Christophe Leroy [Thu, 21 May 2020 16:55:53 +0000 (16:55 +0000)]
powerpc/40x: Rework 40x PTE access and TLB miss
Commit 1bc54c03117b ("powerpc: rework 4xx PTE access and TLB miss")
reworked 44x PTE access to avoid atomic pte updates, and
left 8xx, 40x and fsl booke with atomic pte updates.
Commit 6cfd8990e27d ("powerpc: rework FSL Book-E PTE access and TLB
miss") removed atomic pte updates on fsl booke.
It went away on 8xx with commit ddfc20a3b9ae ("powerpc/8xx: Remove
PTE_ATOMIC_UPDATES").
40x is the last platform setting PTE_ATOMIC_UPDATES.
Rework PTE access and TLB miss to remove PTE_ATOMIC_UPDATES for 40x:
- Always handle DSI as a fault.
- Bail out of TLB miss handler when CONFIG_SWAP is set and
_PAGE_ACCESSED is not set.
- Bail out of ITLB miss handler when _PAGE_EXEC is not set.
- Only set WR bit when both _PAGE_RW and _PAGE_DIRTY are set.
- Remove _PAGE_HWWRITE
- Don't require PTE_ATOMIC_UPDATES anymore
Michal Simek [Mon, 30 Mar 2020 13:32:16 +0000 (15:32 +0200)]
sound: ac97: Remove sound driver for ancient platform
Xilinx PowerPC platforms are no longer supported and none is really testing
these platforms that's why remove them. If someone has any issue with it
these patches can be reverted.
Michal Simek [Thu, 21 May 2020 16:55:52 +0000 (16:55 +0000)]
powerpc: Remove Xilinx PPC405/PPC440 support
The latest Xilinx design tools called ISE and EDK has been released in
October 2013. New tool doesn't support any PPC405/PPC440 new designs.
These platforms are no longer supported and tested.
PowerPC 405/440 port is orphan from 2013 by
commit cdeb89943bfc ("MAINTAINERS: Fix incorrect status tag") and
commit 19624236cce1 ("MAINTAINERS: Update Grant's email address and maintainership")
that's why it is time to remove the support fot these platforms.
Nicholas Piggin [Mon, 4 May 2020 12:29:07 +0000 (22:29 +1000)]
powerpc/64s/radix: Don't prefetch DAR in update_mmu_cache
The idea behind this prefetch was to kick off a page table walk before
returning from the fault, getting some pipelining advantage.
But this never showed up any noticable performance advantage, and in
fact with KUAP the prefetches are actually blocked and cause some
kind of micro-architectural fault. Removing this improves page fault
microbenchmark performance by about 9%.
This causes a build error with CONFIG_WALNUT because kb_cs and kb_data
were removed in commit 917f0af9e5a9 ("powerpc: Remove arch/ppc and
include/asm-ppc").
ld.lld: error: undefined symbol: kb_cs
> referenced by i8042-ppcio.h:28 (drivers/input/serio/i8042-ppcio.h:28)
> input/serio/i8042.o:(__i8042_command) in archive drivers/built-in.a
> referenced by i8042-ppcio.h:28 (drivers/input/serio/i8042-ppcio.h:28)
> input/serio/i8042.o:(__i8042_command) in archive drivers/built-in.a
> referenced by i8042-ppcio.h:28 (drivers/input/serio/i8042-ppcio.h:28)
> input/serio/i8042.o:(__i8042_command) in archive drivers/built-in.a
ld.lld: error: undefined symbol: kb_data
> referenced by i8042.c:309 (drivers/input/serio/i8042.c:309)
> input/serio/i8042.o:(__i8042_command) in archive drivers/built-in.a
> referenced by i8042-ppcio.h:33 (drivers/input/serio/i8042-ppcio.h:33)
> input/serio/i8042.o:(__i8042_command) in archive drivers/built-in.a
> referenced by i8042.c:319 (drivers/input/serio/i8042.c:319)
> input/serio/i8042.o:(__i8042_command) in archive drivers/built-in.a
> referenced 15 more times
Presumably since nobody has noticed this for the last 12 years, there is
not anyone actually trying to use this driver so we can just remove this
special walnut code and use the generic header so it builds for all
configurations.
Fixes: 917f0af9e5a9 ("powerpc: Remove arch/ppc and include/asm-ppc") Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Link: https://lore.kernel.org/r/20200518181043.3363953-1-natechancellor@gmail.com
powerpc/xive: Do not expose a debugfs file when XIVE is disabled
The XIVE interrupt mode can be disabled with the "xive=off" kernel
parameter, in which case there is nothing to present to the user in the
associated /sys/kernel/debug/powerpc/xive file.
Fixes: 930914b7d528 ("powerpc/xive: Add a debugfs file to dump internal XIVE state") Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200429075122.1216388-4-clg@kaod.org
powerpc/xive: Clear the page tables for the ESB IO mapping
Commit 1ca3dec2b2df ("powerpc/xive: Prevent page fault issues in the
machine crash handler") fixed an issue in the FW assisted dump of
machines using hash MMU and the XIVE interrupt mode under the POWER
hypervisor. It forced the mapping of the ESB page of interrupts being
mapped in the Linux IRQ number space to make sure the 'crash kexec'
sequence worked during such an event. But it didn't handle the
un-mapping.
This mapping is now blocking the removal of a passthrough IO adapter
under the POWER hypervisor because it expects the guest OS to have
cleared all page table entries related to the adapter. If some are
still present, the RTAS call which isolates the PCI slot returns error
9001 "valid outstanding translations".
Remove these mapping in the IRQ data cleanup routine.
Under KVM, this cleanup is not required because the ESB pages for the
adapter interrupts are un-mapped from the guest by the hypervisor in
the KVM XIVE native device. This is now redundant but it's harmless.
Fixes: 1ca3dec2b2df ("powerpc/xive: Prevent page fault issues in the machine crash handler") Cc: stable@vger.kernel.org # v5.5+ Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200429075122.1216388-2-clg@kaod.org
Michael Ellerman [Tue, 26 May 2020 07:26:30 +0000 (17:26 +1000)]
powerpc: Add ppc_inst_as_u64()
The code patching code wants to get the value of a struct ppc_inst as
a u64 when the instruction is prefixed, so we can pass the u64 down to
__put_user_asm() and write it with a single store.
The optprobes code wants to load a struct ppc_inst as an immediate
into a register so it is useful to have it as a u64 to use the
existing helper function.
Currently this is a bit awkward because the value differs based on the
CPU endianness, so add a helper to do the conversion.
This fixes the usage in arch_prepare_optimized_kprobe() which was
previously incorrect on big endian.
Michael Ellerman [Fri, 22 May 2020 13:33:18 +0000 (23:33 +1000)]
powerpc: Add ppc_inst_next()
In a few places we want to calculate the address of the next
instruction. Previously that was simple, we just added 4 bytes, or if
using a u32 * we incremented that pointer by 1.
But prefixed instructions make it more complicated, we need to advance
by either 4 or 8 bytes depending on the actual instruction. We also
can't do pointer arithmetic using struct ppc_inst, because it is
always 8 bytes in size on 64-bit, even though we might only need to
advance by 4 bytes.
So add a ppc_inst_next() helper which calculates the location of the
next instruction, if the given instruction was located at the given
address. Note the instruction doesn't need to actually be at the
address in memory.
Although it would seem natural for the value to be passed by value,
that makes it too easy to write a loop that will read off the end of a
page, eg:
for (; src < end; src = ppc_inst_next(src, *src),
dest = ppc_inst_next(dest, *dest))
As noticed by Christophe and Jordan, if end is the exact end of a
page, and the next page is not mapped, this will fault, because *dest
will read 8 bytes, 4 bytes into the next page.
So value is passed by reference, so the helper can be careful to use
ppc_inst_read() on it.
Michael Ellerman [Tue, 26 May 2020 12:56:03 +0000 (22:56 +1000)]
Merge branch 'fixes' into next
Merge our fixes branch from this cycle. It contains several important
fixes we need in next for testing purposes, and also some that will
conflict with upcoming changes.
Michael Ellerman [Tue, 26 May 2020 12:54:27 +0000 (22:54 +1000)]
Merge "Use hugepages to map kernel mem on 8xx" into next
Merge Christophe's large series to use huge pages for the linear
mapping on 8xx.
From his cover letter:
The main purpose of this big series is to:
- reorganise huge page handling to avoid using mm_slices.
- use huge pages to map kernel memory on the 8xx.
The 8xx supports 4 page sizes: 4k, 16k, 512k and 8M.
It uses 2 Level page tables, PGD having 1024 entries, each entry
covering 4M address space. Then each page table has 1024 entries.
At the time being, page sizes are managed in PGD entries, implying
the use of mm_slices as it can't mix several pages of the same size
in one page table.
The first purpose of this series is to reorganise things so that
standard page tables can also handle 512k pages. This is done by
adding a new _PAGE_HUGE flag which will be copied into the Level 1
entry in the TLB miss handler. That done, we have 2 types of pages:
- PGD entries to regular page tables handling 4k/16k and 512k pages
- PGD entries to hugepd tables handling 8M pages.
There is no need to mix 8M pages with other sizes, because a 8M page
will use more than what a single PGD covers.
Then comes the second purpose of this series. At the time being, the
8xx has implemented special handling in the TLB miss handlers in order
to transparently map kernel linear address space and the IMMR using
huge pages by building the TLB entries in assembly at the time of the
exception.
As mm_slices is only for user space pages, and also because it would
anyway not be convenient to slice kernel address space, it was not
possible to use huge pages for kernel address space. But after step
one of the series, it is now more flexible to use huge pages.
This series drop all assembly 'just in time' handling of huge pages
and use huge pages in page tables instead.
Once the above is done, then comes icing on the cake:
- Use huge pages for KASAN shadow mapping
- Allow pinned TLBs with strict kernel rwx
- Allow pinned TLBs with debug pagealloc
Then, last but not least, those modifications for the 8xx allows the
following improvement on book3s/32:
- Mapping KASAN shadow with BATs
- Allowing BATs with debug pagealloc
All this allows to considerably simplify TLB miss handlers and associated
initialisation. The overhead of reading page tables is negligible
compared to the reduction of the miss handlers.
While we were at touching pte_update(), some cleanup was done
there too.
Tested widely on 8xx and 832x. Boot tested on QEMU MAC99.
Christophe Leroy [Tue, 19 May 2020 05:49:28 +0000 (05:49 +0000)]
powerpc/32s: Allow mapping with BATs with DEBUG_PAGEALLOC
DEBUG_PAGEALLOC only manages RW data.
Text and RO data can still be mapped with BATs.
In order to map with BATs, also enforce data alignment. Set
by default to 256M which is a good compromise for keeping
enough BATs for also KASAN and IMMR.
Christophe Leroy [Tue, 19 May 2020 05:49:26 +0000 (05:49 +0000)]
powerpc/8xx: Allow large TLBs with DEBUG_PAGEALLOC
DEBUG_PAGEALLOC only manages RW data.
Text and RO data can still be mapped with hugepages and pinned TLB.
In order to map with hugepages, also enforce a 512kB data alignment
minimum. That's a trade-off between size of speed, taking into
account that DEBUG_PAGEALLOC is a debug option. Anyway the alignment
is still tunable.
We also allow tuning of alignment for book3s to limit the complexity
of the test in Kconfig that will anyway disappear in the following
patches once DEBUG_PAGEALLOC is handled together with BATs.
Christophe Leroy [Tue, 19 May 2020 05:49:25 +0000 (05:49 +0000)]
powerpc/8xx: Allow STRICT_KERNEL_RwX with pinned TLB
Pinned TLB are 8M. Now that there is no strict boundary anymore
between text and RO data, it is possible to use 8M pinned executable
TLB that covers both text and RO data.
When PIN_TLB_DATA or PIN_TLB_TEXT is selected, enforce 8M RW data
alignment and allow STRICT_KERNEL_RWX.
Christophe Leroy [Tue, 19 May 2020 05:49:22 +0000 (05:49 +0000)]
powerpc/8xx: Add a function to early map kernel via huge pages
Add a function to early map kernel memory using huge pages.
For 512k pages, just use standard page table and map in using 512k
pages.
For 8M pages, create a hugepd table and populate the two PGD
entries with it.
This function can only be used to create page tables at startup. Once
the regular SLAB allocation functions replace memblock functions,
this function cannot allocate new pages anymore. However it can still
update existing mappings with new protections.
hugepd_none() macro is moved into asm/hugetlb.h to be usable outside
of mm/hugetlbpage.c
Now that linear and IMMR dedicated TLB handling is gone, kernel
boundary address comparison is similar in ITLB miss handler and
in DTLB miss handler.
Create a macro named compare_to_kernel_boundary.
When TASK_SIZE is strictly below 0x80000000 and PAGE_OFFSET is
above 0x80000000, it is enough to compare to 0x8000000, and this
can be done with a single instruction.
Using not. instruction, we get to use 'blt' conditional branch as
when doing a regular comparison:
0x00000000 <= addr <= 0x7fffffff ==>
0xffffffff >= NOT(addr) >= 0x80000000
The above test corresponds to a 'blt'
Otherwise, do a regular comparison using two instructions.
Christophe Leroy [Tue, 19 May 2020 05:49:16 +0000 (05:49 +0000)]
powerpc/8xx: Drop special handling of Linear and IMMR mappings in I/D TLB handlers
Up to now, linear and IMMR mappings are managed via huge TLB entries
through specific code directly in TLB miss handlers. This implies
some patching of the TLB miss handlers at startup, and a lot of
dedicated code.
Remove all this specific dedicated code.
For now we are back to normal handling via standard 4k pages. In the
next patches, linear memory mapping and IMMR mapping will be managed
through huge pages.
Christophe Leroy [Tue, 19 May 2020 05:49:15 +0000 (05:49 +0000)]
powerpc/8xx: Always pin TLBs at startup.
At startup, map 32 Mbytes of memory through 4 pages of 8M,
and PIN them inconditionnaly. They need to be pinned because
KASAN is using page tables early and the TLBs might be
dynamically replaced otherwise.
Remove RSV4I flag after installing mappings unless
CONFIG_PIN_TLB_XXXX is selected.
Christophe Leroy [Tue, 19 May 2020 05:49:13 +0000 (05:49 +0000)]
powerpc/8xx: Add function to set pinned TLBs
Pinned TLBs cannot be modified when the MMU is enabled.
Create a function to rewrite the pinned TLB entries with MMU off.
To set pinned TLB, we have to turn off MMU, disable pinning,
do a TLB flush (Either with tlbie and tlbia) then reprogam
the TLB entries, enable pinning and turn on MMU.
If using tlbie, it cleared entries in both instruction and data
TLB regardless whether pinning is disabled or not.
If using tlbia, it clears all entries of the TLB which has
disabled pinning.
To make it easy, just clear all entries in both TLBs, and
reprogram them.
The function takes two arguments, the top of the memory to
consider and whether data is RO under _sinittext.
When DEBUG_PAGEALLOC is set, the top is the end of kernel rodata.
Otherwise, that's the top of physical RAM.
Everything below _sinittext is set RX, over _sinittext that's RW.
Christophe Leroy [Tue, 19 May 2020 05:49:09 +0000 (05:49 +0000)]
powerpc/8xx: Manage 512k huge pages as standard pages.
At the time being, 512k huge pages are handled through hugepd page
tables. The PMD entry is flagged as a hugepd pointer and it
means that only 512k hugepages can be managed in that 4M block.
However, the hugepd table has the same size as a normal page
table, and 512k entries can therefore be nested with normal pages.
On the 8xx, TLB loading is performed by software and allthough the
page tables are organised to match the L1 and L2 level defined by
the HW, all TLB entries have both L1 and L2 independent entries.
It means that even if two TLB entries are associated with the same
PMD entry, they can be loaded with different values in L1 part.
The L1 entry contains the page size (PS field):
- 00 for 4k and 16 pages
- 01 for 512k pages
- 11 for 8M pages
By adding a flag for hugepages in the PTE (_PAGE_HUGE) and copying it
into the lower bit of PS, we can then manage 512k pages with normal
page tables:
- PMD entry has PS=11 for 8M pages
- PMD entry has PS=00 for other pages.
As a PMD entry covers 4M areas, a PMD will either point to a hugepd
table having a single entry to an 8M page, or the PMD will point to
a standard page table which will have either entries to 4k or 16k or
512k pages. For 512k pages, as the L1 entry will not know it is a
512k page before the PTE is read, there will be 128 entries in the
PTE as if it was 4k pages. But when loading the TLB, it will be
flagged as a 512k page.
Note that we can't use pmd_ptr() in asm/nohash/32/pgtable.h because
it is not defined yet.
In ITLB miss, we keep the possibility to opt it out as when kernel
text is pinned and no user hugepages are used, we can save several
instruction by not using r11.
In DTLB miss, that's just one instruction so it's not worth bothering
with it.
Christophe Leroy [Tue, 19 May 2020 05:49:08 +0000 (05:49 +0000)]
powerpc/8xx: Prepare handlers for _PAGE_HUGE for 512k pages.
Prepare ITLB handler to handle _PAGE_HUGE when CONFIG_HUGETLBFS
is enabled. This means that the L1 entry has to be kept in r11
until L2 entry is read, in order to insert _PAGE_HUGE into it.
Also move pgd_offset helpers before pte_update() as they
will be needed there in next patch.
Christophe Leroy [Tue, 19 May 2020 05:49:06 +0000 (05:49 +0000)]
powerpc/mm: Reduce hugepd size for 8M hugepages on 8xx
Commit 55c8fc3f4930 ("powerpc/8xx: reintroduce 16K pages with HW
assistance") redefined pte_t as a struct of 4 pte_basic_t, because
in 16K pages mode there are four identical entries in the page table.
But hugepd entries for 8M pages require only one entry of size
pte_basic_t. So there is no point in creating a cache for 4 entries
page tables.
Calculate PTE_T_ORDER using the size of pte_basic_t instead of pte_t.
Define specific huge_pte helpers (set_huge_pte_at(), huge_pte_clear(),
huge_ptep_set_wrprotect()) to write the pte in a single entry instead
of using set_pte_at() which writes 4 identical entries in 16k pages
mode. Also make sure that __ptep_set_access_flags() properly handle
the huge_pte case.
Define set_pte_filter() inline otherwise GCC doesn't inline it anymore
because it is now used twice, and that gives a pretty suboptimal code
because of pte_t being a struct of 4 entries.
Those functions are also used for 512k pages which only require one
entry as well allthough replicating it four times was harmless as 512k
pages entries are spread every 128 bytes in the table.
Christophe Leroy [Tue, 19 May 2020 05:48:58 +0000 (05:48 +0000)]
powerpc/mm: Allocate static page tables for fixmap
Allocate static page tables for the fixmap area. This allows
setting mappings through page tables before memblock is ready.
That's needed to use early_ioremap() early and to use standard
page mappings with fixmap.
Christophe Leroy [Tue, 19 May 2020 05:48:55 +0000 (05:48 +0000)]
powerpc/ptdump: Handle hugepd at PGD level
The 8xx is about to map kernel linear space and IMMR using huge
pages.
In order to display those pages properly, ptdump needs to handle
hugepd tables at PGD level.
For the time being do it only at PGD level. Further patches may
add handling of hugepd tables at lower level for other platforms
when needed in the future.
Michael Ellerman [Tue, 26 May 2020 06:18:08 +0000 (16:18 +1000)]
powerpc/64s: Fix restore of NV GPRs after facility unavailable exception
Commit 702f09805222 ("powerpc/64s/exception: Remove lite interrupt
return") changed the interrupt return path to not restore non-volatile
registers by default, and explicitly restore them in paths where it is
required.
But it missed that the facility unavailable exception can sometimes
modify user registers, ie. when it does emulation of move from DSCR.
This is seen as a failure of the dscr_sysfs_thread_test:
test: dscr_sysfs_thread_test
[cpu 0] User DSCR should be 1 but is 0
failure: dscr_sysfs_thread_test
So restore non-volatile GPRs after facility unavailable exceptions.
Currently the hypervisor facility unavailable exception is also wired
up to call facility_unavailable_exception().
In practice we should never take a hypervisor facility unavailable
exception for the DSCR. On older bare metal systems we set HFSCR_DSCR
unconditionally in __init_HFSCR, or on newer systems it should be
enabled via the "data-stream-control-register" device tree CPU
feature.
Even if it's not, since commit f3c99f97a3cd ("KVM: PPC: Book3S HV:
Don't access HFSCR, LPIDR or LPCR when running nested"), the KVM code
has unconditionally set HFSCR_DSCR when running guests.
So we should only get a hypervisor facility unavailable for the DSCR
if skiboot has disabled the "data-stream-control-register" feature,
and we are somehow in guest context but not via KVM.
Given all that, it should be unnecessary to add a restore of
non-volatile GPRs after the hypervisor facility exception, because we
never expect to hit that path. But equally we may as well add the
restore, because we never expect to hit that path, and if we ever did,
at least we would correctly restore the registers to their post
emulation state.
In future we can split the non-HV and HV facility unavailable handling
so that there is no emulation in the HV handler, and then remove the
restore for the HV case.
Michael Ellerman [Wed, 20 May 2020 13:36:05 +0000 (23:36 +1000)]
powerpc/64s: Disable STRICT_KERNEL_RWX
Several strange crashes have been eventually traced back to
STRICT_KERNEL_RWX and its interaction with code patching.
Various paths in our ftrace, kprobes and other patching code need to
be hardened against patching failures, otherwise we can end up running
with partially/incorrectly patched ftrace paths, kprobes or jump
labels, which can then cause strange crashes.
Although fixes for those are in development, they're not -rc material.
There also seem to be problems with the underlying strict RWX logic,
which needs further debugging.
So for now disable STRICT_KERNEL_RWX on 64-bit to prevent people from
enabling the option and tripping over the bugs.
Christophe Leroy [Tue, 19 May 2020 05:48:48 +0000 (05:48 +0000)]
powerpc/kasan: Declare kasan_init_region() weak
In order to alloc sub-arches to alloc KASAN regions using optimised
methods (Huge pages on 8xx, BATs on BOOK3S, ...), declare
kasan_init_region() weak.
Also make kasan_init_shadow_page_tables() accessible from outside,
so that it can be called from the specific kasan_init_region()
functions if needed.
And populate remaining KASAN address space only once performed
the region mapping, to allow 8xx to allocate hugepd instead of
standard page tables for mapping via 8M hugepages.
Christophe Leroy [Tue, 19 May 2020 05:48:47 +0000 (05:48 +0000)]
powerpc/kasan: Refactor update of early shadow mappings
kasan_remap_early_shadow_ro() and kasan_unmap_early_shadow_vmalloc()
are both updating the early shadow mapping: the first one sets
the mapping read-only while the other clears the mapping.
Doing kasan pages allocation in MMU_init is too early, kernel doesn't
have access yet to the entire memory space and memblock_alloc() fails
when the kernel is a bit big.
Christophe Leroy [Tue, 19 May 2020 05:48:44 +0000 (05:48 +0000)]
powerpc/kasan: Fix issues by lowering KASAN_SHADOW_END
At the time being, KASAN_SHADOW_END is 0x100000000, which
is 0 in 32 bits representation.
This leads to a couple of issues:
- kasan_remap_early_shadow_ro() does nothing because the comparison
k_cur < k_end is always false.
- In ptdump, address comparison for markers display fails and the
marker's name is printed at the start of the KASAN area instead of
being printed at the end.
However, there is no need to shadow the KASAN shadow area itself,
so the KASAN shadow area can stop shadowing memory at the start
of itself.
With a PAGE_OFFSET set to 0xc0000000, KASAN shadow area is then going
from 0xf8000000 to 0xff000000.
Nicholas Piggin [Mon, 11 May 2020 12:58:24 +0000 (22:58 +1000)]
powerpc/64s/hash: Add stress_slb kernel boot option to increase SLB faults
This option increases the number of SLB misses by limiting the number
of kernel SLB entries, and increased flushing of cached lookaside
information. This helps stress test difficult to hit paths in the
kernel.
Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Relocate the code into arch/powerpc/mm, s/torture/stress/] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200511125825.3081305-1-mpe@ellerman.id.au
Fix it by converting pud_index() and friends to static inline
functions.
UBSAN: shift-out-of-bounds in arch/powerpc/mm/ptdump/ptdump.c:282:15
shift exponent 34 is too large for 32-bit type 'int'
CPU: 6 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc4-next-20200303+ #13
Call Trace:
dump_stack+0xf4/0x164 (unreliable)
ubsan_epilogue+0x18/0x78
__ubsan_handle_shift_out_of_bounds+0x160/0x21c
walk_pagetables+0x2cc/0x700
walk_pud at arch/powerpc/mm/ptdump/ptdump.c:282
(inlined by) walk_pagetables at arch/powerpc/mm/ptdump/ptdump.c:311
ptdump_check_wx+0x8c/0xf0
mark_rodata_ro+0x48/0x80
kernel_init+0x74/0x194
ret_from_kernel_thread+0x5c/0x74
Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Link: https://lore.kernel.org/r/20200306044852.3236-1-cai@lca.pw
Nicholas Piggin [Wed, 29 Apr 2020 07:02:47 +0000 (17:02 +1000)]
powerpc/64s: Fix early_init_mmu section mismatch
Christian reports:
MODPOST vmlinux.o
WARNING: modpost: vmlinux.o(.text.unlikely+0x1a0): Section mismatch in
reference from the function .early_init_mmu() to the function
.init.text:.radix__early_init_mmu()
The function .early_init_mmu() references
the function __init .radix__early_init_mmu().
This is often because .early_init_mmu lacks a __init
annotation or the annotation of .radix__early_init_mmu is wrong.
WARNING: modpost: vmlinux.o(.text.unlikely+0x1ac): Section mismatch in
reference from the function .early_init_mmu() to the function
.init.text:.hash__early_init_mmu()
The function .early_init_mmu() references
the function __init .hash__early_init_mmu().
This is often because .early_init_mmu lacks a __init
annotation or the annotation of .hash__early_init_mmu is wrong.
The compiler is uninlining early_init_mmu and not putting it in an init
section because there is no annotation. Add it.
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Link: https://lore.kernel.org/r/20200429070247.1678172-1-npiggin@gmail.com
Geoff Levand [Sat, 16 May 2020 16:20:46 +0000 (09:20 -0700)]
powerpc/ps3: Add check for otheros image size
The ps3's otheros flash loader has a size limit of 16 MiB for the
uncompressed image. If that limit will be reached output the
flash image file as 'otheros-too-big.bld'.
ie. hstart is above hend, which indicates no huge page flush is
needed.
However the current logic incorrectly sets hflush = true in this case,
because hstart != hend.
That causes us to call __tlbie_va_range() passing hstart/hend, to do a
huge page flush even though we don't need to. __tlbie_va_range() will
skip the actual tlbie operation for start > end. But it will still end
up calling fixup_tlbie_va_range() and doing the TLB fixups in there,
which is harmless but unnecessary work.
Reported-by: Bharata B Rao <bharata@linux.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Drop else case, hflush is already false, flesh out change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200513030616.152288-1-aneesh.kumar@linux.ibm.com
Michael Ellerman [Wed, 20 May 2020 13:37:33 +0000 (23:37 +1000)]
Merge branch 'topic/uaccess-ppc' into next
Merge our uaccess-ppc topic branch. It is based on the uaccess topic
branch that we're sharing with Viro.
This includes the addition of user_[read|write]_access_begin(), as
well as some powerpc specific changes to our uaccess routines that
would conflict badly if merged separately.
Xmon allows overwriting breakpoints because it's supported by only
one DAWR. But with multiple DAWRs, overwriting becomes ambiguous
or unnecessary complicated. So let's not allow it.
Ravi Bangoria [Thu, 14 May 2020 11:17:39 +0000 (16:47 +0530)]
powerpc/watchpoint: Don't allow concurrent perf and ptrace events
With Book3s DAWR, ptrace and perf watchpoints on powerpc behaves
differently. Ptrace watchpoint works in one-shot mode and generates
signal before executing instruction. It's ptrace user's job to
single-step the instruction and re-enable the watchpoint. OTOH, in
case of perf watchpoint, kernel emulates/single-steps the instruction
and then generates event. If perf and ptrace creates two events with
same or overlapping address ranges, it's ambiguous to decide who
should single-step the instruction. Because of this issue, don't
allow perf and ptrace watchpoint at the same time if their address
range overlaps.
Ravi Bangoria [Thu, 14 May 2020 11:17:38 +0000 (16:47 +0530)]
powerpc/watchpoint: Prepare handler to handle more than one watchpoint
Currently we assume that we have only one watchpoint supported by hw.
Get rid of that assumption and use dynamic loop instead. This should
make supporting more watchpoints very easy.
With more than one watchpoint, exception handler needs to know which
DAWR caused the exception, and hw currently does not provide it. So
we need sw logic for the same. To figure out which DAWR caused the
exception, check all different combinations of user specified range,
DAWR address range, actual access range and DAWRX constrains. For ex,
if user specified range and actual access range overlaps but DAWRX is
configured for readonly watchpoint and the instruction is store, this
DAWR must not have caused exception.
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Reviewed-by: Michael Neuling <mikey@neuling.org>
[mpe: Unsplit multi-line printk() strings, fix some sparse warnings] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200514111741.97993-14-ravi.bangoria@linux.ibm.com
Ravi Bangoria [Thu, 14 May 2020 11:17:33 +0000 (16:47 +0530)]
powerpc/watchpoint: Disable all available watchpoints when !dawr_force_enable
Instead of disabling only first watchpoint, disable all available
watchpoints while clearing dawr_force_enable.
Callback function is used only for disabling watchpoint, rename it
to disable_dawrs_cb(). And null_brk parameter is not really required
while disabling watchpoint, remove it.
Ravi Bangoria [Thu, 14 May 2020 11:17:29 +0000 (16:47 +0530)]
powerpc/watchpoint/ptrace: Return actual num of available watchpoints
User can ask for num of available watchpoints(dbginfo.num_data_bps)
using ptrace(PPC_PTRACE_GETHWDBGINFO). Return actual number of
available watchpoints on the machine rather than hardcoded 1.
Ravi Bangoria [Thu, 14 May 2020 11:17:28 +0000 (16:47 +0530)]
powerpc/watchpoint: Introduce function to get nr watchpoints dynamically
So far we had only one watchpoint, so we have hardcoded HBP_NUM to 1.
But Power10 is introducing 2nd DAWR and thus kernel should be able to
dynamically find actual number of watchpoints supported by hw it's
running on. Introduce function for the same. Also convert HBP_NUM macro
to HBP_NUM_MAX, which will now represent maximum number of watchpoints
supported by Powerpc.
Jordan Niethe [Wed, 6 May 2020 03:40:49 +0000 (13:40 +1000)]
powerpc sstep: Add support for prefixed load/stores
This adds emulation support for the following prefixed integer
load/stores:
* Prefixed Load Byte and Zero (plbz)
* Prefixed Load Halfword and Zero (plhz)
* Prefixed Load Halfword Algebraic (plha)
* Prefixed Load Word and Zero (plwz)
* Prefixed Load Word Algebraic (plwa)
* Prefixed Load Doubleword (pld)
* Prefixed Store Byte (pstb)
* Prefixed Store Halfword (psth)
* Prefixed Store Word (pstw)
* Prefixed Store Doubleword (pstd)
* Prefixed Load Quadword (plq)
* Prefixed Store Quadword (pstq)
the follow prefixed floating-point load/stores:
* Prefixed Load Floating-Point Single (plfs)
* Prefixed Load Floating-Point Double (plfd)
* Prefixed Store Floating-Point Single (pstfs)
* Prefixed Store Floating-Point Double (pstfd)
and for the following prefixed VSX load/stores:
* Prefixed Load VSX Scalar Doubleword (plxsd)
* Prefixed Load VSX Scalar Single-Precision (plxssp)
* Prefixed Load VSX Vector [0|1] (plxv, plxv0, plxv1)
* Prefixed Store VSX Scalar Doubleword (pstxsd)
* Prefixed Store VSX Scalar Single-Precision (pstxssp)
* Prefixed Store VSX Vector [0|1] (pstxv, pstxv0, pstxv1)
Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Reviewed-by: Balamuruhan S <bala24@linux.ibm.com>
[mpe: Use CONFIG_PPC64 not __powerpc64__, use get_op()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200506034050.24806-30-jniethe5@gmail.com
Jordan Niethe [Wed, 6 May 2020 03:40:48 +0000 (13:40 +1000)]
powerpc: Support prefixed instructions in alignment handler
If a prefixed instruction results in an alignment exception, the
SRR1_PREFIXED bit is set. The handler attempts to emulate the
responsible instruction and then increment the NIP past it. Use
SRR1_PREFIXED to determine by how much the NIP should be incremented.
Prefixed instructions are not permitted to cross 64-byte boundaries. If
they do the alignment interrupt is invoked with SRR1 BOUNDARY bit set.
If this occurs send a SIGBUS to the offending process if in user mode.
If in kernel mode call bad_page_fault().
Jordan Niethe [Fri, 15 May 2020 02:12:55 +0000 (12:12 +1000)]
powerpc: Add prefixed instructions to instruction data type
For powerpc64, redefine the ppc_inst type so both word and prefixed
instructions can be represented. On powerpc32 the type will remain the
same. Update places which had assumed instructions to be 4 bytes long.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Reviewed-by: Alistair Popple <alistair@popple.id.au>
[mpe: Rework the get_user_inst() macros to be parameterised, and don't
assign to the dest if an error occurred. Use CONFIG_PPC64 not
__powerpc64__ in a few places. Address other comments from
Christophe. Fix some sparse complaints.] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200506034050.24806-24-jniethe5@gmail.com