This reduces TLB misses by nearly 30x on a `git diff` workload on a
2-node POWER9 (59,800 -> 2,100) and reduces CPU cycles by 0.54%, due
to vfs hashes being allocated with 2MB pages.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210503091755.613393-1-npiggin@gmail.com
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Merge tag 'landlock_v34' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull Landlock LSM from James Morris:
"Add Landlock, a new LSM from Mickaël Salaün.
Briefly, Landlock provides for unprivileged application sandboxing.
From Mickaël's cover letter:
"The goal of Landlock is to enable to restrict ambient rights (e.g.
global filesystem access) for a set of processes. Because Landlock
is a stackable LSM [1], it makes possible to create safe security
sandboxes as new security layers in addition to the existing
system-wide access-controls. This kind of sandbox is expected to
help mitigate the security impact of bugs or unexpected/malicious
behaviors in user-space applications. Landlock empowers any
process, including unprivileged ones, to securely restrict
themselves.
Landlock is inspired by seccomp-bpf but instead of filtering
syscalls and their raw arguments, a Landlock rule can restrict the
use of kernel objects like file hierarchies, according to the
kernel semantic. Landlock also takes inspiration from other OS
sandbox mechanisms: XNU Sandbox, FreeBSD Capsicum or OpenBSD
Pledge/Unveil.
In this current form, Landlock misses some access-control features.
This enables to minimize this patch series and ease review. This
series still addresses multiple use cases, especially with the
combined use of seccomp-bpf: applications with built-in sandboxing,
init systems, security sandbox tools and security-oriented APIs [2]"
The cover letter and v34 posting is here:
https://lore.kernel.org/linux-security-module/20210422154123.13086-1-mic@digikod.net/
See also:
https://landlock.io/
This code has had extensive design discussion and review over several
years"
Link: https://lore.kernel.org/lkml/50db058a-7dde-441b-a7f9-f6837fe8b69f@schaufler-ca.com/ [1]
Link: https://lore.kernel.org/lkml/f646e1c7-33cf-333f-070c-0a40ad0468cd@digikod.net/ [2]
* tag 'landlock_v34' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
landlock: Enable user space to infer supported features
landlock: Add user and kernel documentation
samples/landlock: Add a sandbox manager example
selftests/landlock: Add user space tests
landlock: Add syscall implementations
arch: Wire up Landlock syscalls
fs,security: Add sb_delete hook
landlock: Support filesystem access-control
LSM: Infrastructure management of the superblock
landlock: Add ptrace restrictions
landlock: Set up the security framework and manage credentials
landlock: Add ruleset and domain management
landlock: Add object management
Merge misc updates from Andrew Morton:
"A few misc subsystems and some of MM.
175 patches.
Subsystems affected by this patch series: ia64, kbuild, scripts, sh,
ocfs2, kfifo, vfs, kernel/watchdog, and mm (slab-generic, slub,
kmemleak, debug, pagecache, msync, gup, memremap, memcg, pagemap,
mremap, dma, sparsemem, vmalloc, documentation, kasan, initialization,
pagealloc, and memory-failure)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (175 commits)
mm/memory-failure: unnecessary amount of unmapping
mm/mmzone.h: fix existing kernel-doc comments and link them to core-api
mm: page_alloc: ignore init_on_free=1 for debug_pagealloc=1
net: page_pool: use alloc_pages_bulk in refill code path
net: page_pool: refactor dma_map into own function page_pool_dma_map
SUNRPC: refresh rq_pages using a bulk page allocator
SUNRPC: set rq_page_end differently
mm/page_alloc: inline __rmqueue_pcplist
mm/page_alloc: optimize code layout for __alloc_pages_bulk
mm/page_alloc: add an array-based interface to the bulk page allocator
mm/page_alloc: add a bulk page allocator
mm/page_alloc: rename alloced to allocated
mm/page_alloc: duplicate include linux/vmalloc.h
mm, page_alloc: avoid page_to_pfn() in move_freepages()
mm/Kconfig: remove default DISCONTIGMEM_MANUAL
mm: page_alloc: dump migrate-failed pages
mm/mempolicy: fix mpol_misplaced kernel-doc
mm/mempolicy: rewrite alloc_pages_vma documentation
mm/mempolicy: rewrite alloc_pages documentation
mm/mempolicy: rename alloc_pages_current to alloc_pages
...
- Enable KFENCE for 32-bit.
- Implement EBPF for 32-bit.
- Convert 32-bit to do interrupt entry/exit in C.
- Convert 64-bit BookE to do interrupt entry/exit in C.
- Changes to our signal handling code to use user_access_begin/end() more extensively.
- Add support for time namespaces (CONFIG_TIME_NS)
- A series of fixes that allow us to reenable STRICT_KERNEL_RWX.
- Other smaller features, fixes & cleanups.
Thanks to: Alexey Kardashevskiy, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V,
Athira Rajeev, Bhaskar Chowdhury, Bixuan Cui, Cédric Le Goater, Chen Huang, Chris
Packham, Christophe Leroy, Christopher M. Riedl, Colin Ian King, Dan Carpenter, Daniel
Axtens, Daniel Henrique Barboza, David Gibson, Davidlohr Bueso, Denis Efremov,
dingsenjie, Dmitry Safonov, Dominic DeMarco, Fabiano Rosas, Ganesh Goudar, Geert
Uytterhoeven, Geetika Moolchandani, Greg Kurz, Guenter Roeck, Haren Myneni, He Ying,
Jiapeng Chong, Jordan Niethe, Laurent Dufour, Lee Jones, Leonardo Bras, Li Huafei,
Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Nathan Chancellor, Nathan
Lynch, Nicholas Piggin, Oliver O'Halloran, Paul Menzel, Pu Lehui, Randy Dunlap, Ravi
Bangoria, Rosen Penev, Russell Currey, Santosh Sivaraj, Sebastian Andrzej Siewior,
Segher Boessenkool, Shivaprasad G Bhat, Srikar Dronamraju, Stephen Rothwell, Thadeu Lima
de Souza Cascardo, Thomas Gleixner, Tony Ambardar, Tyrel Datwyler, Vaibhav Jain,
Vincenzo Frascino, Xiongwei Song, Yang Li, Yu Kuai, Zhang Yunkai.
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Merge tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
- Enable KFENCE for 32-bit.
- Implement EBPF for 32-bit.
- Convert 32-bit to do interrupt entry/exit in C.
- Convert 64-bit BookE to do interrupt entry/exit in C.
- Changes to our signal handling code to use user_access_begin/end()
more extensively.
- Add support for time namespaces (CONFIG_TIME_NS)
- A series of fixes that allow us to reenable STRICT_KERNEL_RWX.
- Other smaller features, fixes & cleanups.
Thanks to Alexey Kardashevskiy, Andreas Schwab, Andrew Donnellan, Aneesh
Kumar K.V, Athira Rajeev, Bhaskar Chowdhury, Bixuan Cui, Cédric Le
Goater, Chen Huang, Chris Packham, Christophe Leroy, Christopher M.
Riedl, Colin Ian King, Dan Carpenter, Daniel Axtens, Daniel Henrique
Barboza, David Gibson, Davidlohr Bueso, Denis Efremov, dingsenjie,
Dmitry Safonov, Dominic DeMarco, Fabiano Rosas, Ganesh Goudar, Geert
Uytterhoeven, Geetika Moolchandani, Greg Kurz, Guenter Roeck, Haren
Myneni, He Ying, Jiapeng Chong, Jordan Niethe, Laurent Dufour, Lee
Jones, Leonardo Bras, Li Huafei, Madhavan Srinivasan, Mahesh Salgaonkar,
Masahiro Yamada, Nathan Chancellor, Nathan Lynch, Nicholas Piggin,
Oliver O'Halloran, Paul Menzel, Pu Lehui, Randy Dunlap, Ravi Bangoria,
Rosen Penev, Russell Currey, Santosh Sivaraj, Sebastian Andrzej Siewior,
Segher Boessenkool, Shivaprasad G Bhat, Srikar Dronamraju, Stephen
Rothwell, Thadeu Lima de Souza Cascardo, Thomas Gleixner, Tony Ambardar,
Tyrel Datwyler, Vaibhav Jain, Vincenzo Frascino, Xiongwei Song, Yang Li,
Yu Kuai, and Zhang Yunkai.
* tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (302 commits)
powerpc/signal32: Fix erroneous SIGSEGV on RT signal return
powerpc: Avoid clang uninitialized warning in __get_user_size_allowed
powerpc/papr_scm: Mark nvdimm as unarmed if needed during probe
powerpc/kvm: Fix build error when PPC_MEM_KEYS/PPC_PSERIES=n
powerpc/kasan: Fix shadow start address with modules
powerpc/kernel/iommu: Use largepool as a last resort when !largealloc
powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs
powerpc/44x: fix spelling mistake in Kconfig "varients" -> "variants"
powerpc/iommu: Annotate nested lock for lockdep
powerpc/iommu: Do not immediately panic when failed IOMMU table allocation
powerpc/iommu: Allocate it_map by vmalloc
selftests/powerpc: remove unneeded semicolon
powerpc/64s: remove unneeded semicolon
powerpc/eeh: remove unneeded semicolon
powerpc/selftests: Add selftest to test concurrent perf/ptrace events
powerpc/selftests/perf-hwbreak: Add testcases for 2nd DAWR
powerpc/selftests/perf-hwbreak: Coalesce event creation code
powerpc/selftests/ptrace-hwbreak: Add testcases for 2nd DAWR
powerpc/configs: Add IBMVNIC to some 64-bit configs
selftests/powerpc: Add uaccess flush test
...
This is a shim around vunmap_range, get rid of it.
Move the main API comment from the _noflush variant to the normal
variant, and make _noflush internal to mm/.
[npiggin@gmail.com: fix nommu builds and a comment bug per sfr]
Link: https://lkml.kernel.org/r/1617292598.m6g0knx24s.astroid@bobo.none
[akpm@linux-foundation.org: move vunmap_range_noflush() stub inside !CONFIG_MMU, not !CONFIG_NUMA]
[npiggin@gmail.com: fix nommu builds]
Link: https://lkml.kernel.org/r/1617292497.o1uhq5ipxp.astroid@bobo.none
Link: https://lkml.kernel.org/r/20210322021806.892164-5-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Cédric Le Goater <clg@kaod.org>
Cc: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'for_v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull quota, ext2, reiserfs updates from Jan Kara:
- support for path (instead of device) based quotactl syscall
(quotactl_path(2))
- ext2 conversion to kmap_local()
- other minor cleanups & fixes
* tag 'for_v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fs/reiserfs/journal.c: delete useless variables
fs/ext2: Replace kmap() with kmap_local_page()
ext2: Match up ext2_put_page() with ext2_dotdot() and ext2_find_entry()
fs/ext2/: fix misspellings using codespell tool
quota: report warning limits for realtime space quotas
quota: wire up quotactl_path
quota: Add mountpath based quota support
Return of user_read_access_begin() is tested the wrong way,
leading to a SIGSEGV when the user address is valid and likely
an Oops when the user address is bad.
Fix the test.
Fixes: 887f3ceb51 ("powerpc/signal32: Convert do_setcontext[_tm]() to user access block")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a29aadc54c93bcbf069a83615fa102ca0f59c3ae.1619185912.git.christophe.leroy@csgroup.eu
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Merge tag 'printk-for-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- Stop synchronizing kernel log buffer readers by logbuf_lock. As a
result, the access to the buffer is fully lockless now.
Note that printk() itself still uses locks because it tries to flush
the messages to the console immediately. Also the per-CPU temporary
buffers are still there because they prevent infinite recursion and
serialize backtraces from NMI. All this is going to change in the
future.
- kmsg_dump API rework and cleanup as a side effect of the logbuf_lock
removal.
- Make bstr_printf() aware that %pf and %pF formats could deference the
given pointer.
- Show also page flags by %pGp format.
- Clarify the documentation for plain pointer printing.
- Do not show no_hash_pointers warning multiple times.
- Update Senozhatsky email address.
- Some clean up.
* tag 'printk-for-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: (24 commits)
lib/vsprintf.c: remove leftover 'f' and 'F' cases from bstr_printf()
printk: clarify the documentation for plain pointer printing
kernel/printk.c: Fixed mundane typos
printk: rename vprintk_func to vprintk
vsprintf: dump full information of page flags in pGp
mm, slub: don't combine pr_err with INFO
mm, slub: use pGp to print page flags
MAINTAINERS: update Senozhatsky email address
lib/vsprintf: do not show no_hash_pointers message multiple times
printk: console: remove unnecessary safe buffer usage
printk: kmsg_dump: remove _nolock() variants
printk: remove logbuf_lock
printk: introduce a kmsg_dump iterator
printk: kmsg_dumper: remove @active field
printk: add syslog_lock
printk: use atomic64_t for devkmsg_user.seq
printk: use seqcount_latch for clear_seq
printk: introduce CONSOLE_LOG_MAX
printk: consolidate kmsg_dump_get_buffer/syslog_print_all code
printk: refactor kmsg_dump_get_buffer()
...
As of today, doing iommu_range_alloc() only for !largealloc (npages <= 15)
will only be able to use 3/4 of the available pages, given pages on
largepool not being available for !largealloc.
This could mean some drivers not being able to fully use all the available
pages for the DMA window.
Add pages on largepool as a last resort for !largealloc, making all pages
of the DMA window available.
Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210318174414.684630-2-leobras.c@gmail.com
Currently both iommu_alloc_coherent() and iommu_free_coherent() align the
desired allocation size to PAGE_SIZE, and gets system pages and IOMMU
mappings (TCEs) for that value.
When IOMMU_PAGE_SIZE < PAGE_SIZE, this behavior may cause unnecessary
TCEs to be created for mapping the whole system page.
Example:
- PAGE_SIZE = 64k, IOMMU_PAGE_SIZE() = 4k
- iommu_alloc_coherent() is called for 128 bytes
- 1 system page (64k) is allocated
- 16 IOMMU pages (16 x 4k) are allocated (16 TCEs used)
It would be enough to use a single TCE for this, so 15 TCEs are
wasted in the process.
Update iommu_*_coherent() to make sure the size alignment happens only
for IOMMU_PAGE_SIZE() before calling iommu_alloc() and iommu_free().
Also, on iommu_range_alloc(), replace ALIGN(n, 1 << tbl->it_page_shift)
with IOMMU_PAGE_ALIGN(n, tbl), which is easier to read and does the
same.
Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210318174414.684630-1-leobras.c@gmail.com
The IOMMU table is divided into pools for concurrent mappings and each
pool has a separate spinlock. When taking the ownership of an IOMMU group
to pass through a device to a VM, we lock these spinlocks which triggers
a false negative warning in lockdep (below).
This fixes it by annotating the large pool's spinlock as a nest lock
which makes lockdep not complaining when locking nested locks if
the nest lock is locked already.
===
WARNING: possible recursive locking detected
5.11.0-le_syzkaller_a+fstn1 #100 Not tainted
--------------------------------------------
qemu-system-ppc/4129 is trying to acquire lock:
c0000000119bddb0 (&(p->lock)/1){....}-{2:2}, at: iommu_take_ownership+0xac/0x1e0
but task is already holding lock:
c0000000119bdd30 (&(p->lock)/1){....}-{2:2}, at: iommu_take_ownership+0xac/0x1e0
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&(p->lock)/1);
lock(&(p->lock)/1);
===
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210301063653.51003-1-aik@ozlabs.ru
Most platforms allocate IOMMU table structures (specifically it_map)
at the boot time and when this fails - it is a valid reason for panic().
However the powernv platform allocates it_map after a device is returned
to the host OS after being passed through and this happens long after
the host OS booted. It is quite possible to trigger the it_map allocation
panic() and kill the host even though it is not necessary - the host OS
can still use the DMA bypass mode (requires a tiny fraction of it_map's
memory) and even if that fails, the host OS is runnnable as it was without
the device for which allocating it_map causes the panic.
Instead of immediately crashing in a powernv/ioda2 system, this prints
an error and continues. All other platforms still call panic().
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Leonardo Bras <leobras.c@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210216033307.69863-3-aik@ozlabs.ru
The IOMMU table uses the it_map bitmap to keep track of allocated DMA
pages. This has always been a contiguous array allocated at either
the boot time or when a passed through device is returned to the host OS.
The it_map memory is allocated by alloc_pages() which allocates
contiguous physical memory.
Such allocation method occasionally creates a problem when there is
no big chunk of memory available (no free memory or too fragmented).
On powernv/ioda2 the default DMA window requires 16MB for it_map.
This replaces alloc_pages_node() with vzalloc_node() which allocates
contiguous block but in virtual memory. This should reduce changes of
failure but should not cause other behavioral changes as it_map is only
used by the kernel's DMA hooks/api when MMU is on.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210216033307.69863-2-aik@ozlabs.ru
Eliminate the following coccicheck warning:
./arch/powerpc/kernel/eeh.c:782:2-3: Unneeded semicolon
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reviewed-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1612236096-91154-1-git-send-email-yang.lee@linux.alibaba.com
[ 0.000000] ioremap() called early from find_legacy_serial_ports+0x3cc/0x474. Use early_ioremap() instead
find_legacy_serial_ports() is called early from setup_arch(), before
paging_init(). vmalloc is not available yet, ioremap shouldn't be
used that early.
Use early_ioremap() and switch to a regular ioremap() later.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/103ed8ee9e5973c958ec1da2d0b0764f69395d01.1618925560.git.christophe.leroy@csgroup.eu
Sparse says:
arch/powerpc/kernel/fadump.c:48:16: warning: symbol 'fadump_kobj' was not declared. Should it be static?
arch/powerpc/kernel/fadump.c:55:27: warning: symbol 'crash_mrange_info' was not declared. Should it be static?
arch/powerpc/kernel/fadump.c:61:27: warning: symbol 'reserved_mrange_info' was not declared. Should it be static?
arch/powerpc/kernel/fadump.c:83:12: warning: symbol 'fadump_cma_init' was not declared. Should it be static?
And indeed none of them are used outside this file, they can all be made
static. Also fadump_kobj needs to be moved inside the ifdef where it's
used.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210421125402.1955013-1-mpe@ellerman.id.au
When probe_kernel_read_inst() was created, it was to mimic
probe_kernel_read() function.
Since then, probe_kernel_read() has been renamed
copy_from_kernel_nofault().
Rename probe_kernel_read_inst() into copy_inst_from_kernel_nofault().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b783d1f7cdb8914992384a669a2af57051b6bdcf.1618405715.git.christophe.leroy@csgroup.eu
When we hit an UE while using machine check safe copy routines,
ignore_event flag is set and the event is ignored by mce handler,
And the flag is also saved for defered handling and printing of
mce event information, But as of now saving of this flag is done
on checking if the effective address is provided or physical address
is calculated, which is not right.
Save ignore_event flag regardless of whether the effective address is
provided or physical address is calculated.
Without this change following log is seen, when the event is to be
ignored.
[ 512.971365] MCE: CPU1: machine check (Severe) UE Load/Store [Recovered]
[ 512.971509] MCE: CPU1: NIP: [c0000000000b67c0] memcpy+0x40/0x90
[ 512.971655] MCE: CPU1: Initiator CPU
[ 512.971739] MCE: CPU1: Unknown
[ 512.972209] MCE: CPU1: machine check (Severe) UE Load/Store [Recovered]
[ 512.972334] MCE: CPU1: NIP: [c0000000000b6808] memcpy+0x88/0x90
[ 512.972456] MCE: CPU1: Initiator CPU
[ 512.972534] MCE: CPU1: Unknown
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Reviewed-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210407045816.352276-1-ganeshgr@linux.ibm.com
For that, create a 32 bits version of patch_imm64_load_insns()
and create a patch_imm_load_insns() which calls
patch_imm32_load_insns() on PPC32 and patch_imm64_load_insns()
on PPC64.
Adapt optprobes_head.S for PPC32. Use PPC_LL/PPC_STL macros instead
of raw ld/std, opt out things linked to paca and use stmw/lmw to
save/restore registers.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/bad58c66859b2a475c0ad516b53164ae3b4853cd.1618927318.git.christophe.leroy@csgroup.eu
sfr reports that the allyesconfig build fails with:
arch/powerpc/kernel/fadump.c: In function 'crash_fadump':
arch/powerpc/kernel/fadump.c:731:28: error: 'INTERRUPT_SYSTEM_RESET' undeclared
731 | if (TRAP(&(fdh->regs)) == INTERRUPT_SYSTEM_RESET) {
Add an include of interrupt.h to fix it.
Fixes: 7153d4bf0b ("powerpc/traps: Enhance readability for trap types")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
[mpe: Reformat change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210419191425.281dc58a@canb.auug.org.au
Starting with ISA v3.1, LPCR[AIL] no longer controls the interrupt
mode for HV=1 interrupts. Instead, a new LPCR[HAIL] bit is defined
which behaves like AIL=3 for HV interrupts when set.
Set HAIL on bare metal to give us mmu-on interrupts and improve
performance.
This also fixes an scv bug: we don't implement scv real mode (AIL=0)
vectors because they are at an inconvenient location, so we just
disable scv support when AIL can not be set. However powernv assumes
that LPCR[AIL] will enable AIL mode so it enables scv support despite
HV interrupts being AIL=0, which causes scv interrupts to go off into
the weeds.
Fixes: 7fa95f9ada ("powerpc/64s: system call support for scv/rfscv instructions")
Cc: stable@vger.kernel.org # v5.9+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210402024124.545826-1-npiggin@gmail.com
Define macros to list ppc interrupt types in interttupt.h, replace the
reference of the trap hex values with these macros.
Referred the hex numbers in arch/powerpc/kernel/exceptions-64e.S,
arch/powerpc/kernel/exceptions-64s.S, arch/powerpc/kernel/head_*.S,
arch/powerpc/kernel/head_booke.h and arch/powerpc/include/asm/kvm_asm.h.
Signed-off-by: Xiongwei Song <sxwjean@gmail.com>
[mpe: Resolve conflicts in nmi_disables_ftrace(), fix 40x build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1618398033-13025-1-git-send-email-sxwjean@me.com
On systems with large CPUs per node, even with the filtered matching of
related CPUs, there can be large number of calls to cpu_to_chip_id for
the same CPU. For example with 4096 vCPU, 1 node QEMU configuration,
with 4 threads per core, system could be see upto 1024 calls to
cpu_to_chip_id() for the same CPU. On a given system, cpu_to_chip_id()
for a given CPU would always return the same. Hence cache the result in
a lookup table for use in subsequent calls.
Since all CPUs sharing the same core will belong to the same chip, the
lookup_table has an entry for one CPU per core. chip_id_lookup_table is
not being freed and would be used on subsequent CPU online post CPU
offline.
Reported-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210415120934.232271-4-srikar@linux.vnet.ibm.com
Daniel reported that with Commit 4ca234a9cb ("powerpc/smp: Stop
updating cpu_core_mask") QEMU was unable to set single NUMA node SMP
topologies such as:
-smp 8,maxcpus=8,cores=2,threads=2,sockets=2
i.e he expected 2 sockets in one NUMA node.
The above commit helped to reduce boot time on Large Systems for
example 4096 vCPU single socket QEMU instance. PAPR is silent on
having more than one socket within a NUMA node.
cpu_core_mask and cpu_cpu_mask for any CPU would be same unless the
number of sockets is different from the number of NUMA nodes.
One option is to reintroduce cpu_core_mask but use a slightly
different method to arrive at the cpu_core_mask. Previously each CPU's
chip-id would be compared with all other CPU's chip-id to verify if
both the CPUs were related at the chip level. Now if a CPU 'A' is
found related / (unrelated) to another CPU 'B', all the thread
siblings of 'A' and thread siblings of 'B' are automatically marked as
related / (unrelated).
Also if a platform doesn't support ibm,chip-id property, i.e its
cpu_to_chip_id returns -1, cpu_core_map holds a copy of
cpu_cpu_mask().
Fixes: 4ca234a9cb ("powerpc/smp: Stop updating cpu_core_mask")
Reported-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210415120934.232271-2-srikar@linux.vnet.ibm.com
This patch adds the necessary glue to provide time namespaces.
Things are mainly copied from ARM64.
__arch_get_timens_vdso_data() calculates timens vdso data position
based on the vdso data position, knowing it is the next page in vvar.
This avoids having to redo the mflr/bcl/mflr/mtlr dance to locate
the page relative to running code position.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> # vDSO parts
Acked-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1a15495f80ec19a87b16cf874dbf7c3fa5ec40fe.1617209142.git.christophe.leroy@csgroup.eu
Since commit 511157ab64 ("powerpc/vdso: Move vdso datapage up front")
VVAR page is in front of the VDSO area. In result it breaks CRIU
(Checkpoint Restore In Userspace) [1], where CRIU expects that "[vdso]"
from /proc/../maps points at ELF/vdso image, rather than at VVAR data page.
Laurent made a patch to keep CRIU working (by reading aux vector).
But I think it still makes sence to separate two mappings into different
VMAs. It will also make ppc64 less "special" for userspace and as
a side-bonus will make VVAR page un-writable by debugger (which previously
would COW page and can be unexpected).
I opportunistically Cc stable on it: I understand that usually such
stuff isn't a stable material, but that will allow us in CRIU have
one workaround less that is needed just for one release (v5.11) on
one platform (ppc64), which we otherwise have to maintain.
I wouldn't go as far as to say that the commit 511157ab64 is ABI
regression as no other userspace got broken, but I'd really appreciate
if it gets backported to v5.11 after v5.12 is released, so as not
to complicate already non-simple CRIU-vdso code. Thanks!
[1]: https://github.com/checkpoint-restore/criu/issues/1417
Cc: stable@vger.kernel.org # v5.11
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> # vDSO parts.
Acked-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f401eb1ebc0bfc4d8f0e10dc8e525fd409eb68e2.1617209142.git.christophe.leroy@csgroup.eu
All subarchitectures always save all GPRs to pt_regs interrupt frames
now. Remove FULL_REGS and associated bits.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210316104206.407354-11-npiggin@gmail.com
With non-volatile registers saved on interrupt, bad_page_fault
can now be called by do_page_fault.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210316104206.407354-9-npiggin@gmail.com
With the new interrupt exit code, context tracking can be managed
more precisely, so remove the last of the 64e workarounds and switch
to the new context tracking code already used by 64s.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210316104206.407354-8-npiggin@gmail.com
64e non-maskable interrupts save the state of the irq soft-mask in
asm. This can be done in C in interrupt wrappers as 64s does.
I haven't been able to test this with qemu because it doesn't seem
to cause FSL bookE WDT interrupts.
This makes WatchdogException an NMI interrupt, which affects 32-bit
as well (okay, or create a new handler?)
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210316104206.407354-6-npiggin@gmail.com
Update the new C and asm interrupt return code to account for 64e
specifics, switch over to use it.
The now-unused old ret_from_except code, that was moved to 64e after the
64s conversion, is removed.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210316104206.407354-5-npiggin@gmail.com
This makes adjustments to 64-bit asm and common C interrupt return
code to be usable by the 64e subarchitecture.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210316104206.407354-4-npiggin@gmail.com
user_exit_irqoff() -> __context_tracking_exit -> vtime_user_exit
warns in __seqprop_assert due to lockdep thinking preemption is enabled
because trace_hardirqs_off() has not yet been called.
Switch the order of these two calls, which matches their ordering in
interrupt_enter_prepare.
Fixes: 5f0b6ac390 ("powerpc/64/syscall: Reconcile interrupts")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210316104206.407354-2-npiggin@gmail.com
Many architectures duplicate similar shell scripts.
This commit converts powerpc to use scripts/syscallhdr.sh.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210301153019.362742-2-masahiroy@kernel.org
Many architectures duplicate similar shell scripts.
This commit converts powerpc to use scripts/syscalltbl.sh. This also
unifies syscall_table_32.h and syscall_table_c32.h.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210301153019.362742-1-masahiroy@kernel.org
RTAS_RMOBUF_MAX doesn't actually describe a "maximum" value in any
sense. It represents the size of an area of memory set aside for user
space to use as work areas for certain RTAS calls.
Rename it to RTAS_USER_REGION_SIZE.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210408140630.205502-6-nathanl@linux.ibm.com
Reduce conditionally compiled sections within rtas_initialize() by
moving the filter table initialization into its own function already
guarded by CONFIG_PPC_RTAS_FILTER. No behavior change intended.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210408140630.205502-5-nathanl@linux.ibm.com
There's not a compelling reason to cache the value of the token for
the ibm,suspend-me function. Just look it up when needed in the RTAS
syscall's special case for it.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210408140630.205502-4-nathanl@linux.ibm.com
Add kerneldoc for ppc_rtas_rmo_buf_show(), the callback for
/proc/powerpc/rtas/rmo_buffer, explaining its expected use.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210408140630.205502-2-nathanl@linux.ibm.com
During the EEH MMIO error checking, the current implementation fails to map
the (virtual) MMIO address back to the pci device on radix with hugepage
mappings for I/O. This results into failure to dispatch EEH event with no
recovery even when EEH capability has been enabled on the device.
eeh_check_failure(token) # token = virtual MMIO address
addr = eeh_token_to_phys(token);
edev = eeh_addr_cache_get_dev(addr);
if (!edev)
return 0;
eeh_dev_check_failure(edev); <= Dispatch the EEH event
In case of hugepage mappings, eeh_token_to_phys() has a bug in virt -> phys
translation that results in wrong physical address, which is then passed to
eeh_addr_cache_get_dev() to match it against cached pci I/O address ranges
to get to a PCI device. Hence, it fails to find a match and the EEH event
never gets dispatched leaving the device in failed state.
The commit 3343962068 ("powerpc/eeh: Handle hugepages in ioremap space")
introduced following logic to translate virt to phys for hugepage mappings:
eeh_token_to_phys():
+ pa = pte_pfn(*ptep);
+
+ /* On radix we can do hugepage mappings for io, so handle that */
+ if (hugepage_shift) {
+ pa <<= hugepage_shift; <= This is wrong
+ pa |= token & ((1ul << hugepage_shift) - 1);
+ }
This patch fixes the virt -> phys translation in eeh_token_to_phys()
function.
$ cat /sys/kernel/debug/powerpc/eeh_address_cache
mem addr range [0x0000040080000000-0x00000400807fffff]: 0030:01:00.1
mem addr range [0x0000040080800000-0x0000040080ffffff]: 0030:01:00.1
mem addr range [0x0000040081000000-0x00000400817fffff]: 0030:01:00.0
mem addr range [0x0000040081800000-0x0000040081ffffff]: 0030:01:00.0
mem addr range [0x0000040082000000-0x000004008207ffff]: 0030:01:00.1
mem addr range [0x0000040082080000-0x00000400820fffff]: 0030:01:00.0
mem addr range [0x0000040082100000-0x000004008210ffff]: 0030:01:00.1
mem addr range [0x0000040082110000-0x000004008211ffff]: 0030:01:00.0
Above is the list of cached io address ranges of pci 0030:01:00.<fn>.
Before this patch:
Tracing 'arg1' of function eeh_addr_cache_get_dev() during error injection
clearly shows that 'addr=' contains wrong physical address:
kworker/u16:0-7 [001] .... 108.883775: eeh_addr_cache_get_dev:
(eeh_addr_cache_get_dev+0xc/0xf0) addr=0x80103000a510
dmesg shows no EEH recovery messages:
[ 108.563768] bnx2x: [bnx2x_timer:5801(eth2)]MFW seems hanged: drv_pulse (0x9ae) != mcp_pulse (0x7fff)
[ 108.563788] bnx2x: [bnx2x_hw_stats_update:870(eth2)]NIG timer max (4294967295)
[ 108.883788] bnx2x: [bnx2x_acquire_hw_lock:2013(eth1)]lock_status 0xffffffff resource_bit 0x1
[ 108.884407] bnx2x 0030:01:00.0 eth1: MDC/MDIO access timeout
[ 108.884976] bnx2x 0030:01:00.0 eth1: MDC/MDIO access timeout
<..>
After this patch:
eeh_addr_cache_get_dev() trace shows correct physical address:
<idle>-0 [001] ..s. 1043.123828: eeh_addr_cache_get_dev:
(eeh_addr_cache_get_dev+0xc/0xf0) addr=0x40080bc7cd8
dmesg logs shows EEH recovery getting triggerred:
[ 964.323980] bnx2x: [bnx2x_timer:5801(eth2)]MFW seems hanged: drv_pulse (0x746f) != mcp_pulse (0x7fff)
[ 964.323991] EEH: Recovering PHB#30-PE#10000
[ 964.324002] EEH: PE location: N/A, PHB location: N/A
[ 964.324006] EEH: Frozen PHB#30-PE#10000 detected
<..>
Fixes: 3343962068 ("powerpc/eeh: Handle hugepages in ioremap space")
Cc: stable@vger.kernel.org # v5.3+
Reported-by: Dominic DeMarco <ddemarc@us.ibm.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/161821396263.48361.2796709239866588652.stgit@jupiter
Nicholas Piggin