- Fix reporting of Data Link Layer Link Active (Pali Rohár)
- Fix emulation of W1C bits (Marek Behún)
- Fix MSI domain .alloc() method to return zero on success (Marek
Behún)
- Read entire 16-bit MSI vector in MSI handler, not just low 8 bits
(Marek Behún)
- Clear Root Port I/O Space, Memory Space, and Bus Master Enable bits
at startup; PCI core will set those as necessary (Pali Rohár)
- When operating as a Root Port, set class code to "PCI Bridge"
instead of the default "Mass Storage Controller" (Pali Rohár)
- Add emulation for PCI_BRIDGE_CTL_BUS_RESET since aardvark doesn't
implement this per spec (Pali Rohár)
- Add emulation of option ROM BAR since aardvark doesn't implement
this per spec (Pali Rohár)
MediaTek MT7621 PCIe controller driver:
- Add MediaTek MT7621 PCIe host controller driver and DT binding
(Sergio Paracuellos)
Qualcomm PCIe controller driver:
- Add SC8180x compatible string (Bjorn Andersson)
- Add endpoint controller driver and DT binding (Manivannan
Sadhasivam)
- Restructure to use of_device_get_match_data() (Prasad Malisetty)
- Add SC7280-specific pcie_1_pipe_clk_src handling (Prasad Malisetty)
Renesas R-Car PCIe controller driver:
- Remove unnecessary includes (Geert Uytterhoeven)
Rockchip DesignWare PCIe controller driver:
- Add DT binding (Simon Xue)
Socionext UniPhier Pro5 controller driver:
- Serialize INTx masking/unmasking (Kunihiko Hayashi)
Synopsys DesignWare PCIe controller driver:
- Run dwc .host_init() method before registering MSI interrupt
handler so we can deal with pending interrupts left by bootloader
(Bjorn Andersson)
- Clean up Kconfig dependencies (Andy Shevchenko)
- Export symbols to allow more modular drivers (Luca Ceresoli)
TI DRA7xx PCIe controller driver:
- Allow host and endpoint drivers to be modules (Luca Ceresoli)
- Enable external clock if present (Luca Ceresoli)
TI J721E PCIe driver:
- Disable PHY when probe fails after initializing it (Christophe
JAILLET)
MicroSemi Switchtec management driver:
- Return error to application when command execution fails because an
out-of-band reset has cleared the device BARs, Memory Space Enable,
etc (Kelvin Cao)
- Fix MRPC error status handling issue (Kelvin Cao)
- Mask out other bits when reading of management VEP instance ID
(Kelvin Cao)
- Return EOPNOTSUPP instead of ENOTSUPP from sysfs show functions
(Kelvin Cao)
- Add check of event support (Logan Gunthorpe)
Miscellaneous:
- Remove unused pci_pool wrappers, which have been replaced by
dma_pool (Cai Huoqing)
- Use 'unsigned int' instead of bare 'unsigned' (Krzysztof
Wilczyński)
- Use kstrtobool() directly, sans strtobool() wrapper (Krzysztof
Wilczyński)
- Fix some sscanf(), sprintf() format mismatches (Krzysztof
Wilczyński)
- Update PCI subsystem information in MAINTAINERS (Krzysztof
Wilczyński)
- Correct some misspellings (Krzysztof Wilczyński)"
* tag 'pci-v5.16-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (137 commits)
PCI: Add ACS quirk for Pericom PI7C9X2G switches
PCI: apple: Configure RID to SID mapper on device addition
iommu/dart: Exclude MSI doorbell from PCIe device IOVA range
PCI: apple: Implement MSI support
PCI: apple: Add INTx and per-port interrupt support
PCI: kirin: Allow removing the driver
PCI: kirin: De-init the dwc driver
PCI: kirin: Disable clkreq during poweroff sequence
PCI: kirin: Move the power-off code to a common routine
PCI: kirin: Add power_off support for Kirin 960 PHY
PCI: kirin: Allow building it as a module
PCI: kirin: Add MODULE_* macros
PCI: kirin: Add Kirin 970 compatible
PCI: kirin: Support PERST# GPIOs for HiKey970 external PEX 8606 bridge
PCI: apple: Set up reference clocks when probing
PCI: apple: Add initial hardware bring-up
PCI: of: Allow matching of an interrupt-map local to a PCI device
of/irq: Allow matching of an interrupt-map local to an interrupt controller
irqdomain: Make of_phandle_args_to_fwspec() generally available
PCI: Do not enable AtomicOps on VFs
...
Merge misc updates from Andrew Morton:
"257 patches.
Subsystems affected by this patch series: scripts, ocfs2, vfs, and
mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache,
gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc,
pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools,
memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm,
vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram,
cleanups, kfence, and damon)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits)
mm/damon: remove return value from before_terminate callback
mm/damon: fix a few spelling mistakes in comments and a pr_debug message
mm/damon: simplify stop mechanism
Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions
Docs/admin-guide/mm/damon/start: simplify the content
Docs/admin-guide/mm/damon/start: fix a wrong link
Docs/admin-guide/mm/damon/start: fix wrong example commands
mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on
mm/damon: remove unnecessary variable initialization
Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM
mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM)
selftests/damon: support watermarks
mm/damon/dbgfs: support watermarks
mm/damon/schemes: activate schemes based on a watermarks mechanism
tools/selftests/damon: update for regions prioritization of schemes
mm/damon/dbgfs: support prioritization weights
mm/damon/vaddr,paddr: support pageout prioritization
mm/damon/schemes: prioritize regions within the quotas
mm/damon/selftests: support schemes quotas
mm/damon/dbgfs: support quotas of schemes
...
Pull powerpc updates from Michael Ellerman:
- Enable STRICT_KERNEL_RWX for Freescale 85xx platforms.
- Activate CONFIG_STRICT_KERNEL_RWX by default, while still allowing it
to be disabled.
- Add support for out-of-line static calls on 32-bit.
- Fix oopses doing bpf-to-bpf calls when STRICT_KERNEL_RWX is enabled.
- Fix boot hangs on e5500 due to stale value in ESR passed to
do_page_fault().
- Fix several bugs on pseries in handling of device tree cache
information for hotplugged CPUs, and/or during partition migration.
- Various other small features and fixes.
Thanks to Alexey Kardashevskiy, Alistair Popple, Anatolij Gustschin,
Andrew Donnellan, Athira Rajeev, Bixuan Cui, Bjorn Helgaas, Cédric Le
Goater, Christophe Leroy, Daniel Axtens, Daniel Henrique Barboza, Denis
Kirjanov, Fabiano Rosas, Frederic Barrat, Gustavo A. R. Silva, Hari
Bathini, Jacques de Laval, Joel Stanley, Kai Song, Kajol Jain, Laurent
Vivier, Leonardo Bras, Madhavan Srinivasan, Nathan Chancellor, Nathan
Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Niklas
Schnelle, Oliver O'Halloran, Rob Herring, Russell Currey, Srikar
Dronamraju, Stan Johnson, Tyrel Datwyler, Uwe Kleine-König, Vasant
Hegde, Wan Jiabing, and Xiaoming Ni,
* tag 'powerpc-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (73 commits)
powerpc/8xx: Fix Oops with STRICT_KERNEL_RWX without DEBUG_RODATA_TEST
powerpc/32e: Ignore ESR in instruction storage interrupt handler
powerpc/powernv/prd: Unregister OPAL_MSG_PRD2 notifier during module unload
powerpc: Don't provide __kernel_map_pages() without ARCH_SUPPORTS_DEBUG_PAGEALLOC
MAINTAINERS: Update powerpc KVM entry
powerpc/xmon: fix task state output
powerpc/44x/fsp2: add missing of_node_put
powerpc/dcr: Use cmplwi instead of 3-argument cmpli
KVM: PPC: Tick accounting should defer vtime accounting 'til after IRQ handling
powerpc/security: Use a mutex for interrupt exit code patching
powerpc/83xx/mpc8349emitx: Make mcu_gpiochip_remove() return void
powerpc/fsl_booke: Fix setting of exec flag when setting TLBCAMs
powerpc/book3e: Fix set_memory_x() and set_memory_nx()
powerpc/nohash: Fix __ptep_set_access_flags() and ptep_set_wrprotect()
powerpc/bpf: Fix write protecting JIT code
selftests/powerpc: Use date instead of EPOCHSECONDS in mitigation-patching.sh
powerpc/64s/interrupt: Fix check_return_regs_valid() false positive
powerpc/boot: Set LC_ALL=C in wrapper script
powerpc/64s: Default to 64K pages for 64 bit book3s
Revert "powerpc/audit: Convert powerpc to AUDIT_ARCH_COMPAT_GENERIC"
...
Pull generic confidential computing updates from Borislav Petkov:
"Add an interface called cc_platform_has() which is supposed to be used
by confidential computing solutions to query different aspects of the
system.
The intent behind it is to unify testing of such aspects instead of
having each confidential computing solution add its own set of tests
to code paths in the kernel, leading to an unwieldy mess"
* tag 'x86_cc_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
treewide: Replace the use of mem_encrypt_active() with cc_platform_has()
x86/sev: Replace occurrences of sev_es_active() with cc_platform_has()
x86/sev: Replace occurrences of sev_active() with cc_platform_has()
x86/sme: Replace occurrences of sme_active() with cc_platform_has()
powerpc/pseries/svm: Add a powerpc version of cc_platform_has()
x86/sev: Add an x86 version of cc_platform_has()
arch/cc: Introduce a function to check for confidential computing features
x86/ioremap: Selectively build arch override encryption functions
Pull block updates from Jens Axboe:
- mq-deadline accounting improvements (Bart)
- blk-wbt timer fix (Andrea)
- Untangle the block layer includes (Christoph)
- Rework the poll support to be bio based, which will enable adding
support for polling for bio based drivers (Christoph)
- Block layer core support for multi-actuator drives (Damien)
- blk-crypto improvements (Eric)
- Batched tag allocation support (me)
- Request completion batching support (me)
- Plugging improvements (me)
- Shared tag set improvements (John)
- Concurrent queue quiesce support (Ming)
- Cache bdev in ->private_data for block devices (Pavel)
- bdev dio improvements (Pavel)
- Block device invalidation and block size improvements (Xie)
- Various cleanups, fixes, and improvements (Christoph, Jackie,
Masahira, Tejun, Yu, Pavel, Zheng, me)
* tag 'for-5.16/block-2021-10-29' of git://git.kernel.dk/linux-block: (174 commits)
blk-mq-debugfs: Show active requests per queue for shared tags
block: improve readability of blk_mq_end_request_batch()
virtio-blk: Use blk_validate_block_size() to validate block size
loop: Use blk_validate_block_size() to validate block size
nbd: Use blk_validate_block_size() to validate block size
block: Add a helper to validate the block size
block: re-flow blk_mq_rq_ctx_init()
block: prefetch request to be initialized
block: pass in blk_mq_tags to blk_mq_rq_ctx_init()
block: add rq_flags to struct blk_mq_alloc_data
block: add async version of bio_set_polled
block: kill DIO_MULTI_BIO
block: kill unused polling bits in __blkdev_direct_IO()
block: avoid extra iter advance with async iocb
block: Add independent access ranges support
blk-mq: don't issue request directly in case that current is to be blocked
sbitmap: silence data race warning
blk-cgroup: synchronize blkg creation against policy deactivation
block: refactor bio_iov_bvec_set()
block: add single bio async direct IO helper
...
The iommu_init_table() helper takes an address range to reserve in
the IOMMU table being initialized to exclude MMIO addresses, this is
useful if the window stretches far beyond 4GB (although wastes some TCEs).
At the moment the code searches for such MMIO32 range and fails if none
found which is considered a problem while it really is not: it is actually
better as this says there is no MMIO32 to reserve and we can use
usually wasted TCEs. Furthermore PHYP never actually allows creating
windows starting at busaddress=0 so this MMIO32 range is never useful.
This removes error exit and initializes the table with zero range if
no MMIO32 is detected.
Fixes: 381ceda88c ("powerpc/pseries/iommu: Make use of DDW for indirect mapping")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211020132315.2287178-5-aik@ozlabs.ru
At the moment this check is performed after we remove the default window
which is late and disallows to revert whatever changes enable_ddw()
has made to DMA windows.
This moves the check and error exit before removing the window.
This raised the message severity from "debug" to "warning" as this
should not happen in practice and cannot be triggered by the userspace.
Fixes: 381ceda88c ("powerpc/pseries/iommu: Make use of DDW for indirect mapping")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211020132315.2287178-4-aik@ozlabs.ru
On VMs with NX encryption, compression, and/or RNG offload, these
capabilities are described by nodes in the ibm,platform-facilities device
tree hierarchy:
$ tree -d /sys/firmware/devicetree/base/ibm,platform-facilities/
/sys/firmware/devicetree/base/ibm,platform-facilities/
├── ibm,compression-v1
├── ibm,random-v1
└── ibm,sym-encryption-v1
3 directories
The acceleration functions that these nodes describe are not disrupted by
live migration, not even temporarily.
But the post-migration ibm,update-nodes sequence firmware always sends
"delete" messages for this hierarchy, followed by an "add" directive to
reconstruct it via ibm,configure-connector (log with debugging statements
enabled in mobility.c):
mobility: removing node /ibm,platform-facilities/ibm,random-v1:4294967285
mobility: removing node /ibm,platform-facilities/ibm,compression-v1:4294967284
mobility: removing node /ibm,platform-facilities/ibm,sym-encryption-v1:4294967283
mobility: removing node /ibm,platform-facilities:4294967286
...
mobility: added node /ibm,platform-facilities:4294967286
Note we receive a single "add" message for the entire hierarchy, and what
we receive from the ibm,configure-connector sequence is the top-level
platform-facilities node along with its three children. The debug message
simply reports the parent node and not the whole subtree.
Also, significantly, the nodes added are almost completely equivalent to
the ones removed; even phandles are unchanged. ibm,shared-interrupt-pool in
the leaf nodes is the only property I've observed to differ, and Linux does
not use that. So in practice, the sum of update messages Linux receives for
this hierarchy is equivalent to minor property updates.
We succeed in removing the original hierarchy from the device tree. But the
vio bus code is ignorant of this, and does not unbind or relinquish its
references. The leaf nodes, still reachable through sysfs, of course still
refer to the now-freed ibm,platform-facilities parent node, which makes
use-after-free possible:
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 3 PID: 1706 at lib/refcount.c:25 refcount_warn_saturate+0x164/0x1f0
refcount_warn_saturate+0x160/0x1f0 (unreliable)
kobject_get+0xf0/0x100
of_node_get+0x30/0x50
of_get_parent+0x50/0xb0
of_fwnode_get_parent+0x54/0x90
fwnode_count_parents+0x50/0x150
fwnode_full_name_string+0x30/0x110
device_node_string+0x49c/0x790
vsnprintf+0x1c0/0x4c0
sprintf+0x44/0x60
devspec_show+0x34/0x50
dev_attr_show+0x40/0xa0
sysfs_kf_seq_show+0xbc/0x200
kernfs_seq_show+0x44/0x60
seq_read_iter+0x2a4/0x740
kernfs_fop_read_iter+0x254/0x2e0
new_sync_read+0x120/0x190
vfs_read+0x1d0/0x240
Moreover, the "new" replacement subtree is not correctly added to the
device tree, resulting in ibm,platform-facilities parent node without the
appropriate leaf nodes, and broken symlinks in the sysfs device hierarchy:
$ tree -d /sys/firmware/devicetree/base/ibm,platform-facilities/
/sys/firmware/devicetree/base/ibm,platform-facilities/
0 directories
$ cd /sys/devices/vio ; find . -xtype l -exec file {} +
./ibm,sym-encryption-v1/of_node: broken symbolic link to
../../../firmware/devicetree/base/ibm,platform-facilities/ibm,sym-encryption-v1
./ibm,random-v1/of_node: broken symbolic link to
../../../firmware/devicetree/base/ibm,platform-facilities/ibm,random-v1
./ibm,compression-v1/of_node: broken symbolic link to
../../../firmware/devicetree/base/ibm,platform-facilities/ibm,compression-v1
This is because add_dt_node() -> dlpar_attach_node() attaches only the
parent node returned from configure-connector, ignoring any children. This
should be corrected for the general case, but fixing that won't help with
the stale OF node references, which is the more urgent problem.
One way to address that would be to make the drivers respond to node
removal notifications, so that node references can be dropped
appropriately. But this would likely force the drivers to disrupt active
clients for no useful purpose: equivalent nodes are immediately re-added.
And recall that the acceleration capabilities described by the nodes remain
available throughout the whole process.
The solution I believe to be robust for this situation is to convert
remove+add of a node with an unchanged phandle to an update of the node's
properties in the Linux device tree structure. That would involve changing
and adding a fair amount of code, and may take several iterations to land.
Until that can be realized we have a confirmed use-after-free and the
possibility of memory corruption. So add a limited workaround that
discriminates on the node type, ignoring adds and removes. This should be
amenable to backporting in the meantime.
Fixes: 410bccf978 ("powerpc/pseries: Partition migration in the kernel")
Cc: stable@vger.kernel.org
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211020194703.2613093-1-nathanl@linux.ibm.com
(!ptr && !ptr->foo) strikes again. :)
The expression (!ptr && !ptr->foo) is bogus and in case ptr is NULL,
it leads to a NULL pointer dereference: ptr->foo.
Fix this by converting && to ||
This issue was detected with the help of Coccinelle, and audited and
fixed manually.
Fixes: 1a0d0d5ed5 ("powerpc/vas: Add platform specific user window operations")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211015050345.GA1161918@embeddedor
This comment likely refers to the obsolete DLPAR workflow where some
resource state transitions were driven more directly from user space
utilities, but it also seems to contradict itself: "Change isolate state to
Isolate [...]" is at odds with the preceding sentences, and it does not
relate at all to the code that follows.
Remove it to prevent confusion.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210927201933.76786-5-nathanl@linux.ibm.com
The core DLPAR code supports two actions (add and remove) and three
subtypes of action:
* By DRC index: the action is attempted on a single specified resource.
This is the usual case for processors.
* By indexed count: the action is attempted on a range of resources
beginning at the specified index. This is implemented only by the memory
DLPAR code.
* By count: the lower layer (CPU or memory) is responsible for locating the
specified number of resources to which the action can be applied.
I cannot find any evidence of the "by count" subtype being used by drmgr or
qemu for processors. And when I try to exercise this code, the add case
does not work:
$ ppc64_cpu --smt ; nproc
SMT=8
24
$ printf "cpu remove count 2" > /sys/kernel/dlpar
$ nproc
8
$ printf "cpu add count 2" > /sys/kernel/dlpar
-bash: printf: write error: Invalid argument
$ dmesg | tail -2
pseries-hotplug-cpu: Failed to find enough CPUs (1 of 2) to add
dlpar: Could not handle DLPAR request "cpu add count 2"
$ nproc
8
$ drmgr -c cpu -a -q 2 # this uses the by-index method
Validating CPU DLPAR capability...yes.
CPU 1
CPU 17
$ nproc
24
This is because find_drc_info_cpus_to_add() does not increment drc_index
appropriately during its search.
This is not hard to fix. But the _by_count() functions also have the
property that they attempt to roll back all prior operations if the entire
request cannot be satisfied, even though the rollback itself can encounter
errors. It's not possible to provide transaction-like behavior at this
level, and it's undesirable to have code that can only pretend to do that.
Any users of these functions cannot know what the state of the system is in
the error case. And the error paths are, to my knowledge, impossible to
test without adding custom error injection code.
Summary:
* This code has not worked reliably since its introduction.
* There is no evidence that it is used.
* It contains questionable rollback behaviors in error paths which are
difficult to test.
So let's remove it.
Fixes: ac71380071 ("powerpc/pseries: Add CPU dlpar remove functionality")
Fixes: 90edf184b9 ("powerpc/pseries: Add CPU dlpar add functionality")
Fixes: b015f6bc95 ("powerpc/pseries: Add cpu DLPAR support for drc-info property")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210927201933.76786-4-nathanl@linux.ibm.com
On pseries, cache nodes in the device tree can be added and removed by the
CPU DLPAR code as well as the partition migration (mobility) code. PowerVM
partitions in dedicated processor mode typically have L2 and L3 cache
nodes.
The CPU DLPAR code has the following shortcomings:
* Cache nodes returned as siblings of a new CPU node by
ibm,configure-connector are silently discarded; only the CPU node is
added to the device tree.
* Cache nodes which become unreferenced in the processor removal path are
not removed from the device tree. This can lead to duplicate nodes when
the post-migration device tree update code replaces cache nodes.
This is long-standing behavior. Presumably it has gone mostly unnoticed
because the two bugs have the property of obscuring each other in common
simple scenarios (e.g. remove a CPU and add it back). Likely you'd notice
only if you cared to inspect the device tree or the sysfs cacheinfo
information.
Booted with two processors:
$ pwd
/sys/firmware/devicetree/base/cpus
$ ls -1d */
l2-cache@2010/
l2-cache@2011/
l3-cache@3110/
l3-cache@3111/
PowerPC,POWER9@0/
PowerPC,POWER9@8/
$ lsprop */l2-cache
l2-cache@2010/l2-cache
00003110 (12560)
l2-cache@2011/l2-cache
00003111 (12561)
PowerPC,POWER9@0/l2-cache
00002010 (8208)
PowerPC,POWER9@8/l2-cache
00002011 (8209)
$ ls /sys/devices/system/cpu/cpu0/cache/
index0 index1 index2 index3
After DLPAR-adding PowerPC,POWER9@10, we see that its associated cache
nodes are absent, its threads' L2+L3 cacheinfo is unpopulated, and it is
missing a cache level in its sched domain hierarchy:
$ ls -1d */
l2-cache@2010/
l2-cache@2011/
l3-cache@3110/
l3-cache@3111/
PowerPC,POWER9@0/
PowerPC,POWER9@10/
PowerPC,POWER9@8/
$ lsprop PowerPC\,POWER9@10/l2-cache
PowerPC,POWER9@10/l2-cache
00002012 (8210)
$ ls /sys/devices/system/cpu/cpu16/cache/
index0 index1
$ grep . /sys/kernel/debug/sched/domains/cpu{0,8,16}/domain*/name
/sys/kernel/debug/sched/domains/cpu0/domain0/name:SMT
/sys/kernel/debug/sched/domains/cpu0/domain1/name:CACHE
/sys/kernel/debug/sched/domains/cpu0/domain2/name:DIE
/sys/kernel/debug/sched/domains/cpu8/domain0/name:SMT
/sys/kernel/debug/sched/domains/cpu8/domain1/name:CACHE
/sys/kernel/debug/sched/domains/cpu8/domain2/name:DIE
/sys/kernel/debug/sched/domains/cpu16/domain0/name:SMT
/sys/kernel/debug/sched/domains/cpu16/domain1/name:DIE
When removing PowerPC,POWER9@8, we see that its cache nodes are left
behind:
$ ls -1d */
l2-cache@2010/
l2-cache@2011/
l3-cache@3110/
l3-cache@3111/
PowerPC,POWER9@0/
When DLPAR is combined with VM migration, we can get duplicate nodes. E.g.
removing one processor, then migrating, adding a processor, and then
migrating again can result in warnings from the OF core during
post-migration device tree updates:
Duplicate name in cpus, renamed to "l2-cache@2011#1"
Duplicate name in cpus, renamed to "l3-cache@3111#1"
and nodes with duplicated phandles in the tree, making lookup behavior
unpredictable:
$ lsprop l[23]-cache@*/ibm,phandle
l2-cache@2010/ibm,phandle
00002010 (8208)
l2-cache@2011#1/ibm,phandle
00002011 (8209)
l2-cache@2011/ibm,phandle
00002011 (8209)
l3-cache@3110/ibm,phandle
00003110 (12560)
l3-cache@3111#1/ibm,phandle
00003111 (12561)
l3-cache@3111/ibm,phandle
00003111 (12561)
Address these issues by:
* Correctly processing siblings of the node returned from
dlpar_configure_connector().
* Removing cache nodes in the CPU remove path when it can be determined
that they are not associated with other CPUs or caches.
Use the of_changeset API in both cases, which allows us to keep the error
handling in this code from becoming more complex while ensuring that the
device tree cannot become inconsistent.
Fixes: ac71380071 ("powerpc/pseries: Add CPU dlpar remove functionality")
Fixes: 90edf184b9 ("powerpc/pseries: Add CPU dlpar add functionality")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210927201933.76786-2-nathanl@linux.ibm.com
On powerpc, pci_dev_is_added() is called as part of SR-IOV fixups
that are done under pcibios_add_device() which in turn is only called in
pci_device_add() whih is called when a PCI device is scanned.
pci_dev_assign_added() is called in pci_bus_add_device() which is only
called after scanning the device. Thus pci_dev_is_added() is always
false and can be dropped.
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Oliver O'Halloran <oohall@gmail.com>
[mpe: Tweak change log slightly to reflect Oliver's comments]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210910141940.2598035-2-schnelle@linux.ibm.com
