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This is the 4.19.8 stable release
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commit fe60522ec60082a1dd735691b82c64f65d4ad15e upstream.
The function_graph_enter() function does the work of calling the function
graph hook function and the management of the shadow stack, simplifying the
work done in the architecture dependent prepare_ftrace_return().
Have powerpc use the new code, and remove the shadow stack management as well as
having to set up the trace structure.
This is needed to prepare for a fix of a design bug on how the curr_ret_stack
is used.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: stable@kernel.org
Fixes: 03274a3ffb449 ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 437ccdc8ce629470babdda1a7086e2f477048cbd ]
When VPHN function is not supported and during cpu hotplug event,
kernel prints message 'VPHN function not supported. Disabling
polling...'. Currently it prints on every hotplug event, it floods
dmesg when a KVM guest tries to hotplug huge number of vcpus, let's
just print once and suppress further kernel prints.
Signed-off-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 43c6494fa1499912c8177e71450c0279041152a6 ]
Back in 2006 Ben added some workarounds for a misbehaviour in the
Spider IO bridge used on early Cell machines, see commit
014da7ff47b5 ("[POWERPC] Cell "Spider" MMIO workarounds"). Later these
were made to be generic, ie. not tied specifically to Spider.
The code stashes a token in the high bits (59-48) of virtual addresses
used for IO (eg. returned from ioremap()). This works fine when using
the Hash MMU, but when we're using the Radix MMU the bits used for the
token overlap with some of the bits of the virtual address.
This is because the maximum virtual address is larger with Radix, up
to c00fffffffffffff, and in fact we use that high part of the address
range for ioremap(), see RADIX_KERN_IO_START.
As it happens the bits that are used overlap with the bits that
differentiate an IO address vs a linear map address. If the resulting
address lies outside the linear mapping we will crash (see below), if
not we just corrupt memory.
virtio-pci 0000:00:00.0: Using 64-bit direct DMA at offset 800000000000000
Unable to handle kernel paging request for data at address 0xc000000080000014
...
CFAR: c000000000626b98 DAR: c000000080000014 DSISR: 42000000 IRQMASK: 0
GPR00: c0000000006c54fc c00000003e523378 c0000000016de600 0000000000000000
GPR04: c00c000080000014 0000000000000007 0fffffff000affff 0000000000000030
^^^^
...
NIP [c000000000626c5c] .iowrite8+0xec/0x100
LR [c0000000006c992c] .vp_reset+0x2c/0x90
Call Trace:
.pci_bus_read_config_dword+0xc4/0x120 (unreliable)
.register_virtio_device+0x13c/0x1c0
.virtio_pci_probe+0x148/0x1f0
.local_pci_probe+0x68/0x140
.pci_device_probe+0x164/0x220
.really_probe+0x274/0x3b0
.driver_probe_device+0x80/0x170
.__driver_attach+0x14c/0x150
.bus_for_each_dev+0xb8/0x130
.driver_attach+0x34/0x50
.bus_add_driver+0x178/0x2f0
.driver_register+0x90/0x1a0
.__pci_register_driver+0x6c/0x90
.virtio_pci_driver_init+0x2c/0x40
.do_one_initcall+0x64/0x280
.kernel_init_freeable+0x36c/0x474
.kernel_init+0x24/0x160
.ret_from_kernel_thread+0x58/0x7c
This hasn't been a problem because CONFIG_PPC_IO_WORKAROUNDS which
enables this code is usually not enabled. It is only enabled when it's
selected by PPC_CELL_NATIVE which is only selected by
PPC_IBM_CELL_BLADE and that in turn depends on BIG_ENDIAN. So in order
to hit the bug you need to build a big endian kernel, with IBM Cell
Blade support enabled, as well as Radix MMU support, and then boot
that on Power9 using Radix MMU.
Still we can fix the bug, so let's do that. We simply use fewer bits
for the token, taking the union of the restrictions on the address
from both Hash and Radix, we end up with 8 bits we can use for the
token. The only user of the token is iowa_mem_find_bus() which only
supports 8 token values, so 8 bits is plenty for that.
Fixes: 566ca99af026 ("powerpc/mm/radix: Add dummy radix_enabled()")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 28c5bcf74fa07c25d5bd118d1271920f51ce2a98 ]
TRACE_INCLUDE_PATH and TRACE_INCLUDE_FILE are used by
<trace/define_trace.h>, so like that #include, they should
be outside #ifdef protection.
They also need to be #undefed before defining, in case multiple trace
headers are included by the same C file. This became the case on
book3e after commit cf4a6085151a ("powerpc/mm: Add missing tracepoint for
tlbie"), leading to the following build error:
CC arch/powerpc/kvm/powerpc.o
In file included from arch/powerpc/kvm/powerpc.c:51:0:
arch/powerpc/kvm/trace.h:9:0: error: "TRACE_INCLUDE_PATH" redefined
[-Werror]
#define TRACE_INCLUDE_PATH .
^
In file included from arch/powerpc/kvm/../mm/mmu_decl.h:25:0,
from arch/powerpc/kvm/powerpc.c:48:
./arch/powerpc/include/asm/trace.h:224:0: note: this is the location of
the previous definition
#define TRACE_INCLUDE_PATH asm
^
cc1: all warnings being treated as errors
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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This is the 4.19.5 stable release
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commit cc4ebf5c0a3440ed0a32d25c55ebdb6ce5f3c0bc upstream.
This reverts commit 4f94b2c7462d9720b2afa7e8e8d4c19446bb31ce.
That commit was buggy, as it used rlwinm instead of rlwimi.
Instead of fixing that bug, we revert the previous commit in order to
reduce the dependency between L1 entries and L2 entries
Fixes: 4f94b2c7462d9 ("powerpc/8xx: Use L1 entry APG to handle _PAGE_ACCESSED for CONFIG_SWAP")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 3f7daf3d7582dc6628ac40a9045dd1bbd80c5f35 ]
When hot-removing memory release_mem_region_adjustable() splits iomem
resources if they are not the exact size of the memory being
hot-deleted. Adding this memory back to the kernel adds a new resource.
Eg a node has memory 0x0 - 0xfffffffff. Hot-removing 1GB from
0xf40000000 results in the single resource 0x0-0xfffffffff being split
into two resources: 0x0-0xf3fffffff and 0xf80000000-0xfffffffff.
When we hot-add the memory back we now have three resources:
0x0-0xf3fffffff, 0xf40000000-0xf7fffffff, and 0xf80000000-0xfffffffff.
This is an issue if we try to remove some memory that overlaps
resources. Eg when trying to remove 2GB at address 0xf40000000,
release_mem_region_adjustable() fails as it expects the chunk of memory
to be within the boundaries of a single resource. We then get the
warning: "Unable to release resource" and attempting to use memtrace
again gives us this error: "bash: echo: write error: Resource
temporarily unavailable"
This patch makes memtrace remove memory in chunks that are always the
same size from an address that is always equal to end_of_memory -
n*size, for some n. So hotremoving and hotadding memory of different
sizes will now not attempt to remove memory that spans multiple
resources.
Signed-off-by: Rashmica Gupta <rashmica.g@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit ee9d21b3b3583712029a0db65a4b7c081d08d3b3 ]
When building with clang crt0's _zimage_start is not marked weak, which
breaks the build when linking the kernel image:
$ objdump -t arch/powerpc/boot/crt0.o |grep _zimage_start$
0000000000000058 g .text 0000000000000000 _zimage_start
ld: arch/powerpc/boot/wrapper.a(crt0.o): in function '_zimage_start':
(.text+0x58): multiple definition of '_zimage_start';
arch/powerpc/boot/pseries-head.o:(.text+0x0): first defined here
Clang requires the .weak directive to appear after the symbol is
declared. The binutils manual says:
This directive sets the weak attribute on the comma separated list of
symbol names. If the symbols do not already exist, they will be
created.
So it appears this is different with clang. The only reference I could
see for this was an OpenBSD mailing list post[1].
Changing it to be after the declaration fixes building with Clang, and
still works with GCC.
$ objdump -t arch/powerpc/boot/crt0.o |grep _zimage_start$
0000000000000058 w .text 0000000000000000 _zimage_start
Reported to clang as https://bugs.llvm.org/show_bug.cgi?id=38921
[1] https://groups.google.com/forum/#!topic/fa.openbsd.tech/PAgKKen2YCY
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 803d690e68f0c5230183f1a42c7d50a41d16e380 ]
When a process allocates a hugepage, the following leak is
reported by kmemleak. This is a false positive which is
due to the pointer to the table being stored in the PGD
as physical memory address and not virtual memory pointer.
unreferenced object 0xc30f8200 (size 512):
comm "mmap", pid 374, jiffies 4872494 (age 627.630s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<e32b68da>] huge_pte_alloc+0xdc/0x1f8
[<9e0df1e1>] hugetlb_fault+0x560/0x8f8
[<7938ec6c>] follow_hugetlb_page+0x14c/0x44c
[<afbdb405>] __get_user_pages+0x1c4/0x3dc
[<b8fd7cd9>] __mm_populate+0xac/0x140
[<3215421e>] vm_mmap_pgoff+0xb4/0xb8
[<c148db69>] ksys_mmap_pgoff+0xcc/0x1fc
[<4fcd760f>] ret_from_syscall+0x0/0x38
See commit a984506c542e2 ("powerpc/mm: Don't report PUDs as
memory leaks when using kmemleak") for detailed explanation.
To fix that, this patch tells kmemleak to ignore the allocated
hugepage table.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit f5e284803a7206d43e26f9ffcae5de9626d95e37 ]
When enumerating page size definitions to check hardware support,
we construct a constant which is (1U << (def->shift - 10)).
However, the array of page size definitions is only initalised for
various MMU_PAGE_* constants, so it contains a number of 0-initialised
elements with def->shift == 0. This means we end up shifting by a
very large number, which gives the following UBSan splat:
================================================================================
UBSAN: Undefined behaviour in /home/dja/dev/linux/linux/arch/powerpc/mm/tlb_nohash.c:506:21
shift exponent 4294967286 is too large for 32-bit type 'unsigned int'
CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-rc3-00045-ga604f927b012-dirty #6
Call Trace:
[c00000000101bc20] [c000000000a13d54] .dump_stack+0xa8/0xec (unreliable)
[c00000000101bcb0] [c0000000004f20a8] .ubsan_epilogue+0x18/0x64
[c00000000101bd30] [c0000000004f2b10] .__ubsan_handle_shift_out_of_bounds+0x110/0x1a4
[c00000000101be20] [c000000000d21760] .early_init_mmu+0x1b4/0x5a0
[c00000000101bf10] [c000000000d1ba28] .early_setup+0x100/0x130
[c00000000101bf90] [c000000000000528] start_here_multiplatform+0x68/0x80
================================================================================
Fix this by first checking if the element exists (shift != 0) before
constructing the constant.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit f9bc28aedfb5bbd572d2d365f3095c1becd7209b ]
If an error occurs during an unplug operation, it's possible for
eeh_dump_dev_log() to be called when edev->pdn is null, which
currently leads to dereferencing a null pointer.
Handle this by skipping the error log for those devices.
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 960e30029863db95ec79a71009272d4661db5991 ]
Ever since commit 15a3204d24a3 ("powerpc/64s: Set assembler machine type
to POWER4") we force -mpower4 to be passed to the assembler
irrespective of the CFLAGS used (for Book3s 64).
When building a powerpc64 kernel with clang, clang will not add -many
to the assembler flags, so any instructions that the compiler has
generated that are not available on power4 will cause an error:
/usr/bin/as -a64 -mppc64 -mlittle-endian -mpower8 \
-I ./arch/powerpc/include -I ./arch/powerpc/include/generated \
-I ./include -I ./arch/powerpc/include/uapi \
-I ./arch/powerpc/include/generated/uapi -I ./include/uapi \
-I ./include/generated/uapi -I arch/powerpc -I arch/powerpc \
-maltivec -mpower4 -o init/do_mounts.o /tmp/do_mounts-3b0a3d.s
/tmp/do_mounts-51ce54.s:748: Error: unrecognized opcode: `isel'
GCC does include -many, so the GCC driven gas call will succeed:
as -v -I ./arch/powerpc/include -I ./arch/powerpc/include/generated -I
./include -I ./arch/powerpc/include/uapi
-I ./arch/powerpc/include/generated/uapi -I ./include/uapi
-I ./include/generated/uapi -I arch/powerpc -I arch/powerpc
-a64 -mpower8 -many -mlittle -maltivec -mpower4 -o init/do_mounts.o
Note that isel is power7 and above for IBM CPUs. GCC only generates it
for Power9 and above, but the above test was run against the clang
generated assembly.
Peter Bergner explains:
When using -many -mpower4, gas will first try and find a matching
power4 mnemonic and failing that, it will then allow any valid
mnemonic that gas knows about. GCC's use of -many predates me
though.
IIRC, Alan looked at trying to remove it, but I forget why he
didn't. Could be either a gcc or gas issue at the time. I'm not sure
whether issue still exists or not. He and I have modified how gas
works internally a fair amount since he tried removing gcc use of
-many.
I will also note that when using -many, gas will choose the first
mnemonic that matches in the mnemonic table and we have (mostly)
sorted the table so that server mnemonics show up earlier in the
table than other mnemonics, so they'll be seen/chosen first.
By explicitly setting -many we can build with Clang and GCC while
retaining the -mpower4 option.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 37e9c674e7e6f445e12cb1151017bd4bacdd1e2d ]
This patch fixes the following warnings (obtained with make W=1).
arch/powerpc/mm/slice.c: In function 'slice_range_to_mask':
arch/powerpc/mm/slice.c:73:12: error: comparison is always true due to limited range of data type [-Werror=type-limits]
if (start < SLICE_LOW_TOP) {
^
arch/powerpc/mm/slice.c:81:20: error: comparison is always false due to limited range of data type [-Werror=type-limits]
if ((start + len) > SLICE_LOW_TOP) {
^
arch/powerpc/mm/slice.c: In function 'slice_mask_for_free':
arch/powerpc/mm/slice.c:136:17: error: comparison is always true due to limited range of data type [-Werror=type-limits]
if (high_limit <= SLICE_LOW_TOP)
^
arch/powerpc/mm/slice.c: In function 'slice_check_range_fits':
arch/powerpc/mm/slice.c:185:12: error: comparison is always true due to limited range of data type [-Werror=type-limits]
if (start < SLICE_LOW_TOP) {
^
arch/powerpc/mm/slice.c:195:39: error: comparison is always false due to limited range of data type [-Werror=type-limits]
if (SLICE_NUM_HIGH && ((start + len) > SLICE_LOW_TOP)) {
^
arch/powerpc/mm/slice.c: In function 'slice_scan_available':
arch/powerpc/mm/slice.c:306:11: error: comparison is always true due to limited range of data type [-Werror=type-limits]
if (addr < SLICE_LOW_TOP) {
^
arch/powerpc/mm/slice.c: In function 'get_slice_psize':
arch/powerpc/mm/slice.c:709:11: error: comparison is always true due to limited range of data type [-Werror=type-limits]
if (addr < SLICE_LOW_TOP) {
^
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 0d923962ab69c27cca664a2d535e90ef655110ca ]
When we're running on Book3S with the Radix MMU enabled the page table
dump currently prints the wrong addresses because it uses the wrong
start address.
Fix it to use PAGE_OFFSET rather than KERN_VIRT_START.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit b851ba02a6f3075f0f99c60c4bc30a4af80cf428 ]
The recent module relocation overflow crash demonstrated that we
have no range checking on REL32 relative relocations. This patch
implements a basic check, the same kernel that previously oopsed
and rebooted now continues with some of these errors when loading
the module:
module_64: x_tables: REL32 527703503449812 out of range!
Possibly other relocations (ADDR32, REL16, TOC16, etc.) should also have
overflow checks.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit daf00ae71dad8aa05965713c62558aeebf2df48e ]
commit b96672dd840f ("powerpc: Machine check interrupt is a non-
maskable interrupt") added a call to nmi_enter() at the beginning of
machine check restart exception handler. Due to that, in_interrupt()
always returns true regardless of the state before entering the
exception, and die() panics even when the system was not already in
interrupt.
This patch calls nmi_exit() before calling die() in order to restore
the interrupt state we had before calling nmi_enter()
Fixes: b96672dd840f ("powerpc: Machine check interrupt is a non-maskable interrupt")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit bc276ecba132caccb1fda5863a652c15def2b8c6 upstream.
PPC_INVALIDATE_ERAT is slbia IH=7 which is a new variant introduced
with POWER9, and the result is undefined on earlier CPUs.
Commits 7b9f71f974 ("powerpc/64s: POWER9 machine check handler") and
d4748276ae ("powerpc/64s: Improve local TLB flush for boot and MCE on
POWER9") caused POWER7/8 code to use this instruction. Remove it. An
ERAT flush can be made by invalidatig the SLB, but before POWER9 that
requires a flush and rebolt.
Fixes: 7b9f71f974 ("powerpc/64s: POWER9 machine check handler")
Fixes: d4748276ae ("powerpc/64s: Improve local TLB flush for boot and MCE on POWER9")
Cc: stable@vger.kernel.org # v4.11+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit dd9a8c5a87395b6f05552c3b44e42fdc95760552 upstream.
Currently on P9N DD2.1 we end up taking infinite TM facility
unavailable exceptions on the first TM usage by userspace.
In the special case of TM no suspend (P9N DD2.1), Linux is told TM is
off via CPU dt-ftrs but told to (partially) use it via
OPAL_REINIT_CPUS_TM_SUSPEND_DISABLED. So HFSCR[TM] will be off from
dt-ftrs but we need to turn it on for the no suspend case.
This patch fixes this by enabling HFSCR TM in this case.
Cc: stable@vger.kernel.org # 4.15+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 0f99153def98134403c9149128e59d3e1786cf04 upstream.
mpic_get_primary_version() is not defined when not using MPIC.
The compile error log like:
arch/powerpc/sysdev/built-in.o: In function `fsl_of_msi_probe':
fsl_msi.c:(.text+0x150c): undefined reference to `fsl_mpic_primary_get_version'
Signed-off-by: Jia Hongtao <hongtao.jia@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Reported-by: Radu Rendec <radu.rendec@gmail.com>
Fixes: 807d38b73b6 ("powerpc/mpic: Add get_version API both for internal and external use")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 59fe7eaf3598a89cbcd72e645b1d08afd76f7b29 upstream.
module_frob_arch_sections() is called before the module is moved to its
final location. The function descriptor section addresses we are setting
here are thus invalid. Fix this by processing opd section during
module_finalize()
Fixes: 5633e85b2c313 ("powerpc64: Add .opd based function descriptor dereference")
Cc: stable@vger.kernel.org # v4.16
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Implement the powerpc pieces for lazy preempt.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Upstream uses arch_spinlock_t within spinlock_t and requests that
spinlock_types.h header file is included first.
On -RT we have the rt_mutex with its raw_lock wait_lock which needs
architectures' spinlock_types.h header file for its definition. However
we need rt_mutex first because it is used to build the spinlock_t so
that check does not work for us.
Therefore I am dropping that check.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
|
|
Disable extra stacks for softirqs. We want to preempt softirqs and
having them on special IRQ-stack does not make this easier.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
|
Completions have no long lasting callbacks and therefor do not need
the complex waitqueue variant. Use simple waitqueues which reduces the
contention on the waitqueue lock.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
|
The current highmem handling on -RT is not compatible and needs fixups.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
|
While converting the openpic emulation code to use a raw_spinlock_t enables
guests to run on RT, there's still a performance issue. For interrupts sent in
directed delivery mode with a multiple CPU mask, the emulated openpic will loop
through all of the VCPUs, and for each VCPUs, it call IRQ_check, which will loop
through all the pending interrupts for that VCPU. This is done while holding the
raw_lock, meaning that in all this time the interrupts and preemption are
disabled on the host Linux. A malicious user app can max both these number and
cause a DoS.
This temporary fix is sent for two reasons. First is so that users who want to
use the in-kernel MPIC emulation are aware of the potential latencies, thus
making sure that the hardware MPIC and their usage scenario does not involve
interrupts sent in directed delivery mode, and the number of possible pending
interrupts is kept small. Secondly, this should incentivize the development of a
proper openpic emulation that would be better suited for RT.
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Bogdan Purcareata <bogdan.purcareata@freescale.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
|
|
Use generic code which uses rtmutex
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
|
In commit 4b53a3412d66 ("sched/core: Remove the tsk_nr_cpus_allowed()
wrapper") the tsk_nr_cpus_allowed() wrapper was removed. There was not
much difference in !RT but in RT we used this to implement
migrate_disable(). Within a migrate_disable() section the CPU mask is
restricted to single CPU while the "normal" CPU mask remains untouched.
As an alternative implementation Ingo suggested to use
struct task_struct {
const cpumask_t *cpus_ptr;
cpumask_t cpus_mask;
};
with
t->cpus_allowed_ptr = &t->cpus_allowed;
In -RT we then can switch the cpus_ptr to
t->cpus_allowed_ptr = &cpumask_of(task_cpu(p));
in a migration disabled region. The rules are simple:
- Code that 'uses' ->cpus_allowed would use the pointer.
- Code that 'modifies' ->cpus_allowed would use the direct mask.
While converting the existing users I tried to stick with the rules
above however… well mostly CPUFREQ tries to temporary switch the CPU
mask to do something on a certain CPU and then switches the mask back it
its original value. So in theory `cpus_ptr' could or should be used.
However if this is invoked in a migration disabled region (which is not
the case because it would require something like preempt_disable() and
set_cpus_allowed_ptr() might sleep so it can't be) then the "restore"
part would restore the wrong mask. So it only looks strange and I go for
the pointer…
Some drivers copy the cpumask without cpumask_copy() and others use
cpumask_copy but without alloc_cpumask_var(). I did not fix those as
part of this, could do this as a follow up…
So is this the way we want it?
Is the usage of `cpus_ptr' vs `cpus_mask' for the set + restore part
(see cpufreq users) what we want? At some point it looks like they
should use a different interface for their doing. I am not sure why
switching to certain CPU is important but maybe it could be done via a
workqueue from the CPUFREQ core (so we have a comment desribing why are
doing this and a get_online_cpus() to ensure that the CPU does not go
offline too early).
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Dan writes:
"libnvdimm/dax 4.19-rc8
* Fix a livelock in dax_layout_busy_page() present since v4.18. The
lockup triggers when truncating an actively mapped huge page out of
a mapping pinned for direct-I/O.
* Fix mprotect() clobbers of _PAGE_DEVMAP. Broken since v4.5
mprotect() clears this flag that is needed to communicate the
liveness of device pages to the get_user_pages() path."
* tag 'libnvdimm-fixes-4.19-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
mm: Preserve _PAGE_DEVMAP across mprotect() calls
filesystem-dax: Fix dax_layout_busy_page() livelock
|
|
Currently _PAGE_DEVMAP bit is not preserved in mprotect(2) calls. As a
result we will see warnings such as:
BUG: Bad page map in process JobWrk0013 pte:800001803875ea25 pmd:7624381067
addr:00007f0930720000 vm_flags:280000f9 anon_vma: (null) mapping:ffff97f2384056f0 index:0
file:457-000000fe00000030-00000009-000000ca-00000001_2001.fileblock fault:xfs_filemap_fault [xfs] mmap:xfs_file_mmap [xfs] readpage: (null)
CPU: 3 PID: 15848 Comm: JobWrk0013 Tainted: G W 4.12.14-2.g7573215-default #1 SLE12-SP4 (unreleased)
Hardware name: Intel Corporation S2600WFD/S2600WFD, BIOS SE5C620.86B.01.00.0833.051120182255 05/11/2018
Call Trace:
dump_stack+0x5a/0x75
print_bad_pte+0x217/0x2c0
? enqueue_task_fair+0x76/0x9f0
_vm_normal_page+0xe5/0x100
zap_pte_range+0x148/0x740
unmap_page_range+0x39a/0x4b0
unmap_vmas+0x42/0x90
unmap_region+0x99/0xf0
? vma_gap_callbacks_rotate+0x1a/0x20
do_munmap+0x255/0x3a0
vm_munmap+0x54/0x80
SyS_munmap+0x1d/0x30
do_syscall_64+0x74/0x150
entry_SYSCALL_64_after_hwframe+0x3d/0xa2
...
when mprotect(2) gets used on DAX mappings. Also there is a wide variety
of other failures that can result from the missing _PAGE_DEVMAP flag
when the area gets used by get_user_pages() later.
Fix the problem by including _PAGE_DEVMAP in a set of flags that get
preserved by mprotect(2).
Fixes: 69660fd797c3 ("x86, mm: introduce _PAGE_DEVMAP")
Fixes: ebd31197931d ("powerpc/mm: Add devmap support for ppc64")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
|
|
https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Michael writes:
"powerpc fixes for 4.19 #4
Four regression fixes.
A fix for a change to lib/xz which broke our zImage loader when
building with XZ compression. OK'ed by Herbert who merged the
original patch.
The recent fix we did to avoid patching __init text broke some 32-bit
machines, fix that.
Our show_user_instructions() could be tricked into printing kernel
memory, add a check to avoid that.
And a fix for a change to our NUMA initialisation logic, which causes
crashes in some kdump configurations.
Thanks to:
Christophe Leroy, Hari Bathini, Jann Horn, Joel Stanley, Meelis
Roos, Murilo Opsfelder Araujo, Srikar Dronamraju."
* tag 'powerpc-4.19-4' of https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/numa: Skip onlining a offline node in kdump path
powerpc: Don't print kernel instructions in show_user_instructions()
powerpc/lib: fix book3s/32 boot failure due to code patching
lib/xz: Put CRC32_POLY_LE in xz_private.h
|
|
Paolo writes:
"KVM changes for 4.19-rc7
x86 and PPC bugfixes, mostly introduced in 4.19-rc1."
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
kvm: nVMX: fix entry with pending interrupt if APICv is enabled
KVM: VMX: hide flexpriority from guest when disabled at the module level
KVM: VMX: check for existence of secondary exec controls before accessing
KVM: PPC: Book3S HV: Avoid crash from THP collapse during radix page fault
KVM: x86: fix L1TF's MMIO GFN calculation
tools/kvm_stat: cut down decimal places in update interval dialog
KVM: nVMX: Fix emulation of VM_ENTRY_LOAD_BNDCFGS
KVM: x86: Do not use kvm_x86_ops->mpx_supported() directly
KVM: nVMX: Do not expose MPX VMX controls when guest MPX disabled
KVM: x86: never trap MSR_KERNEL_GS_BASE
|
|
With commit 2ea626306810 ("powerpc/topology: Get topology for shared
processors at boot"), kdump kernel on shared LPAR may crash.
The necessary conditions are
- Shared LPAR with at least 2 nodes having memory and CPUs.
- Memory requirement for kdump kernel must be met by the first N-1
nodes where there are at least N nodes with memory and CPUs.
Example numactl of such a machine.
$ numactl -H
available: 5 nodes (0,2,5-7)
node 0 cpus:
node 0 size: 0 MB
node 0 free: 0 MB
node 2 cpus:
node 2 size: 255 MB
node 2 free: 189 MB
node 5 cpus: 24 25 26 27 28 29 30 31
node 5 size: 4095 MB
node 5 free: 4024 MB
node 6 cpus: 0 1 2 3 4 5 6 7 16 17 18 19 20 21 22 23
node 6 size: 6353 MB
node 6 free: 5998 MB
node 7 cpus: 8 9 10 11 12 13 14 15 32 33 34 35 36 37 38 39
node 7 size: 7640 MB
node 7 free: 7164 MB
node distances:
node 0 2 5 6 7
0: 10 40 40 40 40
2: 40 10 40 40 40
5: 40 40 10 40 40
6: 40 40 40 10 20
7: 40 40 40 20 10
Steps to reproduce.
1. Load / start kdump service.
2. Trigger a kdump (for example : echo c > /proc/sysrq-trigger)
When booting a kdump kernel with 2048M:
kexec: Starting switchover sequence.
I'm in purgatory
Using 1TB segments
hash-mmu: Initializing hash mmu with SLB
Linux version 4.19.0-rc5-master+ (srikar@linux-xxu6) (gcc version 4.8.5 (SUSE Linux)) #1 SMP Thu Sep 27 19:45:00 IST 2018
Found initrd at 0xc000000009e70000:0xc00000000ae554b4
Using pSeries machine description
-----------------------------------------------------
ppc64_pft_size = 0x1e
phys_mem_size = 0x88000000
dcache_bsize = 0x80
icache_bsize = 0x80
cpu_features = 0x000000ff8f5d91a7
possible = 0x0000fbffcf5fb1a7
always = 0x0000006f8b5c91a1
cpu_user_features = 0xdc0065c2 0xef000000
mmu_features = 0x7c006001
firmware_features = 0x00000007c45bfc57
htab_hash_mask = 0x7fffff
physical_start = 0x8000000
-----------------------------------------------------
numa: NODE_DATA [mem 0x87d5e300-0x87d67fff]
numa: NODE_DATA(0) on node 6
numa: NODE_DATA [mem 0x87d54600-0x87d5e2ff]
Top of RAM: 0x88000000, Total RAM: 0x88000000
Memory hole size: 0MB
Zone ranges:
DMA [mem 0x0000000000000000-0x0000000087ffffff]
DMA32 empty
Normal empty
Movable zone start for each node
Early memory node ranges
node 6: [mem 0x0000000000000000-0x0000000087ffffff]
Could not find start_pfn for node 0
Initmem setup node 0 [mem 0x0000000000000000-0x0000000000000000]
On node 0 totalpages: 0
Initmem setup node 6 [mem 0x0000000000000000-0x0000000087ffffff]
On node 6 totalpages: 34816
Unable to handle kernel paging request for data at address 0x00000060
Faulting instruction address: 0xc000000008703a54
Oops: Kernel access of bad area, sig: 11 [#1]
LE SMP NR_CPUS=2048 NUMA pSeries
Modules linked in:
CPU: 11 PID: 1 Comm: swapper/11 Not tainted 4.19.0-rc5-master+ #1
NIP: c000000008703a54 LR: c000000008703a38 CTR: 0000000000000000
REGS: c00000000b673440 TRAP: 0380 Not tainted (4.19.0-rc5-master+)
MSR: 8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 24022022 XER: 20000002
CFAR: c0000000086fc238 IRQMASK: 0
GPR00: c000000008703a38 c00000000b6736c0 c000000009281900 0000000000000000
GPR04: 0000000000000000 0000000000000000 fffffffffffff001 c00000000b660080
GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000220
GPR12: 0000000000002200 c000000009e51400 0000000000000000 0000000000000008
GPR16: 0000000000000000 c000000008c152e8 c000000008c152a8 0000000000000000
GPR20: c000000009422fd8 c000000009412fd8 c000000009426040 0000000000000008
GPR24: 0000000000000000 0000000000000000 c000000009168bc8 c000000009168c78
GPR28: c00000000b126410 0000000000000000 c00000000916a0b8 c00000000b126400
NIP [c000000008703a54] bus_add_device+0x84/0x1e0
LR [c000000008703a38] bus_add_device+0x68/0x1e0
Call Trace:
[c00000000b6736c0] [c000000008703a38] bus_add_device+0x68/0x1e0 (unreliable)
[c00000000b673740] [c000000008700194] device_add+0x454/0x7c0
[c00000000b673800] [c00000000872e660] __register_one_node+0xb0/0x240
[c00000000b673860] [c00000000839a6bc] __try_online_node+0x12c/0x180
[c00000000b673900] [c00000000839b978] try_online_node+0x58/0x90
[c00000000b673930] [c0000000080846d8] find_and_online_cpu_nid+0x158/0x190
[c00000000b673a10] [c0000000080848a0] numa_update_cpu_topology+0x190/0x580
[c00000000b673c00] [c000000008d3f2e4] smp_cpus_done+0x94/0x108
[c00000000b673c70] [c000000008d5c00c] smp_init+0x174/0x19c
[c00000000b673d00] [c000000008d346b8] kernel_init_freeable+0x1e0/0x450
[c00000000b673dc0] [c0000000080102e8] kernel_init+0x28/0x160
[c00000000b673e30] [c00000000800b65c] ret_from_kernel_thread+0x5c/0x80
Instruction dump:
60000000 60000000 e89e0020 7fe3fb78 4bff87d5 60000000 7c7d1b79 4082008c
e8bf0050 e93e0098 3b9f0010 2fa50000 <e8690060> 38630018 419e0114 7f84e378
---[ end trace 593577668c2daa65 ]---
However a regular kernel with 4096M (2048 gets reserved for crash
kernel) boots properly.
Unlike regular kernels, which mark all available nodes as online,
kdump kernel only marks just enough nodes as online and marks the rest
as offline at boot. However kdump kernel boots with all available
CPUs. With Commit 2ea626306810 ("powerpc/topology: Get topology for
shared processors at boot"), all CPUs are onlined on their respective
nodes at boot time. try_online_node() tries to online the offline
nodes but fails as all needed subsystems are not yet initialized.
As part of fix, detect and skip early onlining of a offline node.
Fixes: 2ea626306810 ("powerpc/topology: Get topology for shared processors at boot")
Reported-by: Pavithra Prakash <pavrampu@in.ibm.com>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Recently we implemented show_user_instructions() which dumps the code
around the NIP when a user space process dies with an unhandled
signal. This was modelled on the x86 code, and we even went so far as
to implement the exact same bug, namely that if the user process
crashed with its NIP pointing into the kernel we will dump kernel text
to dmesg. eg:
bad-bctr[2996]: segfault (11) at c000000000010000 nip c000000000010000 lr 12d0b0894 code 1
bad-bctr[2996]: code: fbe10068 7cbe2b78 7c7f1b78 fb610048 38a10028 38810020 fb810050 7f8802a6
bad-bctr[2996]: code: 3860001c f8010080 48242371 60000000 <7c7b1b79> 4082002c e8010080 eb610048
This was discovered on x86 by Jann Horn and fixed in commit
342db04ae712 ("x86/dumpstack: Don't dump kernel memory based on usermode RIP").
Fix it by checking the adjusted NIP value (pc) and number of
instructions against USER_DS, and bail if we fail the check, eg:
bad-bctr[2969]: segfault (11) at c000000000010000 nip c000000000010000 lr 107930894 code 1
bad-bctr[2969]: Bad NIP, not dumping instructions.
Fixes: 88b0fe175735 ("powerpc: Add show_user_instructions()")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Commit 71d29f43b633 ("KVM: PPC: Book3S HV: Don't use compound_order to
determine host mapping size", 2018-09-11) added a call to
__find_linux_pte() and a dereference of the returned PTE pointer to the
radix page fault path in the common case where the page is normal
system memory. Previously, __find_linux_pte() was only called for
mappings to physical addresses which don't have a page struct (e.g.
memory-mapped I/O) or where the page struct is marked as reserved
memory.
This exposes us to the possibility that the returned PTE pointer
could be NULL, for example in the case of a concurrent THP collapse
operation. Dereferencing the returned NULL pointer causes a host
crash.
To fix this, we check for NULL, and if it is NULL, we retry the
operation by returning to the guest, with the expectation that it
will generate the same page fault again (unless of course it has
been fixed up by another CPU in the meantime).
Fixes: 71d29f43b633 ("KVM: PPC: Book3S HV: Don't use compound_order to determine host mapping size")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
Commit 51c3c62b58b3 ("powerpc: Avoid code patching freed init
sections") accesses 'init_mem_is_free' flag too early, before the
kernel is relocated. This provokes early boot failure (before the
console is active).
As it is not necessary to do this verification that early, this
patch moves the test into patch_instruction() instead of
__patch_instruction().
This modification also has the advantage of avoiding unnecessary
remappings.
Fixes: 51c3c62b58b3 ("powerpc: Avoid code patching freed init sections")
Cc: stable@vger.kernel.org # 4.13+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Michael writes:
"powerpc fixes for 4.19 #3
A reasonably big batch of fixes due to me being away for a few weeks.
A fix for the TM emulation support on Power9, which could result in
corrupting the guest r11 when running under KVM.
Two fixes to the TM code which could lead to userspace GPR corruption
if we take an SLB miss at exactly the wrong time.
Our dynamic patching code had a bug that meant we could patch freed
__init text, which could lead to corrupting userspace memory.
csum_ipv6_magic() didn't work on little endian platforms since we
optimised it recently.
A fix for an endian bug when reading a device tree property telling
us how many storage keys the machine has available.
Fix a crash seen on some configurations of PowerVM when migrating the
partition from one machine to another.
A fix for a regression in the setup of our CPU to NUMA node mapping
in KVM guests.
A fix to our selftest Makefiles to make them work since a recent
change to the shared Makefile logic."
* tag 'powerpc-4.19-3' of https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
selftests/powerpc: Fix Makefiles for headers_install change
powerpc/numa: Use associativity if VPHN hcall is successful
powerpc/tm: Avoid possible userspace r1 corruption on reclaim
powerpc/tm: Fix userspace r13 corruption
powerpc/pseries: Fix unitialized timer reset on migration
powerpc/pkeys: Fix reading of ibm, processor-storage-keys property
powerpc: fix csum_ipv6_magic() on little endian platforms
powerpc/powernv/ioda2: Reduce upper limit for DMA window size (again)
powerpc: Avoid code patching freed init sections
KVM: PPC: Book3S HV: Fix guest r11 corruption with POWER9 TM workarounds
|
|
Currently associativity is used to lookup node-id even if the
preceding VPHN hcall failed. However this can cause CPU to be made
part of the wrong node, (most likely to be node 0). This is because
VPHN is not enabled on KVM guests.
With 2ea6263 ("powerpc/topology: Get topology for shared processors at
boot"), associativity is used to set to the wrong node. Hence KVM
guest topology is broken.
For example : A 4 node KVM guest before would have reported.
[root@localhost ~]# numactl -H
available: 4 nodes (0-3)
node 0 cpus: 0 1 2 3
node 0 size: 1746 MB
node 0 free: 1604 MB
node 1 cpus: 4 5 6 7
node 1 size: 2044 MB
node 1 free: 1765 MB
node 2 cpus: 8 9 10 11
node 2 size: 2044 MB
node 2 free: 1837 MB
node 3 cpus: 12 13 14 15
node 3 size: 2044 MB
node 3 free: 1903 MB
node distances:
node 0 1 2 3
0: 10 40 40 40
1: 40 10 40 40
2: 40 40 10 40
3: 40 40 40 10
Would now report:
[root@localhost ~]# numactl -H
available: 4 nodes (0-3)
node 0 cpus: 0 2 3 4 5 6 7 8 9 10 11 12 13 14 15
node 0 size: 1746 MB
node 0 free: 1244 MB
node 1 cpus:
node 1 size: 2044 MB
node 1 free: 2032 MB
node 2 cpus: 1
node 2 size: 2044 MB
node 2 free: 2028 MB
node 3 cpus:
node 3 size: 2044 MB
node 3 free: 2032 MB
node distances:
node 0 1 2 3
0: 10 40 40 40
1: 40 10 40 40
2: 40 40 10 40
3: 40 40 40 10
Fix this by skipping associativity lookup if the VPHN hcall failed.
Fixes: 2ea626306810 ("powerpc/topology: Get topology for shared processors at boot")
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Current we store the userspace r1 to PACATMSCRATCH before finally
saving it to the thread struct.
In theory an exception could be taken here (like a machine check or
SLB miss) that could write PACATMSCRATCH and hence corrupt the
userspace r1. The SLB fault currently doesn't touch PACATMSCRATCH, but
others do.
We've never actually seen this happen but it's theoretically
possible. Either way, the code is fragile as it is.
This patch saves r1 to the kernel stack (which can't fault) before we
turn MSR[RI] back on. PACATMSCRATCH is still used but only with
MSR[RI] off. We then copy r1 from the kernel stack to the thread
struct once we have MSR[RI] back on.
Suggested-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
When we treclaim we store the userspace checkpointed r13 to a scratch
SPR and then later save the scratch SPR to the user thread struct.
Unfortunately, this doesn't work as accessing the user thread struct
can take an SLB fault and the SLB fault handler will write the same
scratch SPRG that now contains the userspace r13.
To fix this, we store r13 to the kernel stack (which can't fault)
before we access the user thread struct.
Found by running P8 guest + powervm + disable_1tb_segments + TM. Seen
as a random userspace segfault with r13 looking like a kernel address.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
After migration of a powerpc LPAR, the kernel executes code to
update the system state to reflect new platform characteristics.
Such changes include modifications to device tree properties provided
to the system by PHYP. Property notifications received by the
post_mobility_fixup() code are passed along to the kernel in general
through a call to of_update_property() which in turn passes such
events back to all modules through entries like the '.notifier_call'
function within the NUMA module.
When the NUMA module updates its state, it resets its event timer. If
this occurs after a previous call to stop_topology_update() or on a
system without VPHN enabled, the code runs into an unitialized timer
structure and crashes. This patch adds a safety check along this path
toward the problem code.
An example crash log is as follows.
ibmvscsi 30000081: Re-enabling adapter!
------------[ cut here ]------------
kernel BUG at kernel/time/timer.c:958!
Oops: Exception in kernel mode, sig: 5 [#1]
LE SMP NR_CPUS=2048 NUMA pSeries
Modules linked in: nfsv3 nfs_acl nfs tcp_diag udp_diag inet_diag lockd unix_diag af_packet_diag netlink_diag grace fscache sunrpc xts vmx_crypto pseries_rng sg binfmt_misc ip_tables xfs libcrc32c sd_mod ibmvscsi ibmveth scsi_transport_srp dm_mirror dm_region_hash dm_log dm_mod
CPU: 11 PID: 3067 Comm: drmgr Not tainted 4.17.0+ #179
...
NIP mod_timer+0x4c/0x400
LR reset_topology_timer+0x40/0x60
Call Trace:
0xc0000003f9407830 (unreliable)
reset_topology_timer+0x40/0x60
dt_update_callback+0x100/0x120
notifier_call_chain+0x90/0x100
__blocking_notifier_call_chain+0x60/0x90
of_property_notify+0x90/0xd0
of_update_property+0x104/0x150
update_dt_property+0xdc/0x1f0
pseries_devicetree_update+0x2d0/0x510
post_mobility_fixup+0x7c/0xf0
migration_store+0xa4/0xc0
kobj_attr_store+0x30/0x60
sysfs_kf_write+0x64/0xa0
kernfs_fop_write+0x16c/0x240
__vfs_write+0x40/0x200
vfs_write+0xc8/0x240
ksys_write+0x5c/0x100
system_call+0x58/0x6c
Fixes: 5d88aa85c00b ("powerpc/pseries: Update CPU maps when device tree is updated")
Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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scan_pkey_feature() uses of_property_read_u32_array() to read the
ibm,processor-storage-keys property and calls be32_to_cpu() on the
value it gets. The problem is that of_property_read_u32_array() already
returns the value converted to the CPU byte order.
The value of pkeys_total ends up more or less sane because there's a min()
call in pkey_initialize() which reduces pkeys_total to 32. So in practice
the kernel ignores the fact that the hypervisor reserved one key for
itself (the device tree advertises 31 keys in my test VM).
This is wrong, but the effect in practice is that when a process tries to
allocate the 32nd key, it gets an -EINVAL error instead of -ENOSPC which
would indicate that there aren't any keys available
Fixes: cf43d3b26452 ("powerpc: Enable pkey subsystem")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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On little endian platforms, csum_ipv6_magic() keeps len and proto in
CPU byte order. This generates a bad results leading to ICMPv6 packets
from other hosts being dropped by powerpc64le platforms.
In order to fix this, len and proto should be converted to network
byte order ie bigendian byte order. However checksumming 0x12345678
and 0x56341278 provide the exact same result so it is enough to
rotate the sum of len and proto by 1 byte.
PPC32 only support bigendian so the fix is needed for PPC64 only
Fixes: e9c4943a107b ("powerpc: Implement csum_ipv6_magic in assembly")
Reported-by: Jianlin Shi <jishi@redhat.com>
Reported-by: Xin Long <lucien.xin@gmail.com>
Cc: <stable@vger.kernel.org> # 4.18+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Tested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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mpe: This was fixed originally in commit d3d4ffaae439
("powerpc/powernv/ioda2: Reduce upper limit for DMA window size"), but
contrary to what the merge commit says was inadvertently lost by me in
commit ce57c6610cc2 ("Merge branch 'topic/ppc-kvm' into next") which
brought in changes that moved the code to a new file. So reapply it to
the new file.
Original commit message follows:
We use PHB in mode1 which uses bit 59 to select a correct DMA window.
However there is mode2 which uses bits 59:55 and allows up to 32 DMA
windows per a PE.
Even though documentation does not clearly specify that, it seems that
the actual hardware does not support bits 59:55 even in mode1, in
other words we can create a window as big as 1<<58 but DMA simply
won't work.
This reduces the upper limit from 59 to 55 bits to let the userspace
know about the hardware limits.
Fixes: ce57c6610cc2 ("Merge branch 'topic/ppc-kvm' into next")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This stops us from doing code patching in init sections after they've
been freed.
In this chain:
kvm_guest_init() ->
kvm_use_magic_page() ->
fault_in_pages_readable() ->
__get_user() ->
__get_user_nocheck() ->
barrier_nospec();
We have a code patching location at barrier_nospec() and
kvm_guest_init() is an init function. This whole chain gets inlined,
so when we free the init section (hence kvm_guest_init()), this code
goes away and hence should no longer be patched.
We seen this as userspace memory corruption when using a memory
checker while doing partition migration testing on powervm (this
starts the code patching post migration via
/sys/kernel/mobility/migration). In theory, it could also happen when
using /sys/kernel/debug/powerpc/barrier_nospec.
Cc: stable@vger.kernel.org # 4.13+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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When we come into the softpatch handler (0x1500), we use r11 to store
the HSRR0 for later use by the denorm handler.
We also use the softpatch handler for the TM workarounds for
POWER9. Unfortunately, in kvmppc_interrupt_hv we later store r11 out
to the vcpu assuming it's still what we got from userspace.
This causes r11 to be corrupted in the VCPU and hence when we restore
the guest, we get a corrupted r11. We've seen this when running TM
tests inside guests on P9.
This fixes the problem by only touching r11 in the denorm case.
Fixes: 4bb3c7a020 ("KVM: PPC: Book3S HV: Work around transactional memory bugs in POWER9")
Cc: <stable@vger.kernel.org> # 4.17+
Test-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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THP paths can defer splitting compound pages until after the actual
remap and TLB flushes to split a huge PMD/PUD. This causes radix
partition scope page table mappings to get out of synch with the host
qemu page table mappings.
This results in random memory corruption in the guest when running
with THP. The easiest way to reproduce is use KVM balloon to free up
a lot of memory in the guest and then shrink the balloon to give the
memory back, while some work is being done in the guest.
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: kvm-ppc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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At the moment the real mode handler of H_PUT_TCE calls iommu_tce_xchg_rm()
which in turn reads the old TCE and if it was a valid entry, marks
the physical page dirty if it was mapped for writing. Since it is in
real mode, realmode_pfn_to_page() is used instead of pfn_to_page()
to get the page struct. However SetPageDirty() itself reads the compound
page head and returns a virtual address for the head page struct and
setting dirty bit for that kills the system.
This adds additional dirty bit tracking into the MM/IOMMU API for use
in the real mode. Note that this does not change how VFIO and
KVM (in virtual mode) set this bit. The KVM (real mode) changes include:
- use the lowest bit of the cached host phys address to carry
the dirty bit;
- mark pages dirty when they are unpinned which happens when
the preregistered memory is released which always happens in virtual
mode;
- add mm_iommu_ua_mark_dirty_rm() helper to set delayed dirty bit;
- change iommu_tce_xchg_rm() to take the kvm struct for the mm to use
in the new mm_iommu_ua_mark_dirty_rm() helper;
- move iommu_tce_xchg_rm() to book3s_64_vio_hv.c (which is the only
caller anyway) to reduce the real mode KVM and IOMMU knowledge
across different subsystems.
This removes realmode_pfn_to_page() as it is not used anymore.
While we at it, remove some EXPORT_SYMBOL_GPL() as that code is for
the real mode only and modules cannot call it anyway.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux
KVM: s390: Fixes for 4.19
- Fallout from the hugetlbfs support: pfmf interpretion and locking
- VSIE: fix keywrapping for nested guests
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