[ Upstream commit 4ec5feec1ad029bdf7d49bc50ccc0c195eeabe93 ]
scv support introduced the notion of code that implicitly soft-masks
irqs due to the instruction addresses. This is required because scv
enters the kernel with MSR[EE]=1.
If a NMI (including soft-NMI) interrupt hits when we are implicitly
soft-masked then its regs->softe does not reflect this because it is
derived from the explicit soft mask state (paca->irq_soft_mask). This
makes arch_irq_disabled_regs(regs) return false.
This can trigger a warning in the soft-NMI watchdog code (shown below).
Fix it by having NMI interrupts set regs->softe to disabled in case of
interrupting an implicit soft-masked region.
------------[ cut here ]------------
WARNING: CPU: 41 PID: 1103 at arch/powerpc/kernel/watchdog.c:259 soft_nmi_interrupt+0x3e4/0x5f0
CPU: 41 PID: 1103 Comm: (spawn) Not tainted
NIP: c000000000039534 LR: c000000000039234 CTR: c000000000009a00
REGS: c000007fffbcf940 TRAP: 0700 Not tainted
MSR: 9000000000021033 <SF,HV,ME,IR,DR,RI,LE> CR: 22042482 XER: 200400ad
CFAR: c000000000039260 IRQMASK: 3
GPR00: c000000000039204 c000007fffbcfbe0 c000000001d6c300 0000000000000003
GPR04: 00007ffffa45d078 0000000000000000 0000000000000008 0000000000000020
GPR08: 0000007ffd4e0000 0000000000000000 c000007ffffceb00 7265677368657265
GPR12: 9000000000009033 c000007ffffceb00 00000f7075bf4480 000000000000002a
GPR16: 00000f705745a528 00007ffffa45ddd8 00000f70574d0008 0000000000000000
GPR20: 00000f7075c58d70 00000f7057459c38 0000000000000001 0000000000000040
GPR24: 0000000000000000 0000000000000029 c000000001dae058 0000000000000029
GPR28: 0000000000000000 0000000000000800 0000000000000009 c000007fffbcfd60
NIP [c000000000039534] soft_nmi_interrupt+0x3e4/0x5f0
LR [c000000000039234] soft_nmi_interrupt+0xe4/0x5f0
Call Trace:
[c000007fffbcfbe0] [c000000000039204] soft_nmi_interrupt+0xb4/0x5f0 (unreliable)
[c000007fffbcfcf0] [c00000000000c0e8] soft_nmi_common+0x138/0x1c4
--- interrupt: 900 at end_real_trampolines+0x0/0x1000
NIP: c000000000003000 LR: 00007ca426adb03c CTR: 900000000280f033
REGS: c000007fffbcfd60 TRAP: 0900
MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 44042482 XER: 200400ad
CFAR: 00007ca426946020 IRQMASK: 0
GPR00: 00000000000000ad 00007ffffa45d050 00007ca426b07f00 0000000000000035
GPR04: 00007ffffa45d078 0000000000000000 0000000000000008 0000000000000020
GPR08: 0000000000000000 0000000000100000 0000000010000000 00007ffffa45d110
GPR12: 0000000000000001 00007ca426d4e680 00000f7075bf4480 000000000000002a
GPR16: 00000f705745a528 00007ffffa45ddd8 00000f70574d0008 0000000000000000
GPR20: 00000f7075c58d70 00000f7057459c38 0000000000000001 0000000000000040
GPR24: 0000000000000000 00000f7057473f68 0000000000000003 000000000000041b
GPR28: 00007ffffa45d4c4 0000000000000035 0000000000000000 00000f7057473f68
NIP [c000000000003000] end_real_trampolines+0x0/0x1000
LR [00007ca426adb03c] 0x7ca426adb03c
--- interrupt: 900
Instruction dump:
60000000 60000000 60420000 38600001 482b3ae5 60000000 e93f0138 a36d0008
7daa6b78 71290001 7f7907b4 4082fd34 <0fe00000> 4bfffd2c 60420000 ea6100a8
---[ end trace dc75f67d819779da ]---
Fixes: 118178e62e2e ("powerpc: move NMI entry/exit code into wrapper")
Reported-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210503111708.758261-1-npiggin@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9ccba66d4d2aff9a3909aa77d57ea8b7cc166f3c ]
At the time being, the fixmap area is defined at the top of
the address space or just below KASAN.
This definition is not valid for PPC64.
For PPC64, use the top of the I/O space.
Because of circular dependencies, it is not possible to include
asm/fixmap.h in asm/book3s/64/pgtable.h , so define a fixed size
AREA at the top of the I/O space for fixmap and ensure during
build that the size is big enough.
Fixes: 265c3491c4bc ("powerpc: Add support for GENERIC_EARLY_IOREMAP")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0d51620eacf036d683d1a3c41328f69adb601dc0.1618925560.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c47f892d7aa62765bf0689073f75990b4517a4cf ]
Daniel reported that with Commit 4ca234a9cbd7 ("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: 4ca234a9cbd7 ("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
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b8b2f37cf632434456182e9002d63cbc4cccc50c ]
When adding a PTE a ptesync is needed to order the update of the PTE
with subsequent accesses otherwise a spurious fault may be raised.
radix__set_pte_at() does not do this for performance gains. For
non-kernel memory this is not an issue as any faults of this kind are
corrected by the page fault handler. For kernel memory these faults
are not handled. The current solution is that there is a ptesync in
flush_cache_vmap() which should be called when mapping from the
vmalloc region.
However, map_kernel_page() does not call flush_cache_vmap(). This is
troublesome in particular for code patching with Strict RWX on radix.
In do_patch_instruction() the page frame that contains the instruction
to be patched is mapped and then immediately patched. With no ordering
or synchronization between setting up the PTE and writing to the page
it is possible for faults.
As the code patching is done using __put_user_asm_goto() the resulting
fault is obscured - but using a normal store instead it can be seen:
BUG: Unable to handle kernel data access on write at 0xc008000008f24a3c
Faulting instruction address: 0xc00000000008bd74
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV
Modules linked in: nop_module(PO+) [last unloaded: nop_module]
CPU: 4 PID: 757 Comm: sh Tainted: P O 5.10.0-rc5-01361-ge3c1b78c8440-dirty #43
NIP: c00000000008bd74 LR: c00000000008bd50 CTR: c000000000025810
REGS: c000000016f634a0 TRAP: 0300 Tainted: P O (5.10.0-rc5-01361-ge3c1b78c8440-dirty)
MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 44002884 XER: 00000000
CFAR: c00000000007c68c DAR: c008000008f24a3c DSISR: 42000000 IRQMASK: 1
This results in the kind of issue reported here:
https://lore.kernel.org/linuxppc-dev/15AC5B0E-A221-4B8C-9039-FA96B8EF7C88@lca.pw/
Chris Riedl suggested a reliable way to reproduce the issue:
$ mount -t debugfs none /sys/kernel/debug
$ (while true; do echo function > /sys/kernel/debug/tracing/current_tracer ; echo nop > /sys/kernel/debug/tracing/current_tracer ; done) &
Turning ftrace on and off does a large amount of code patching which
in usually less then 5min will crash giving a trace like:
ftrace-powerpc: (____ptrval____): replaced (4b473b11) != old (60000000)
------------[ ftrace bug ]------------
ftrace failed to modify
[<c000000000bf8e5c>] napi_busy_loop+0xc/0x390
actual: 11:3b:47:4b
Setting ftrace call site to call ftrace function
ftrace record flags: 80000001
(1)
expected tramp: c00000000006c96c
------------[ cut here ]------------
WARNING: CPU: 4 PID: 809 at kernel/trace/ftrace.c:2065 ftrace_bug+0x28c/0x2e8
Modules linked in: nop_module(PO-) [last unloaded: nop_module]
CPU: 4 PID: 809 Comm: sh Tainted: P O 5.10.0-rc5-01360-gf878ccaf250a #1
NIP: c00000000024f334 LR: c00000000024f330 CTR: c0000000001a5af0
REGS: c000000004c8b760 TRAP: 0700 Tainted: P O (5.10.0-rc5-01360-gf878ccaf250a)
MSR: 900000000282b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 28008848 XER: 20040000
CFAR: c0000000001a9c98 IRQMASK: 0
GPR00: c00000000024f330 c000000004c8b9f0 c000000002770600 0000000000000022
GPR04: 00000000ffff7fff c000000004c8b6d0 0000000000000027 c0000007fe9bcdd8
GPR08: 0000000000000023 ffffffffffffffd8 0000000000000027 c000000002613118
GPR12: 0000000000008000 c0000007fffdca00 0000000000000000 0000000000000000
GPR16: 0000000023ec37c5 0000000000000000 0000000000000000 0000000000000008
GPR20: c000000004c8bc90 c0000000027a2d20 c000000004c8bcd0 c000000002612fe8
GPR24: 0000000000000038 0000000000000030 0000000000000028 0000000000000020
GPR28: c000000000ff1b68 c000000000bf8e5c c00000000312f700 c000000000fbb9b0
NIP ftrace_bug+0x28c/0x2e8
LR ftrace_bug+0x288/0x2e8
Call Trace:
ftrace_bug+0x288/0x2e8 (unreliable)
ftrace_modify_all_code+0x168/0x210
arch_ftrace_update_code+0x18/0x30
ftrace_run_update_code+0x44/0xc0
ftrace_startup+0xf8/0x1c0
register_ftrace_function+0x4c/0xc0
function_trace_init+0x80/0xb0
tracing_set_tracer+0x2a4/0x4f0
tracing_set_trace_write+0xd4/0x130
vfs_write+0xf0/0x330
ksys_write+0x84/0x140
system_call_exception+0x14c/0x230
system_call_common+0xf0/0x27c
To fix this when updating kernel memory PTEs using ptesync.
Fixes: f1cb8f9beba8 ("powerpc/64s/radix: avoid ptesync after set_pte and ptep_set_access_flags")
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Tidy up change log slightly]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210208032957.1232102-1-jniethe5@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 7de21e679e6a789f3729e8402bc440b623a28eae upstream.
A few archs like powerpc have different errno.h values for macros
EDEADLOCK and EDEADLK. In code including both libc and linux versions of
errno.h, this can result in multiple definitions of EDEADLOCK in the
include chain. Definitions to the same value (e.g. seen with mips) do
not raise warnings, but on powerpc there are redefinitions changing the
value, which raise warnings and errors (if using "-Werror").
Guard against these redefinitions to avoid build errors like the following,
first seen cross-compiling libbpf v5.8.9 for powerpc using GCC 8.4.0 with
musl 1.1.24:
In file included from ../../arch/powerpc/include/uapi/asm/errno.h:5,
from ../../include/linux/err.h:8,
from libbpf.c:29:
../../include/uapi/asm-generic/errno.h:40: error: "EDEADLOCK" redefined [-Werror]
#define EDEADLOCK EDEADLK
In file included from toolchain-powerpc_8540_gcc-8.4.0_musl/include/errno.h:10,
from libbpf.c:26:
toolchain-powerpc_8540_gcc-8.4.0_musl/include/bits/errno.h:58: note: this is the location of the previous definition
#define EDEADLOCK 58
cc1: all warnings being treated as errors
Cc: Stable <stable@vger.kernel.org>
Reported-by: Rosen Penev <rosenp@gmail.com>
Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200917135437.1238787-1-Tony.Ambardar@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 49c1d07fd04f54eb588c4a1dfcedc8d22c5ffd50 upstream.
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: 7fa95f9adaee ("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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1c4bce6753857dc409a0197342d18764e7f4b741 upstream.
Since commit 511157ab641e ("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 511157ab641e 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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code relies on constant folding of cpu_has_feature() based
on possible and always true values as defined per
CPU_FTRS_ALWAYS and CPU_FTRS_POSSIBLE.
Build failure is encountered with for instance
book3e_all_defconfig on kisskb in the AMDGPU driver which uses
cpu_has_feature(CPU_FTR_VSX_COMP) to decide whether calling
kernel_enable_vsx() or not.
The failure is due to cpu_has_feature() not being inlined with
that configuration with gcc 4.9.
In the same way as commit acdad8fb4a15 ("powerpc: Force inlining of
mmu_has_feature to fix build failure"), for inlining of
cpu_has_feature().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b231dfa040ce4cc37f702f5c3a595fdeabfe0462.1615378209.git.christophe.leroy@csgroup.eu
unrecoverable_exception() is called from interrupt handlers or
after an interrupt handler has failed.
Make it a standard function to avoid doubling the actions
performed on interrupt entry (e.g.: user time accounting).
Fixes: 3a96570ffceb ("powerpc: convert interrupt handlers to use wrappers")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ae96c59fa2cb7f24a8929c58cfa2c909cb8ff1f1.1615291471.git.christophe.leroy@csgroup.eu
Add stub instances of enable_kernel_vsx() and disable_kernel_vsx()
when CONFIG_VSX is not set, to avoid following build failure.
CC [M] drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dcn_calcs.o
In file included from ./drivers/gpu/drm/amd/amdgpu/../display/dc/dm_services_types.h:29,
from ./drivers/gpu/drm/amd/amdgpu/../display/dc/dm_services.h:37,
from drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dcn_calcs.c:27:
drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dcn_calcs.c: In function 'dcn_bw_apply_registry_override':
./drivers/gpu/drm/amd/amdgpu/../display/dc/os_types.h:64:3: error: implicit declaration of function 'enable_kernel_vsx'; did you mean 'enable_kernel_fp'? [-Werror=implicit-function-declaration]
64 | enable_kernel_vsx(); \
| ^~~~~~~~~~~~~~~~~
drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dcn_calcs.c:640:2: note: in expansion of macro 'DC_FP_START'
640 | DC_FP_START();
| ^~~~~~~~~~~
./drivers/gpu/drm/amd/amdgpu/../display/dc/os_types.h:75:3: error: implicit declaration of function 'disable_kernel_vsx'; did you mean 'disable_kernel_fp'? [-Werror=implicit-function-declaration]
75 | disable_kernel_vsx(); \
| ^~~~~~~~~~~~~~~~~~
drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dcn_calcs.c:676:2: note: in expansion of macro 'DC_FP_END'
676 | DC_FP_END();
| ^~~~~~~~~
cc1: some warnings being treated as errors
make[5]: *** [drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dcn_calcs.o] Error 1
This works because the caller is checking if VSX is available using
cpu_has_feature():
#define DC_FP_START() { \
if (cpu_has_feature(CPU_FTR_VSX_COMP)) { \
preempt_disable(); \
enable_kernel_vsx(); \
} else if (cpu_has_feature(CPU_FTR_ALTIVEC_COMP)) { \
preempt_disable(); \
enable_kernel_altivec(); \
} else if (!cpu_has_feature(CPU_FTR_FPU_UNAVAILABLE)) { \
preempt_disable(); \
enable_kernel_fp(); \
} \
When CONFIG_VSX is not selected, cpu_has_feature(CPU_FTR_VSX_COMP)
constant folds to 'false' so the call to enable_kernel_vsx() is
discarded and the build succeeds.
Fixes: 16a9dea110a6 ("amdgpu: Enable initial DCN support on POWER")
Cc: stable@vger.kernel.org # v5.6+
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Incorporate some discussion comments into the change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8d7d285a027e9d21f5ff7f850fa71a2655b0c4af.1615279170.git.christophe.leroy@csgroup.eu