Paul is no longer handling patches for kvmppc.
Instead we'll treat them as regular powerpc patches, taking them via the
powerpc tree, using the topic/ppc-kvm branch when necessary.
Also drop the web reference, it doesn't have any information
specifically relevant to powerpc KVM.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211027061646.540708-1-mpe@ellerman.id.au
Early exits from for_each_compatible_node() should decrement the
node reference counter. Reported by Coccinelle:
./arch/powerpc/platforms/44x/fsp2.c:206:1-25: WARNING: Function
"for_each_compatible_node" should have of_node_put() before return
around line 218.
Fixes: 7813043e1b ("powerpc/44x/fsp2: Add irq error handlers")
Signed-off-by: Bixuan Cui <cuibixuan@linux.alibaba.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1635406102-88719-1-git-send-email-cuibixuan@linux.alibaba.com
In dcr-low.S we use cmpli with three arguments, instead of four
arguments as defined in the ISA:
cmpli cr0,r3,1024
This appears to be a PPC440-ism, looking at the "PPC440x5 CPU Core
User’s Manual" it shows cmpli having no L field, but implied to be 0 due
to the core being 32-bit. It mentions that the ISA defines four
arguments and recommends using cmplwi.
It also corresponds to the old POWER instruction set, which had no L
field there, a reserved bit instead.
dcr-low.S is only built 32-bit, because it is only built when
DCR_NATIVE=y, which is only selected by 40x and 44x. Looking at the
generated code (with gcc/gas) we see cmplwi as expected.
Although gas is happy with the 3-argument version when building for
32-bit, the LLVM assembler is not and errors out with:
arch/powerpc/sysdev/dcr-low.S:27:10: error: invalid operand for instruction
cmpli 0,%r3,1024; ...
^
Switch to the cmplwi extended opcode, which avoids any confusion when
reading the ISA, fixes the issue with the LLVM assembler, and also means
the code could be built 64-bit in future (though that's very unlikely).
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
BugLink: https://github.com/ClangBuiltLinux/linux/issues/1419
Link: https://lore.kernel.org/r/20211014024424.528848-1-mpe@ellerman.id.au
Commit 112665286d ("KVM: PPC: Book3S HV: Context tracking exit guest
context before enabling irqs") moved guest_exit() into the interrupt
protected area to avoid wrong context warning (or worse). The problem is
that tick-based time accounting has not yet been updated at this point
(because it depends on the timer interrupt firing), so the guest time
gets incorrectly accounted to system time.
To fix the problem, follow the x86 fix in commit 1604571401 ("Defer
vtime accounting 'til after IRQ handling"), and allow host IRQs to run
before accounting the guest exit time.
In the case vtime accounting is enabled, this is not required because TB
is used directly for accounting.
Before this patch, with CONFIG_TICK_CPU_ACCOUNTING=y in the host and a
guest running a kernel compile, the 'guest' fields of /proc/stat are
stuck at zero. With the patch they can be observed increasing roughly as
expected.
Fixes: e233d54d4d ("KVM: booke: use __kvm_guest_exit")
Fixes: 112665286d ("KVM: PPC: Book3S HV: Context tracking exit guest context before enabling irqs")
Cc: stable@vger.kernel.org # 5.12+
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
[np: only required for tick accounting, add Book3E fix, tweak changelog]
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211027142150.3711582-1-npiggin@gmail.com
The mitigation-patching.sh script in the powerpc selftests toggles
all mitigations on and off simultaneously, revealing that rfi_flush
and stf_barrier cannot safely operate at the same time due to races
in updating the static key.
On some systems, the static key code throws a warning and the kernel
remains functional. On others, the kernel will hang or crash.
Fix this by slapping on a mutex.
Fixes: 13799748b9 ("powerpc/64: use interrupt restart table to speed up return from interrupt")
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Russell Currey <ruscur@russell.cc>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211027072410.40950-1-ruscur@russell.cc
Up to now mcu_gpiochip_remove() returns zero unconditionally. Make it
return void instead which makes it easier to see in the callers that
there is no error to handle.
Also the return value of i2c remove callbacks is ignored anyway.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211021105657.72572-1-u.kleine-koenig@pengutronix.de
Building tqm8541_defconfig results in:
arch/powerpc/mm/nohash/fsl_book3e.c: In function 'settlbcam':
arch/powerpc/mm/nohash/fsl_book3e.c:126:40: error: '_PAGE_BAP_SX' undeclared (first use in this function)
126 | TLBCAM[index].MAS3 |= (flags & _PAGE_BAP_SX) ? MAS3_SX : 0;
| ^~~~~~~~~~~~
arch/powerpc/mm/nohash/fsl_book3e.c:126:40: note: each undeclared identifier is reported only once for each function it appears in
make[3]: *** [scripts/Makefile.build:277: arch/powerpc/mm/nohash/fsl_book3e.o] Error 1
make[2]: *** [scripts/Makefile.build:540: arch/powerpc/mm/nohash] Error 2
make[1]: *** [scripts/Makefile.build:540: arch/powerpc/mm] Error 2
make: *** [Makefile:1868: arch/powerpc] Error 2
This is because _PAGE_BAP_SX is not defined when using 32 bits PTE.
Now that _PAGE_EXEC contains both _PAGE_BAP_SX and _PAGE_BAP_UX, it can be used instead.
Fixes: 01116e6e98 ("powerpc/fsl_booke: Take exec flag into account when setting TLBCAMs")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/91a0235e7f2a85308b84aa5b9efd8d022e2b899a.1635226743.git.christophe.leroy@csgroup.eu
set_memory_x() calls pte_mkexec() which sets _PAGE_EXEC.
set_memory_nx() calls pte_exprotec() which clears _PAGE_EXEC.
Book3e has 2 bits, UX and SX, which defines the exec rights
resp. for user (PR=1) and for kernel (PR=0).
_PAGE_EXEC is defined as UX only.
An executable kernel page is set with either _PAGE_KERNEL_RWX
or _PAGE_KERNEL_ROX, which both have SX set and UX cleared.
So set_memory_nx() call for an executable kernel page does
nothing because UX is already cleared.
And set_memory_x() on a non-executable kernel page makes it
executable for the user and keeps it non-executable for kernel.
Also, pte_exec() always returns 'false' on kernel pages, because
it checks _PAGE_EXEC which doesn't include SX, so for instance
the W+X check doesn't work.
To fix this:
- change tlb_low_64e.S to use _PAGE_BAP_UX instead of _PAGE_USER
- sets both UX and SX in _PAGE_EXEC so that pte_exec() returns
true whenever one of the two bits is set and pte_exprotect()
clears both bits.
- Define a book3e specific version of pte_mkexec() which sets
either SX or UX based on UR.
Fixes: 1f9ad21c3b ("powerpc/mm: Implement set_memory() routines")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c41100f9c144dc5b62e5a751b810190c6b5d42fd.1635226743.git.christophe.leroy@csgroup.eu
Commit 26973fa5ac ("powerpc/mm: use pte helpers in generic code")
changed those two functions to use pte helpers to determine which
bits to clear and which bits to set.
This change was based on the assumption that bits to be set/cleared
are always the same and can be determined by applying the pte
manipulation helpers on __pte(0).
But on platforms like book3e, the bits depend on whether the page
is a user page or not.
For the time being it more or less works because of _PAGE_EXEC being
used for user pages only and exec right being set at all time on
kernel page. But following patch will clean that and output of
pte_mkexec() will depend on the page being a user or kernel page.
Instead of trying to make an even more complicated helper where bits
would become dependent on the final pte value, come back to a more
static situation like before commit 26973fa5ac ("powerpc/mm: use
pte helpers in generic code"), by introducing an 8xx specific
version of __ptep_set_access_flags() and ptep_set_wrprotect().
Fixes: 26973fa5ac ("powerpc/mm: use pte helpers in generic code")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/922bdab3a220781bae2360ff3dd5adb7fe4d34f1.1635226743.git.christophe.leroy@csgroup.eu
Running program with bpf-to-bpf function calls results in data access
exception (0x300) with the below call trace:
bpf_int_jit_compile+0x238/0x750 (unreliable)
bpf_check+0x2008/0x2710
bpf_prog_load+0xb00/0x13a0
__sys_bpf+0x6f4/0x27c0
sys_bpf+0x2c/0x40
system_call_exception+0x164/0x330
system_call_vectored_common+0xe8/0x278
as bpf_int_jit_compile() tries writing to write protected JIT code
location during the extra pass.
Fix it by holding off write protection of JIT code until the extra
pass, where branch target addresses fixup happens.
Fixes: 62e3d4210a ("powerpc/bpf: Write protect JIT code")
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211025055649.114728-1-hbathini@linux.ibm.com
The EPOCHSECONDS environment variable was added in bash 5.0 (released
2019). Some distributions of the "stable" and "long-term" variety ship
older versions of bash than this, so swap to using the date command
instead.
"%s" was added to coreutils `date` in 1993 so we should be good, but who
knows, it is a GNU extension and not part of the POSIX spec for `date`.
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211025102436.19177-1-ruscur@russell.cc
The check_return_regs_valid() can cause a false positive if the return
regs are marked as norestart and they are an HSRR type interrupt,
because the low bit in the bottom of regs->trap causes interrupt type
matching to fail.
This can occcur for example on bare metal with a HV privileged doorbell
interrupt that causes a signal, but do_signal returns early because
get_signal() fails, and takes the "No signal to deliver" path. In this
case no signal was delivered so the return location is not changed so
return SRRs are not invalidated, yet set_trap_norestart is called, which
messes up the match. Building go-1.16.6 is known to reproduce this.
Fix it by using the TRAP() accessor which masks out the low bit.
Fixes: 6eaaf9de35 ("powerpc/64s/interrupt: Check and fix srr_valid without crashing")
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211026122531.3599918-1-npiggin@gmail.com
While trying to build a simple Image for ACADIA platform, I got the
following error:
WRAP arch/powerpc/boot/simpleImage.acadia
INFO: Uncompressed kernel (size 0x6ae7d0) overlaps the address of the wrapper(0x400000)
INFO: Fixing the link_address of wrapper to (0x700000)
powerpc64-linux-gnu-ld : mode d'émulation non reconnu : -T
Émulations prises en charge : elf64ppc elf32ppc elf32ppclinux elf32ppcsim elf64lppc elf32lppc elf32lppclinux elf32lppcsim
make[1]: *** [arch/powerpc/boot/Makefile:424 : arch/powerpc/boot/simpleImage.acadia] Erreur 1
make: *** [arch/powerpc/Makefile:285 : simpleImage.acadia] Erreur 2
Trying again with V=1 shows the following command
powerpc64-linux-gnu-ld -m -T arch/powerpc/boot/zImage.lds -Ttext 0x700000 --no-dynamic-linker -o arch/powerpc/boot/simpleImage.acadia -Map wrapper.map arch/powerpc/boot/fixed-head.o arch/powerpc/boot/simpleboot.o ./zImage.3278022.o arch/powerpc/boot/wrapper.a
The argument of '-m' is missing.
This is due to the wrapper script calling 'objdump -p vmlinux' and
looking for 'file format', whereas the output of objdump is:
vmlinux: format de fichier elf32-powerpc
En-tête de programme:
LOAD off 0x00010000 vaddr 0xc0000000 paddr 0x00000000 align 2**16
filesz 0x0069e1d4 memsz 0x006c128c flags rwx
NOTE off 0x0064591c vaddr 0xc063591c paddr 0x0063591c align 2**2
filesz 0x00000054 memsz 0x00000054 flags ---
Add LC_ALL=C at the beginning of the wrapper script in order to get the
output expected by the script:
vmlinux: file format elf32-powerpc
Program Header:
LOAD off 0x00010000 vaddr 0xc0000000 paddr 0x00000000 align 2**16
filesz 0x0069e1d4 memsz 0x006c128c flags rwx
NOTE off 0x0064591c vaddr 0xc063591c paddr 0x0063591c align 2**2
filesz 0x00000054 memsz 0x00000054 flags ---
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a9ff3bc98035f63b122c051f02dc47c7aed10430.1635256089.git.christophe.leroy@csgroup.eu
For 64-bit book3s the default should be 64K as that's what modern CPUs
are designed for.
The following defconfigs already set CONFIG_PPC_64K_PAGES:
cell_defconfig
pasemi_defconfig
powernv_defconfig
ppc64_defconfig
pseries_defconfig
skiroot_defconfig
The have the option removed from the defconfig, as it is now the
default.
The defconfigs that now need to set CONFIG_PPC_4K_PAGES to maintain
their existing behaviour are:
g5_defconfig
maple_defconfig
microwatt_defconfig
ps3_defconfig
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
BugLink: https://github.com/linuxppc/issues/issues/109
Link: https://lore.kernel.org/r/20211015001649.45591-1-joel@jms.id.au
This reverts commit 566af8cda3.
This caused some conflicts vs the audit tree, and the audit maintainers
would prefer we postpone this to the next merge window so we have more
time for testing.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
On VMs with NX encryption, compression, and/or RNG offload, these
capabilities are described by nodes in the ibm,platform-facilities device
tree hierarchy:
$ tree -d /sys/firmware/devicetree/base/ibm,platform-facilities/
/sys/firmware/devicetree/base/ibm,platform-facilities/
├── ibm,compression-v1
├── ibm,random-v1
└── ibm,sym-encryption-v1
3 directories
The acceleration functions that these nodes describe are not disrupted by
live migration, not even temporarily.
But the post-migration ibm,update-nodes sequence firmware always sends
"delete" messages for this hierarchy, followed by an "add" directive to
reconstruct it via ibm,configure-connector (log with debugging statements
enabled in mobility.c):
mobility: removing node /ibm,platform-facilities/ibm,random-v1:4294967285
mobility: removing node /ibm,platform-facilities/ibm,compression-v1:4294967284
mobility: removing node /ibm,platform-facilities/ibm,sym-encryption-v1:4294967283
mobility: removing node /ibm,platform-facilities:4294967286
...
mobility: added node /ibm,platform-facilities:4294967286
Note we receive a single "add" message for the entire hierarchy, and what
we receive from the ibm,configure-connector sequence is the top-level
platform-facilities node along with its three children. The debug message
simply reports the parent node and not the whole subtree.
Also, significantly, the nodes added are almost completely equivalent to
the ones removed; even phandles are unchanged. ibm,shared-interrupt-pool in
the leaf nodes is the only property I've observed to differ, and Linux does
not use that. So in practice, the sum of update messages Linux receives for
this hierarchy is equivalent to minor property updates.
We succeed in removing the original hierarchy from the device tree. But the
vio bus code is ignorant of this, and does not unbind or relinquish its
references. The leaf nodes, still reachable through sysfs, of course still
refer to the now-freed ibm,platform-facilities parent node, which makes
use-after-free possible:
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 3 PID: 1706 at lib/refcount.c:25 refcount_warn_saturate+0x164/0x1f0
refcount_warn_saturate+0x160/0x1f0 (unreliable)
kobject_get+0xf0/0x100
of_node_get+0x30/0x50
of_get_parent+0x50/0xb0
of_fwnode_get_parent+0x54/0x90
fwnode_count_parents+0x50/0x150
fwnode_full_name_string+0x30/0x110
device_node_string+0x49c/0x790
vsnprintf+0x1c0/0x4c0
sprintf+0x44/0x60
devspec_show+0x34/0x50
dev_attr_show+0x40/0xa0
sysfs_kf_seq_show+0xbc/0x200
kernfs_seq_show+0x44/0x60
seq_read_iter+0x2a4/0x740
kernfs_fop_read_iter+0x254/0x2e0
new_sync_read+0x120/0x190
vfs_read+0x1d0/0x240
Moreover, the "new" replacement subtree is not correctly added to the
device tree, resulting in ibm,platform-facilities parent node without the
appropriate leaf nodes, and broken symlinks in the sysfs device hierarchy:
$ tree -d /sys/firmware/devicetree/base/ibm,platform-facilities/
/sys/firmware/devicetree/base/ibm,platform-facilities/
0 directories
$ cd /sys/devices/vio ; find . -xtype l -exec file {} +
./ibm,sym-encryption-v1/of_node: broken symbolic link to
../../../firmware/devicetree/base/ibm,platform-facilities/ibm,sym-encryption-v1
./ibm,random-v1/of_node: broken symbolic link to
../../../firmware/devicetree/base/ibm,platform-facilities/ibm,random-v1
./ibm,compression-v1/of_node: broken symbolic link to
../../../firmware/devicetree/base/ibm,platform-facilities/ibm,compression-v1
This is because add_dt_node() -> dlpar_attach_node() attaches only the
parent node returned from configure-connector, ignoring any children. This
should be corrected for the general case, but fixing that won't help with
the stale OF node references, which is the more urgent problem.
One way to address that would be to make the drivers respond to node
removal notifications, so that node references can be dropped
appropriately. But this would likely force the drivers to disrupt active
clients for no useful purpose: equivalent nodes are immediately re-added.
And recall that the acceleration capabilities described by the nodes remain
available throughout the whole process.
The solution I believe to be robust for this situation is to convert
remove+add of a node with an unchanged phandle to an update of the node's
properties in the Linux device tree structure. That would involve changing
and adding a fair amount of code, and may take several iterations to land.
Until that can be realized we have a confirmed use-after-free and the
possibility of memory corruption. So add a limited workaround that
discriminates on the node type, ignoring adds and removes. This should be
amenable to backporting in the meantime.
Fixes: 410bccf978 ("powerpc/pseries: Partition migration in the kernel")
Cc: stable@vger.kernel.org
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211020194703.2613093-1-nathanl@linux.ibm.com
Long time ago we had a config item called STRICT_MM_TYPECHECKS
to build the kernel with pte_t defined as a structure in order
to perform additional build checks or build it with pte_t
defined as a simple type in order to get simpler generated code.
Commit 670eea9241 ("powerpc/mm: Always use STRICT_MM_TYPECHECKS")
made the struct based definition the only one, considering that the
generated code was similar in both cases.
That's right on ppc64 because the ABI is such that the content of a
struct having a single simple type element is passed as register,
but on ppc32 such a structure is passed via the stack like any
structure.
Simple test function:
pte_t test(pte_t pte)
{
return pte;
}
Before this patch we get
c00108ec <test>:
c00108ec: 81 24 00 00 lwz r9,0(r4)
c00108f0: 91 23 00 00 stw r9,0(r3)
c00108f4: 4e 80 00 20 blr
So, for PPC32, restore the simple type behaviour we got before
commit 670eea9241, but instead of adding a config option to
activate type check, do it when __CHECKER__ is set so that type
checking is performed by 'sparse' and provides feedback like:
arch/powerpc/mm/pgtable.c:466:16: warning: incorrect type in return expression (different base types)
arch/powerpc/mm/pgtable.c:466:16: expected unsigned long
arch/powerpc/mm/pgtable.c:466:16: got struct pte_t [usertype] x
With this patch we now get
c0010890 <test>:
c0010890: 4e 80 00 20 blr
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Define STRICT_MM_TYPECHECKS rather than repeating the condition]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c904599f33aaf6bb7ee2836a9ff8368509e0d78d.1631887042.git.christophe.leroy@csgroup.eu
CONFIG_STRICT_KERNEL_RWX should be set by default on every
architectures (See https://github.com/KSPP/linux/issues/4)
On PPC32 we have to find a compromise between performance and/or
memory wasting and selection of strict_kernel_rwx, because it implies
either smaller memory chunks or larger alignment between RO memory
and RW memory.
For instance the 8xx maps memory with 8M pages. So either the limit
between RO and RW must be 8M aligned or it falls back or 512k pages
which implies more pressure on the TLB.
book3s/32 maps memory with BATs as much as possible. BATS can have
any power-of-two size between 128k and 256M but we have only 4 to 8
BATs so the alignment must be good enough to allow efficient use of
the BATs and avoid falling back on standard page mapping which would
kill performance.
So let's go one step forward and make it the default but still allow
users to unset it when wanted.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/057c40164084bfc7d77c0b2ff78d95dbf6a2a21b.1632503622.git.christophe.leroy@csgroup.eu
In the old days, when we didn't have kernel userspace access
protection and had set_fs(), it was wise to use __get_user()
and friends to read kernel memory.
Nowadays, get_user() and put_user() are granting userspace access and
are exclusively for userspace access.
Convert single step emulation functions to user_access_begin() and
friends and use unsafe_get_user() and unsafe_put_user().
When addressing kernel addresses, there is no need to open userspace
access. And for book3s/32 it is particularly important to no try and
open userspace access on kernel address, because that would break the
content of kernel space segment registers. No guard has been put
against that risk in order to avoid degrading performance.
copy_from_kernel_nofault() and copy_to_kernel_nofault() should
be used but they are out-of-line functions which would degrade
performance. Those two functions are making use of
__get_kernel_nofault() and __put_kernel_nofault() macros.
Those two macros are just wrappers behind __get_user_size_goto() and
__put_user_size_goto().
unsafe_get_user() and unsafe_put_user() are also wrappers of
__get_user_size_goto() and __put_user_size_goto(). Use them to
access kernel space. That allows refactoring userspace and
kernelspace access.
Reported-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Depends-on: 4fe5cda9f8 ("powerpc/uaccess: Implement user_read_access_begin and user_write_access_begin")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/22831c9d17f948680a12c5292e7627288b15f713.1631817805.git.christophe.leroy@csgroup.eu
dcbz instruction shouldn't be used on non-cached memory. Using
it on non-cached memory can result in alignment exception and
implies a heavy handling.
Instead of silentely emulating the instruction and resulting in high
performance degradation, warn whenever an alignment exception is
taken in kernel mode due to dcbz, so that the user is made aware that
dcbz instruction has been used unexpectedly by the kernel.
Reported-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2e3acfe63d289c6fba366e16973c9ab8369e8b75.1631803922.git.christophe.leroy@csgroup.eu
Add support for out-of-line static calls on PPC32. This change
improve performance of calls to global function pointers by
using direct calls instead of indirect calls.
The trampoline is initialy populated with a 'blr' or branch to target,
followed by an unreachable long jump sequence.
In order to cater with parallele execution, the trampoline needs to
be updated in a way that ensures it remains consistent at all time.
This means we can't use the traditional lis/addi to load r12 with
the target address, otherwise there would be a window during which
the first instruction contains the upper part of the new target
address while the second instruction still contains the lower part of
the old target address. To avoid that the target address is stored
just after the 'bctr' and loaded from there with a single instruction.
Then, depending on the target distance, arch_static_call_transform()
will either replace the first instruction by a direct 'bl <target>' or
'nop' in order to have the trampoline fall through the long jump
sequence.
For the special case of __static_call_return0(), to avoid the risk of
a far branch, a version of it is inlined at the end of the trampoline.
Performancewise the long jump sequence is probably not better than
the indirect calls set by GCC when we don't use static calls, but
such calls are unlikely to be required on powerpc32: With most
configurations the kernel size is far below 32 Mbytes so only
modules may happen to be too far. And even modules are likely to
be close enough as they are allocated below the kernel core and
as close as possible of the kernel text.
static_call selftest is running successfully with this change.
With this patch, __do_irq() has the following sequence to trace
irq entries:
c0004a00 <__SCT__tp_func_irq_entry>:
c0004a00: 48 00 00 e0 b c0004ae0 <__traceiter_irq_entry>
c0004a04: 3d 80 c0 00 lis r12,-16384
c0004a08: 81 8c 4a 1c lwz r12,18972(r12)
c0004a0c: 7d 89 03 a6 mtctr r12
c0004a10: 4e 80 04 20 bctr
c0004a14: 38 60 00 00 li r3,0
c0004a18: 4e 80 00 20 blr
c0004a1c: 00 00 00 00 .long 0x0
...
c0005654 <__do_irq>:
...
c0005664: 7c 7f 1b 78 mr r31,r3
...
c00056a0: 81 22 00 00 lwz r9,0(r2)
c00056a4: 39 29 00 01 addi r9,r9,1
c00056a8: 91 22 00 00 stw r9,0(r2)
c00056ac: 3d 20 c0 af lis r9,-16209
c00056b0: 81 29 74 cc lwz r9,29900(r9)
c00056b4: 2c 09 00 00 cmpwi r9,0
c00056b8: 41 82 00 10 beq c00056c8 <__do_irq+0x74>
c00056bc: 80 69 00 04 lwz r3,4(r9)
c00056c0: 7f e4 fb 78 mr r4,r31
c00056c4: 4b ff f3 3d bl c0004a00 <__SCT__tp_func_irq_entry>
Before this patch, __do_irq() was doing the following to trace irq
entries:
c0005700 <__do_irq>:
...
c0005710: 7c 7e 1b 78 mr r30,r3
...
c000574c: 93 e1 00 0c stw r31,12(r1)
c0005750: 81 22 00 00 lwz r9,0(r2)
c0005754: 39 29 00 01 addi r9,r9,1
c0005758: 91 22 00 00 stw r9,0(r2)
c000575c: 3d 20 c0 af lis r9,-16209
c0005760: 83 e9 f4 cc lwz r31,-2868(r9)
c0005764: 2c 1f 00 00 cmpwi r31,0
c0005768: 41 82 00 24 beq c000578c <__do_irq+0x8c>
c000576c: 81 3f 00 00 lwz r9,0(r31)
c0005770: 80 7f 00 04 lwz r3,4(r31)
c0005774: 7d 29 03 a6 mtctr r9
c0005778: 7f c4 f3 78 mr r4,r30
c000577c: 4e 80 04 21 bctrl
c0005780: 85 3f 00 0c lwzu r9,12(r31)
c0005784: 2c 09 00 00 cmpwi r9,0
c0005788: 40 82 ff e4 bne c000576c <__do_irq+0x6c>
Behind the fact of now using a direct 'bl' instead of a
'load/mtctr/bctr' sequence, we can also see that we get one less
register on the stack.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/6ec2a7865ed6a5ec54ab46d026785bafe1d837ea.1630484892.git.christophe.leroy@csgroup.eu
ppc_md.iommu_save() is not set anymore by any platform after
commit c40785ad30 ("powerpc/dart: Use a cachable DART").
So iommu_save() has become a nop and can be removed.
ppc_md.show_percpuinfo() is not set anymore by any platform after
commit 4350147a81 ("[PATCH] ppc64: SMU based macs cpufreq support").
Last users of ppc_md.rtc_read_val() and ppc_md.rtc_write_val() were
removed by commit 0f03a43b8f ("[POWERPC] Remove todc code from
ARCH=powerpc")
Last user of kgdb_map_scc() was removed by commit 17ce452f7e ("kgdb,
powerpc: arch specific powerpc kgdb support").
ppc.machine_kexec_prepare() has not been used since
commit 8ee3e0d696 ("powerpc: Remove the main legacy iSerie platform
code"). This allows the removal of machine_kexec_prepare() and the
rename of default_machine_kexec_prepare() into machine_kexec_prepare()
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Daniel Axtens <dja@axtens.net>
[mpe: Drop prototype for default_machine_kexec_prepare() as noted by dja]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/24d4ca0ada683c9436a5f812a7aeb0a1362afa2b.1630398606.git.christophe.leroy@csgroup.eu
Commit d75d68cfef ("powerpc: Clean up obsolete code relating to
decrementer and timebase") made generic_suspend_enable_irqs() and
generic_suspend_disable_irqs() static.
Fold them into their only caller.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c3f9ec9950394ef939014f7934268e6ee30ca04f.1630398566.git.christophe.leroy@csgroup.eu
Commit e65e1fc2d2 ("[PATCH] syscall class hookup for all normal
targets") added generic support for AUDIT but that didn't include
support for bi-arch like powerpc.
Commit 4b58841149 ("audit: Add generic compat syscall support")
added generic support for bi-arch.
Convert powerpc to that bi-arch generic audit support.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a4b3951d1191d4183d92a07a6097566bde60d00a.1629812058.git.christophe.leroy@csgroup.eu
Instructions lmw/stmw are interesting for functions that are rarely
used and not in the cache, because only one instruction is to be
copied into the instruction cache instead of 19. However those
instruction are less performant than 19x raw lwz/stw as they require
synchronisation plus one additional cycle.
SAVE_NVGPRS / REST_NVGPRS are used in only a few places which are
mostly in interrupts entries/exits and in task switch so they are
likely already in the cache.
Using standard lwz improves null_syscall selftest by:
- 10 cycles on mpc832x.
- 2 cycles on mpc8xx.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/316c543b8906712c108985c8463eec09c8db577b.1629732542.git.christophe.leroy@csgroup.eu
Fixes build warnings:
Warning (unit_address_vs_reg): /memory: node has a reg or ranges property, but no unit name
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211013220532.24759-4-agust@denx.de
(!ptr && !ptr->foo) strikes again. :)
The expression (!ptr && !ptr->foo) is bogus and in case ptr is NULL,
it leads to a NULL pointer dereference: ptr->foo.
Fix this by converting && to ||
This issue was detected with the help of Coccinelle, and audited and
fixed manually.
Fixes: 1a0d0d5ed5 ("powerpc/vas: Add platform specific user window operations")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211015050345.GA1161918@embeddedor
Enable STRICT_KERNEL_RWX on fsl_booke.
For that, we need additional TLBCAMs dedicated to linear mapping,
based on the alignment of _sinittext.
By default, up to 768 Mbytes of memory are mapped.
It uses 3 TLBCAMs of size 256 Mbytes.
With a data alignment of 16, we need up to 9 TLBCAMs:
16/16/16/16/64/64/64/256/256
With a data alignment of 4, we need up to 12 TLBCAMs:
4/4/4/4/16/16/16/64/64/64/256/256
With a data alignment of 1, we need up to 15 TLBCAMs:
1/1/1/1/4/4/4/16/16/16/64/64/64/256/256
By default, set a 16 Mbytes alignment as a compromise between memory
usage and number of TLBCAMs. This can be adjusted manually when needed.
For the time being, it doens't work when the base is randomised.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/29f9e5d2bbbc83ae9ca879265426a6278bf4d5bb.1634292136.git.christophe.leroy@csgroup.eu
Reorganise TLBCAM allocation so that when STRICT_KERNEL_RWX is
enabled, TLBCAMs are allocated such that readonly memory uses
different TLBCAMs.
This results in an allocation looking like:
Memory CAM mapping: 4/4/4/1/1/1/1/16/16/16/64/64/64/256/256 Mb, residual: 256Mb
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8ca169bc288261a0e0558712f979023c3a960ebb.1634292136.git.christophe.leroy@csgroup.eu
Avoid switching to AS1 when reloading TLBCAM after init for
STRICT_KERNEL_RWX.
When we setup AS1 we expect the entire accessible memory to be mapped
through one entry, this is not the case anymore at the end of init.
We are not changing the size of TLBCAMs, only flags, so no need to
switch to AS1.
So change loadcam_multi() to not switch to AS1 when the given
temporary tlb entry in 0.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a9d517fbfbc940f56103c46b323f6eb8f4485571.1634292136.git.christophe.leroy@csgroup.eu
Don't force MAS3_SX and MAS3_UX at all time. Take into account the
exec flag.
While at it, fix a couple of closeby style problems (indent with space
and unnecessary parenthesis), it keeps more readability.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5467044e59f27f9fcf709b9661779e3ce5f784f6.1634292136.git.christophe.leroy@csgroup.eu
We have a myriad of CONFIG symbols around different variants
of BOOKEs, which would be worth tidying up one day.
But at least, make file names and CONFIG option match:
We have CONFIG_FSL_BOOKE and CONFIG_PPC_FSL_BOOK3E.
fsl_booke.c is selected by and only by CONFIG_PPC_FSL_BOOK3E.
So rename it fsl_book3e to reduce confusion.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5dc871db1f67739319bec11f049ca450da1c13a2.1634292136.git.christophe.leroy@csgroup.eu
fsl_booke and 44x are not able to map kernel linear memory with
pages, so they can't support DEBUG_PAGEALLOC and KFENCE, and
STRICT_KERNEL_RWX is also a problem for now.
Enable those only on book3s (both 32 and 64 except KFENCE), 8xx and 40x.
Fixes: 88df6e90fa ("[POWERPC] DEBUG_PAGEALLOC for 32-bit")
Fixes: 95902e6c88 ("powerpc/mm: Implement STRICT_KERNEL_RWX on PPC32")
Fixes: 90cbac0e99 ("powerpc: Enable KFENCE for PPC32")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d1ad9fdd9b27da3fdfa16510bb542ed51fa6e134.1634292136.git.christophe.leroy@csgroup.eu
Fix following coccicheck warning:
./arch/powerpc/kexec/file_load_64.c:698:1-22: WARNING: Function
for_each_node_by_type should have of_node_put() before goto
Early exits from for_each_node_by_type should decrement the
node reference counter.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211018015418.10182-1-wanjiabing@vivo.com
Fix following coccicheck warning:
./arch/powerpc/platforms/pseries/iommu.c:924:1-28: WARNING: Function
for_each_node_with_property should have of_node_put() before break
Early exits from for_each_node_with_property should decrement the
node reference counter.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Reviewed-by: Leonardo Bras <leobras.c@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211014075624.16344-1-wanjiabing@vivo.com
The page_alloc.c code will call into __kernel_map_pages() when
DEBUG_PAGEALLOC is configured and enabled.
As the implementation assumes hash, this should crash spectacularly if
not for a bit of luck in __kernel_map_pages(). In this function
linear_map_hash_count is always zero, the for loop exits without doing
any damage.
There are no other platforms that determine if they support
debug_pagealloc at runtime. Instead of adding code to mm/page_alloc.c to
do that, this change turns the map/unmap into a noop when in radix
mode and prints a warning once.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Reformat if per Christophe's suggestion]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211013213438.675095-1-joel@jms.id.au
.opd section contains function descriptors used to locate
functions in the kernel. If someone is able to modify a
function descriptor he will be able to run arbitrary
kernel function instead of another.
To avoid that, move .opd section inside read-only memory.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3cd40b682fb6f75bb40947b55ca0bac20cb3f995.1634136222.git.christophe.leroy@csgroup.eu
On power9 and earlier platforms, the default event used for cyles and
instructions is PM_CYC (0x0001e) and PM_INST_CMPL (0x00002)
respectively. These events use two programmable PMCs and by default will
count irrespective of the run latch state (idle state). But since they
use programmable PMCs, these events can lead to multiplexing with other
events, because there are only 4 programmable PMCs. Hence in power10,
performance monitoring unit (PMU) driver uses performance monitor
counter 5 (PMC5) and performance monitor counter6 (PMC6) for counting
instructions and cycles.
Currently on power10, the event used for cycles is PM_RUN_CYC (0x600F4)
and instructions uses PM_RUN_INST_CMPL (0x500fa). But counting of these
events in idle state is controlled by the CC56RUN bit setting in Monitor
Mode Control Register0 (MMCR0). If the CC56RUN bit is zero, PMC5/6 will
not count when CTRL[RUN] (run latch) is zero. This could lead to missing
some counts if a thread is in idle state during system wide profiling.
To fix it, set the CC56RUN bit in MMCR0 for power10, which makes PMC5
and PMC6 count instructions and cycles regardless of the run latch
state. Since this change make PMC5/6 count as PM_INST_CMPL/PM_CYC,
rename the event code 0x600f4 as PM_CYC instead of PM_RUN_CYC and event
code 0x500fa as PM_INST_CMPL instead of PM_RUN_INST_CMPL. The changes
are only for PMC5/6 event codes and will not affect the behaviour of
PM_RUN_CYC/PM_RUN_INST_CMPL if progammed in other PMC's.
Fixes: a64e697cef ("powerpc/perf: power10 Performance Monitoring support")
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.cm>
Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
[mpe: Tweak change log wording for style and consistency]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211007075121.28497-1-atrajeev@linux.vnet.ibm.com
We fix the following warnings when building kernel with W=1:
arch/powerpc/kernel/eeh.c:598: warning: Function parameter or member 'function' not described in 'eeh_pci_enable'
arch/powerpc/kernel/eeh.c:774: warning: Function parameter or member 'edev' not described in 'eeh_set_dev_freset'
arch/powerpc/kernel/eeh.c:774: warning: expecting prototype for eeh_set_pe_freset(). Prototype was for eeh_set_dev_freset() instead
arch/powerpc/kernel/eeh.c:814: warning: Function parameter or member 'include_passed' not described in 'eeh_pe_reset_full'
arch/powerpc/kernel/eeh.c:944: warning: Function parameter or member 'ops' not described in 'eeh_init'
arch/powerpc/kernel/eeh.c:1451: warning: Function parameter or member 'include_passed' not described in 'eeh_pe_reset'
arch/powerpc/kernel/eeh.c:1526: warning: Function parameter or member 'func' not described in 'eeh_pe_inject_err'
arch/powerpc/kernel/eeh.c:1526: warning: Excess function parameter 'function' described in 'eeh_pe_inject_err'
Signed-off-by: Kai Song <songkai01@inspur.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211009041630.4135-1-songkai01@inspur.com
CONFIG_PPC64_BOOT_WRAPPER is selected by CPU_LITTLE_ENDIAN which is
used to compile support for other platforms such as Microwatt. There
is no need for OPAL calls on these.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211011070356.99952-1-clg@kaod.org
max_mapnr is used by virt_addr_valid() to check if a linear
address is valid.
It must only include lowmem PFNs, like other architectures.
Problem detected on a system with 1G mem (Only 768M are mapped), with
CONFIG_DEBUG_VIRTUAL and CONFIG_TEST_DEBUG_VIRTUAL, it didn't report
virt_to_phys(VMALLOC_START), VMALLOC_START being 0xf1000000.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/77d99037782ac4b3c3b0124fc4ae80ce7b760b05.1634035228.git.christophe.leroy@csgroup.eu
The HPTE B field is a 2-bit field with values 0b10 and 0b11 reserved.
This field is also taken from the HPTE and used when KVM executes
TLBIEs to set the B field of those instructions.
Disallow the guest setting B to a reserved value with H_ENTER by
rejecting it. This is the same approach already taken for rejecting
reserved (unsupported) LLP values. This prevents the guest from being
able to induce the host to execute TLBIE with reserved values, which
is not known to be a problem with current processors but in theory it
could prevent the TLBIE from working correctly in a future processor.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211004145749.1331331-1-npiggin@gmail.com