Commit Graph

1312 Commits

Author SHA1 Message Date
Helge Deller ea7dead204 parisc: Fix 64-bit userspace syscall path
commit d24449864d upstream.

Currently the glibc isn't yet ported to 64-bit for hppa, so
there is no usable userspace available yet.
But it's possible to manually build a static 64-bit binary
and run that for testing. One such 64-bit test program is
available at http://ftp.parisc-linux.org/src/64bit.tar.gz
and it shows various issues with the existing 64-bit syscall
path in the kernel.
This patch fixes those issues.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org      # v4.19+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-17 15:08:20 +02:00
Helge Deller afa9990523 parisc: Fix itlb miss handler for 64-bit programs
commit 9542130937 upstream.

For an itlb miss when executing code above 4 Gb on ILP64 adjust the
iasq/iaoq in the same way isr/ior was adjusted.  This fixes signal
delivery for the 64-bit static test program from
http://ftp.parisc-linux.org/src/64bit.tar.gz.  Note that signals are
handled by the signal trampoline code in the 64-bit VDSO which is mapped
into high userspace memory region above 4GB for 64-bit processes.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org	# v4.19+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-17 15:08:19 +02:00
Helge Deller 05c21f285d parisc: Use irq_enter_rcu() to fix warning at kernel/context_tracking.c:367
[ Upstream commit 73cb4a2d8d ]

Use irq*_rcu() functions to fix this kernel warning:

 WARNING: CPU: 0 PID: 0 at kernel/context_tracking.c:367 ct_irq_enter+0xa0/0xd0
 Modules linked in:
 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.7.0-rc3-64bit+ #1037
 Hardware name: 9000/785/C3700

 IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000412cd758 00000000412cd75c
  IIR: 03ffe01f    ISR: 0000000000000000  IOR: 0000000043c20c20
  CPU:        0   CR30: 0000000041caa000 CR31: 0000000000000000
  ORIG_R28: 0000000000000005
  IAOQ[0]: ct_irq_enter+0xa0/0xd0
  IAOQ[1]: ct_irq_enter+0xa4/0xd0
  RP(r2): irq_enter+0x34/0x68
 Backtrace:
  [<000000004034a3ec>] irq_enter+0x34/0x68
  [<000000004030dc48>] do_cpu_irq_mask+0xc0/0x450
  [<0000000040303070>] intr_return+0x0/0xc

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-09-04 13:17:36 +02:00
Arnd Bergmann 4e6367fe32 parisc: use correct compat recv/recvfrom syscalls
[ Upstream commit 20a5078734 ]

Johannes missed parisc back when he introduced the compat version
of these syscalls, so receiving cmsg messages that require a compat
conversion is still broken.

Use the correct calls like the other architectures do.

Fixes: 1dacc76d00 ("net/compat/wext: send different messages to compat tasks")
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-05 09:12:49 +02:00
Al Viro f24cac6459 parisc: add missing export of __cmpxchg_u8()
[ Upstream commit c57e5dccb0 ]

__cmpxchg_u8() had been added (initially) for the sake of
drivers/phy/ti/phy-tusb1210.c; the thing is, that drivers is
modular, so we need an export

Fixes: b344d6a83d "parisc: add support for cmpxchg on u8 pointers"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-16 13:32:02 +02:00
Max Kellermann d2e2cb5258 parisc/ftrace: add missing CONFIG_DYNAMIC_FTRACE check
[ Upstream commit 250f5402e6 ]

Fixes a bug revealed by -Wmissing-prototypes when
CONFIG_FUNCTION_GRAPH_TRACER is enabled but not CONFIG_DYNAMIC_FTRACE:

 arch/parisc/kernel/ftrace.c:82:5: error: no previous prototype for 'ftrace_enable_ftrace_graph_caller' [-Werror=missing-prototypes]
    82 | int ftrace_enable_ftrace_graph_caller(void)
       |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 arch/parisc/kernel/ftrace.c:88:5: error: no previous prototype for 'ftrace_disable_ftrace_graph_caller' [-Werror=missing-prototypes]
    88 | int ftrace_disable_ftrace_graph_caller(void)
       |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:21:46 -04:00
Helge Deller 1dd8449e20 parisc/firmware: Fix F-extend for PDC addresses
commit 735ae74f73 upstream.

When running with narrow firmware (64-bit kernel using a 32-bit
firmware), extend PDC addresses into the 0xfffffff0.00000000
region instead of the 0xf0f0f0f0.00000000 region.

This fixes the power button on the C3700 machine in qemu (64-bit CPU
with 32-bit firmware), and my assumption is that the previous code was
really never used (because most 64-bit machines have a 64-bit firmware),
or it just worked on very old machines because they may only decode
40-bit of virtual addresses.

Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 08:41:53 +01:00
Helge Deller 5e34fe50a9 parisc/pgtable: Do not drop upper 5 address bits of physical address
commit 166b0110d1 upstream.

When calculating the pfn for the iitlbt/idtlbt instruction, do not
drop the upper 5 address bits. This doesn't seem to have an effect
on physical hardware which uses less physical address bits, but in
qemu the missing bits are visible.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc:  <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:54:59 +00:00
Helge Deller 064c697cac parisc: Prevent booting 64-bit kernels on PA1.x machines
commit a406b8b424 upstream.

Bail out early with error message when trying to boot a 64-bit kernel on
32-bit machines. This fixes the previous commit to include the check for
true 64-bit kernels as well.

Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: 591d2108f3 ("parisc: Add runtime check to prevent PA2.0 kernels on PA1.x machines")
Cc:  <stable@vger.kernel.org> # v6.0+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:54:59 +00:00
Helge Deller 2081b2a15b parisc: irq: Make irq_stack_union static to avoid sparse warning
[ Upstream commit b1bef1388c ]

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 21:53:32 +02:00
Helge Deller f47efdffdc parisc: drivers: Fix sparse warning
[ Upstream commit b137b9d60b ]

Fix "warning: directive in macro's argument list" warning.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 21:53:32 +02:00
Helge Deller d653c35de0 parisc: Drop loops_per_jiffy from per_cpu struct
commit 93346da8ff upstream.

There is no need to keep a loops_per_jiffy value per cpu. Drop it.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-19 12:20:30 +02:00
Helge Deller 9f73fd6972 parisc: Fix /proc/cpuinfo output for lscpu
commit 9f5ba4b3e1 upstream.

The lscpu command is broken since commit cab56b51ec ("parisc: Fix
device names in /proc/iomem") added the PA pathname to all PA
devices, includig the CPUs.

lscpu parses /proc/cpuinfo and now believes it found different CPU
types since every CPU is listed with an unique identifier (PA
pathname).

Fix this problem by simply dropping the PA pathname when listing the
CPUs in /proc/cpuinfo. There is no need to show the pathname in this
procfs file.

Fixes: cab56b51ec ("parisc: Fix device names in /proc/iomem")
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v4.9+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-19 12:20:22 +02:00
Helge Deller 3f7625e086 parisc: Improve cache flushing for PCXL in arch_sync_dma_for_cpu()
[ Upstream commit 59fa12646d ]

Add comment in arch_sync_dma_for_device() and handle the direction flag in
arch_sync_dma_for_cpu().

When receiving data from the device (DMA_FROM_DEVICE) unconditionally
purge the data cache in arch_sync_dma_for_cpu().

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-06-21 15:45:36 +02:00
Helge Deller 518c39fc1e parisc: Fix flush_dcache_page() for usage from irq context
commit 61e150fb31 upstream.

Since at least kernel 6.1, flush_dcache_page() is called with IRQs
disabled, e.g. from aio_complete().

But the current implementation for flush_dcache_page() on parisc
unintentionally re-enables IRQs, which may lead to deadlocks.

Fix it by using xa_lock_irqsave() and xa_unlock_irqrestore()
for the flush_dcache_mmap_*lock() macros instead.

Cc: linux-parisc@vger.kernel.org
Cc: stable@kernel.org # 5.18+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 12:57:57 +01:00
Helge Deller c570dbf279 parisc: Allow to reboot machine after system halt
commit 2028315cf5 upstream.

In case a machine can't power-off itself on system shutdown,
allow the user to reboot it by pressing the RETURN key.

Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 12:57:57 +01:00
Helge Deller de0d7dd5ef parisc: Handle kgdb breakpoints only in kernel context
commit 6888ff04e3 upstream.

The kernel kgdb break instructions should only be handled when running
in kernel context.

Cc: <stable@vger.kernel.org> # v5.4+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 12:57:56 +01:00
Helge Deller e4b5264422 parisc: Fix argument pointer in real64_call_asm()
commit 6e3220ba33 upstream.

Fix the argument pointer (ap) to point to real-mode memory
instead of virtual memory.

It's interesting that this issue hasn't shown up earlier, as this could
have happened with any 64-bit PDC ROM code.

I just noticed it because I suddenly faced a HPMC while trying to execute
the 64-bit STI ROM code of an Visualize-FXe graphics card for the STI
text console.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17 11:47:35 +02:00
Helge Deller 71a4f39f99 parisc: Wire up PTRACE_GETREGS/PTRACE_SETREGS for compat case
commit 316f1f42b5 upstream.

Wire up the missing ptrace requests PTRACE_GETREGS, PTRACE_SETREGS,
PTRACE_GETFPREGS and PTRACE_SETFPREGS when running 32-bit applications
on 64-bit kernels.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 4.7+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-15 17:22:19 +01:00
Helge Deller 2982b473d7 parisc: Fix return code of pdc_iodc_print()
commit 5d1335dabb upstream.

There is an off-by-one if the printed string includes a new-line
char.

Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-15 17:22:19 +01:00
Eric W. Biederman d9c740c765 exit: Add and use make_task_dead.
commit 0e25498f8c upstream.

There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-01 08:23:19 +01:00
Helge Deller 5b700b9c04 parisc: Align parisc MADV_XXX constants with all other architectures
commit 71bdea6f79 upstream.

Adjust some MADV_XXX constants to be in sync what their values are on
all other platforms. There is currently no reason to have an own
numbering on parisc, but it requires workarounds in many userspace
sources (e.g. glibc, qemu, ...) - which are often forgotten and thus
introduce bugs and different behaviour on parisc.

A wrapper avoids an ABI breakage for existing userspace applications by
translating any old values to the new ones, so this change allows us to
move over all programs to the new ABI over time.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-14 10:16:51 +01:00
Jens Axboe dd26e2cec7 arch: ensure parisc/powerpc handle PF_IO_WORKER in copy_thread()
[ Upstream commit 0100e6bbdb ]

In the arch addition of PF_IO_WORKER, I missed parisc and powerpc for
some reason. Fix that up, ensuring they handle PF_IO_WORKER like they do
PF_KTHREAD in copy_thread().

Reported-by: Bruno Goncalves <bgoncalv@redhat.com>
Fixes: 4727dc20e0 ("arch: setup PF_IO_WORKER threads like PF_KTHREAD")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-04 11:39:23 +01:00
Jens Axboe 45b365bc6c parisc: add support for TIF_NOTIFY_SIGNAL
[ Upstream commit 18cb328128 ]

Wire up TIF_NOTIFY_SIGNAL handling for parisc.

Cc: linux-parisc@vger.kernel.org
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-04 11:39:19 +01:00
Helge Deller c9598cf629 parisc: Avoid printing the hardware path twice
commit 2b6ae0962b upstream.

Avoid that the hardware path is shown twice in the kernel log, and clean
up the output of the version numbers to show up in the same order as
they are listed in the hardware database in the hardware.c file.
Additionally, optimize the memory footprint of the hardware database
and mark some code as init code.

Fixes: cab56b51ec ("parisc: Fix device names in /proc/iomem")
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v4.9+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:14:27 +01:00
John David Anglin 7bbdf49e26 parisc: Flush kernel data mapping in set_pte_at() when installing pte for user page
[ Upstream commit 38860b2c8b ]

For years, there have been random segmentation faults in userspace on
SMP PA-RISC machines.  It occurred to me that this might be a problem in
set_pte_at().  MIPS and some other architectures do cache flushes when
installing PTEs with the present bit set.

Here I have adapted the code in update_mmu_cache() to flush the kernel
mapping when the kernel flush is deferred, or when the kernel mapping
may alias with the user mapping.  This simplifies calls to
update_mmu_cache().

I also changed the barrier in set_pte() from a compiler barrier to a
full memory barrier.  I know this change is not sufficient to fix the
problem.  It might not be needed.

I have had a few days of operation with 5.14.16 to 5.15.1 and haven't
seen any random segmentation faults on rp3440 or c8000 so far.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@kernel.org # 5.12+
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-23 14:16:56 +02:00
Helge Deller b00a56e647 parisc: Optimize per-pagetable spinlocks
[ Upstream commit b7795074a0 ]

On parisc a spinlock is stored in the next page behind the pgd which
protects against parallel accesses to the pgd. That's why one additional
page (PGD_ALLOC_ORDER) is allocated for the pgd.

Matthew Wilcox suggested that we instead should use a pointer in the
struct page table for this spinlock and noted, that the comments for the
PGD_ORDER and PMD_ORDER defines were wrong.

Both suggestions are addressed with this patch. Instead of having an own
spinlock to protect the pgd, we now switch to use the existing
page_table_lock.  Additionally, beside loading the pgd into cr25 in
switch_mm_irqs_off(), the physical address of this lock is loaded into
cr28 (tr4), so that we can avoid implementing a complicated lookup in
assembly for this lock in the TLB fault handlers.

The existing Hybrid L2/L3 page table scheme (where the pmd is adjacent
to the pgd) has been dropped with this patch.

Remove the locking in set_pte() and the huge-page pte functions too.
They trigger a spinlock recursion on 32bit machines and seem unnecessary.

Suggested-by: Matthew Wilcox <willy@infradead.org>
Fixes: b37d1c1898 ("parisc: Use per-pagetable spinlock")
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Stable-dep-of: 38860b2c8b ("parisc: Flush kernel data mapping in set_pte_at() when installing pte for user page")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-23 14:16:56 +02:00
Helge Deller 96d206d0a1 parisc: Add runtime check to prevent PA2.0 kernels on PA1.x machines
[ Upstream commit 591d2108f3 ]

If a 32-bit kernel was compiled for PA2.0 CPUs, it won't be able to run
on machines with PA1.x CPUs. Add a check and bail out early if a PA1.x
machine is detected.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 11:32:03 +02:00
Helge Deller df1d445e7f parisc: Fix exception handler for fldw and fstw instructions
commit 7ae1f5508d upstream.

The exception handler is broken for unaligned memory acceses with fldw
and fstw instructions, because it trashes or uses randomly some other
floating point register than the one specified in the instruction word
on loads and stores.

The instruction "fldw 0(addr),%fr22L" (and the other fldw/fstw
instructions) encode the target register (%fr22) in the rightmost 5 bits
of the instruction word. The 7th rightmost bit of the instruction word
defines if the left or right half of %fr22 should be used.

While processing unaligned address accesses, the FR3() define is used to
extract the offset into the local floating-point register set.  But the
calculation in FR3() was buggy, so that for example instead of %fr22,
register %fr12 [((22 * 2) & 0x1f) = 12] was used.

This bug has been since forever in the parisc kernel and I wonder why it
wasn't detected earlier. Interestingly I noticed this bug just because
the libime debian package failed to build on *native* hardware, while it
successfully built in qemu.

This patch corrects the bitshift and masking calculation in FR3().

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-31 17:15:13 +02:00
Helge Deller 043f4642c1 parisc: io_pgetevents_time64() needs compat syscall in 32-bit compat mode
commit 6431e92fc8 upstream.

For all syscalls in 32-bit compat mode on 64-bit kernels the upper
32-bits of the 64-bit registers are zeroed out, so a negative 32-bit
signed value will show up as positive 64-bit signed value.

This behaviour breaks the io_pgetevents_time64() syscall which expects
signed 64-bit values for the "min_nr" and "nr" parameters.
Fix this by switching to the compat_sys_io_pgetevents_time64() syscall,
which uses "compat_long_t" types for those parameters.

Cc: <stable@vger.kernel.org> # v5.1+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-21 15:15:23 +02:00
Helge Deller b0dfba6d3b parisc: Fix device names in /proc/iomem
commit cab56b51ec upstream.

Fix the output of /proc/iomem to show the real hardware device name
including the pa_pathname, e.g. "Merlin 160 Core Centronics [8:16:0]".
Up to now only the pa_pathname ("[8:16.0]") was shown.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v4.9+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-21 15:15:23 +02:00
Helge Deller a196f277c5 parisc: Merge model and model name into one line in /proc/cpuinfo
commit 5b89966bc9 upstream.

The Linux tool "lscpu" shows the double amount of CPUs if we have
"model" and "model name" in two different lines in /proc/cpuinfo.
This change combines the model and the model name into one line.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-12 12:25:29 +02:00
John David Anglin 1753a49e26 parisc: Fix patch code locking and flushing
[ Upstream commit a9fe7fa7d8 ]

This change fixes the following:

1) The flags variable is not initialized. Always use raw_spin_lock_irqsave
and raw_spin_unlock_irqrestore to serialize patching.

2) flush_kernel_vmap_range is primarily intended for DMA flushes. Since
__patch_text_multiple is often called with interrupts disabled, it is
better to directly call flush_kernel_dcache_range_asm and
flush_kernel_icache_range_asm. This avoids an extra call.

3) The final call to flush_icache_range is unnecessary.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 21:01:03 +02:00
John David Anglin 7e4967e913 parisc: Fix handling off probe non-access faults
[ Upstream commit e00b0a2ab8 ]

Currently, the parisc kernel does not fully support non-access TLB
fault handling for probe instructions. In the fast path, we set the
target register to zero if it is not a shadowed register. The slow
path is not implemented, so we call do_page_fault. The architecture
indicates that non-access faults should not cause a page fault from
disk.

This change adds to code to provide non-access fault support for
probe instructions. It also modifies the handling of faults on
userspace so that if the address lies in a valid VMA and the access
type matches that for the VMA, the probe target register is set to
one. Otherwise, the target register is set to zero.

This was done to make probe instructions more useful for userspace.
Probe instructions are not very useful if they set the target register
to zero whenever a page is not present in memory. Nominally, the
purpose of the probe instruction is determine whether read or write
access to a given address is allowed.

This fixes a problem in function pointer comparison noticed in the
glibc testsuite (stdio-common/tst-vfprintf-user-type). The same
problem is likely in glibc (_dl_lookup_address).

V2 adds flush and lpa instruction support to handle_nadtlb_fault.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:40:32 +02:00
Helge Deller 646b532f32 parisc/unaligned: Fix ldw() and stw() unalignment handlers
commit a972798368 upstream.

Fix 3 bugs:

a) emulate_stw() doesn't return the error code value, so faulting
instructions are not reported and aborted.

b) Tell emulate_ldw() to handle fldw_l as floating point instruction

c) Tell emulate_ldw() to handle ldw_m as integer instruction

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-02 11:42:46 +01:00
Helge Deller 397b5433f7 parisc/unaligned: Fix fldd and fstd unaligned handlers on 32-bit kernel
commit dd2288f4a0 upstream.

Usually the kernel provides fixup routines to emulate the fldd and fstd
floating-point instructions if they load or store 8-byte from/to a not
natuarally aligned memory location.

On a 32-bit kernel I noticed that those unaligned handlers didn't worked and
instead the application got a SEGV.
While checking the code I found two problems:

First, the OPCODE_FLDD_L and OPCODE_FSTD_L cases were ifdef'ed out by the
CONFIG_PA20 option, and as such those weren't built on a pure 32-bit kernel.
This is now fixed by moving the CONFIG_PA20 #ifdef to prevent the compilation
of OPCODE_LDD_L and OPCODE_FSTD_L only, and handling the fldd and fstd
instructions.

The second problem are two bugs in the 32-bit inline assembly code, where the
wrong registers where used. The calculation of the natural alignment used %2
(vall) instead of %3 (ior), and the first word was stored back to address %1
(valh) instead of %3 (ior).

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-02 11:42:46 +01:00
John David Anglin 3681e9f3f0 parisc: Avoid calling faulthandler_disabled() twice
[ Upstream commit 9e9d4b460f ]

In handle_interruption(), we call faulthandler_disabled() to check whether the
fault handler is not disabled. If the fault handler is disabled, we immediately
call do_page_fault(). It then calls faulthandler_disabled(). If disabled,
do_page_fault() attempts to fixup the exception by jumping to no_context:

no_context:

        if (!user_mode(regs) && fixup_exception(regs)) {
                return;
        }

        parisc_terminate("Bad Address (null pointer deref?)", regs, code, address);

Apart from the error messages, the two blocks of code perform the same
function.

We can avoid two calls to faulthandler_disabled() by a simple revision
to the code in handle_interruption().

Note: I didn't try to fix the formatting of this code block.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 10:54:20 +01:00
Helge Deller d01e9ce1af parisc: Clear stale IIR value on instruction access rights trap
[ Upstream commit 484730e586 ]

When a trap 7 (Instruction access rights) occurs, this means the CPU
couldn't execute an instruction due to missing execute permissions on
the memory region.  In this case it seems the CPU didn't even fetched
the instruction from memory and thus did not store it in the cr19 (IIR)
register before calling the trap handler. So, the trap handler will find
some random old stale value in cr19.

This patch simply overwrites the stale IIR value with a constant magic
"bad food" value (0xbaadf00d), in the hope people don't start to try to
understand the various random IIR values in trap 7 dumps.

Noticed-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-05 12:40:29 +01:00
John David Anglin 5deeb9ad59 parisc: Correct completer in lws start
commit 8f66fce0f4 upstream.

The completer in the "or,ev %r1,%r30,%r30" instruction is reversed, so we are
not clipping the LWS number when we are called from a 32-bit process (W=0).
We need to nulify the following depdi instruction when the least-significant
bit of %r30 is 1.

If the %r20 register is not clipped, a user process could perform a LWS call
that would branch to an undefined location in the kernel and potentially crash
the machine.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # 4.19+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-29 12:26:02 +01:00
Helge Deller dbe73dace9 parisc: Mark cr16 CPU clocksource unstable on all SMP machines
commit afdb4a5b1d upstream.

In commit c8c3735997 ("parisc: Enhance detection of synchronous cr16
clocksources") I assumed that CPUs on the same physical core are syncronous.
While booting up the kernel on two different C8000 machines, one with a
dual-core PA8800 and one with a dual-core PA8900 CPU, this turned out to be
wrong. The symptom was that I saw a jump in the internal clocks printed to the
syslog and strange overall behaviour.  On machines which have 4 cores (2
dual-cores) the problem isn't visible, because the current logic already marked
the cr16 clocksource unstable in this case.

This patch now marks the cr16 interval timers unstable if we have more than one
CPU in the system, and it fixes this issue.

Fixes: c8c3735997 ("parisc: Enhance detection of synchronous cr16 clocksources")
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v5.15+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-08 09:03:29 +01:00
Helge Deller 6ca32e2e77 Revert "parisc: Fix backtrace to always include init funtion names"
commit 98400ad75e upstream.

This reverts commit 279917e27e.

With the CONFIG_HARDENED_USERCOPY option enabled, this patch triggers
kernel bugs at runtime:

  usercopy: Kernel memory overwrite attempt detected to kernel text (offset 2084839, size 6)!
  kernel BUG at mm/usercopy.c:99!
 Backtrace:
  IAOQ[0]: usercopy_abort+0xc4/0xe8
  [<00000000406ed1c8>] __check_object_size+0x174/0x238
  [<00000000407086d4>] copy_strings.isra.0+0x3e8/0x708
  [<0000000040709a20>] do_execveat_common.isra.0+0x1bc/0x328
  [<000000004070b760>] compat_sys_execve+0x7c/0xb8
  [<0000000040303eb8>] syscall_exit+0x0/0x14

The problem is, that we have an init section of at least 2MB size which
starts at _stext and is freed after bootup.

If then later some kernel data is (temporarily) stored in this free
memory, check_kernel_text_object() will trigger a bug since the data
appears to be inside the kernel text (>=_stext) area:
        if (overlaps(ptr, len, _stext, _etext))
                usercopy_abort("kernel text");

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@kernel.org # 5.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-01 09:19:00 +01:00
Sven Schnelle c49bfdfe53 parisc/entry: fix trace test in syscall exit path
commit 3ec18fc783 upstream.

commit 8779e05ba8 ("parisc: Fix ptrace check on syscall return")
fixed testing of TI_FLAGS. This uncovered a bug in the test mask.
syscall_restore_rfi is only used when the kernel needs to exit to
usespace with single or block stepping and the recovery counter
enabled. The test however used _TIF_SYSCALL_TRACE_MASK, which
includes a lot of bits that shouldn't be tested here.

Fix this by using TIF_SINGLESTEP and TIF_BLOCKSTEP directly.

I encountered this bug by enabling syscall tracepoints. Both in qemu and
on real hardware. As soon as i enabled the tracepoint (sys_exit_read,
but i guess it doesn't really matter which one), i got random page
faults in userspace almost immediately.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-21 13:46:36 +01:00
Helge Deller fc42bbb782 parisc: Fix backtrace to always include init funtion names
commit 279917e27e upstream.

I noticed that sometimes at kernel startup the backtraces did not
included the function names of init functions. Their address were not
resolved to function names and instead only the address was printed.

Debugging shows that the culprit is is_ksym_addr() which is called
by the backtrace functions to check if an address belongs to a function in
the kernel. The problem occurs only for CONFIG_KALLSYMS_ALL=y.

When looking at is_ksym_addr() one can see that for CONFIG_KALLSYMS_ALL=y
the function only tries to resolve the address via is_kernel() function,
which checks like this:
	if (addr >= _stext && addr <= _end)
                return 1;
On parisc the init functions are located before _stext, so this check fails.
Other platforms seem to have all functions (including init functions)
behind _stext.

The following patch moves the _stext symbol at the beginning of the
kernel and thus includes the init section. This fixes the check and does
not seem to have any negative side effects on where the kernel mapping
happens in the map_pages() function in arch/parisc/mm/init.c.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@kernel.org # 5.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-18 14:04:28 +01:00
Sven Schnelle 0c5e946794 parisc/kgdb: add kgdb_roundup() to make kgdb work with idle polling
[ Upstream commit 66e29fcda1 ]

With idle polling, IPIs are not sent when a CPU idle, but queued
and run later from do_idle(). The default kgdb_call_nmi_hook()
implementation gets the pointer to struct pt_regs from get_irq_reqs(),
which doesn't work in that case because it was not called from the
IPI interrupt handler. Fix it by defining our own kgdb_roundup()
function which sents an IPI_ENTER_KGDB. When that IPI is received
on the target CPU kgdb_nmicallback() is called.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-18 14:04:01 +01:00
Sven Schnelle a1ec31a0be parisc/unwind: fix unwinder when CONFIG_64BIT is enabled
[ Upstream commit 8e0ba125c2 ]

With 64 bit kernels unwind_special() is not working because
it compares the pc to the address of the function descriptor.
Add a helper function that compares pc with the dereferenced
address. This fixes all of the backtraces on my c8000. Without
this changes, a lot of backtraces are missing in kdb or the
show-all-tasks command from /proc/sysrq-trigger.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-18 14:04:01 +01:00
Helge Deller 32498b8889 parisc: Fix ptrace check on syscall return
commit 8779e05ba8 upstream.

The TIF_XXX flags are stored in the flags field in the thread_info
struct (TI_FLAGS), not in the flags field of the task_struct structure
(TASK_FLAGS).

It seems this bug didn't generate any important side-effects, otherwise it
wouldn't have went unnoticed for 12 years (since v2.6.32).

Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: ecd3d4bc06 ("parisc: stop using task->ptrace for {single,block}step flags")
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-18 14:03:37 +01:00
Mikulas Patocka 7a5756e905 parisc: fix crash with signals and alloca
commit 030f653078 upstream.

I was debugging some crashes on parisc and I found out that there is a
crash possibility if a function using alloca is interrupted by a signal.
The reason for the crash is that the gcc alloca implementation leaves
garbage in the upper 32 bits of the sp register. This normally doesn't
matter (the upper bits are ignored because the PSW W-bit is clear),
however the signal delivery routine in the kernel uses full 64 bits of sp
and it fails with -EFAULT if the upper 32 bits are not zero.

I created this program that demonstrates the problem:

#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <alloca.h>

static __attribute__((noinline,noclone)) void aa(int *size)
{
	void * volatile p = alloca(-*size);
	while (1) ;
}

static void handler(int sig)
{
	write(1, "signal delivered\n", 17);
	_exit(0);
}

int main(void)
{
	int size = -0x100;
	signal(SIGALRM, handler);
	alarm(1);
	aa(&size);
}

If you compile it with optimizations, it will crash.
The "aa" function has this disassembly:

000106a0 <aa>:
   106a0:       08 03 02 41     copy r3,r1
   106a4:       08 1e 02 43     copy sp,r3
   106a8:       6f c1 00 80     stw,ma r1,40(sp)
   106ac:       37 dc 3f c1     ldo -20(sp),ret0
   106b0:       0c 7c 12 90     stw ret0,8(r3)
   106b4:       0f 40 10 9c     ldw 0(r26),ret0		; ret0 = 0x00000000FFFFFF00
   106b8:       97 9c 00 7e     subi 3f,ret0,ret0	; ret0 = 0xFFFFFFFF0000013F
   106bc:       d7 80 1c 1a     depwi 0,31,6,ret0	; ret0 = 0xFFFFFFFF00000100
   106c0:       0b 9e 0a 1e     add,l sp,ret0,sp	;   sp = 0xFFFFFFFFxxxxxxxx
   106c4:       e8 1f 1f f7     b,l,n 106c4 <aa+0x24>,r0

This patch fixes the bug by truncating the "usp" variable to 32 bits.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-18 13:40:35 +02:00
Helge Deller 0085646e02 Revert "parisc: Add assembly implementations for memset, strlen, strcpy, strncpy and strcat"
commit f6a3308d6f upstream.

This reverts commit 83af58f806.

It turns out that at least the assembly implementation for strncpy() was
buggy.  Revert the whole commit and return back to the default coding.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v5.4+
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-03 10:09:31 +02:00
Valentin Schneider 3c51d82d0b sched/core: Initialize the idle task with preemption disabled
[ Upstream commit f1a0a376ca ]

As pointed out by commit

  de9b8f5dcb ("sched: Fix crash trying to dequeue/enqueue the idle thread")

init_idle() can and will be invoked more than once on the same idle
task. At boot time, it is invoked for the boot CPU thread by
sched_init(). Then smp_init() creates the threads for all the secondary
CPUs and invokes init_idle() on them.

As the hotplug machinery brings the secondaries to life, it will issue
calls to idle_thread_get(), which itself invokes init_idle() yet again.
In this case it's invoked twice more per secondary: at _cpu_up(), and at
bringup_cpu().

Given smp_init() already initializes the idle tasks for all *possible*
CPUs, no further initialization should be required. Now, removing
init_idle() from idle_thread_get() exposes some interesting expectations
with regards to the idle task's preempt_count: the secondary startup always
issues a preempt_disable(), requiring some reset of the preempt count to 0
between hot-unplug and hotplug, which is currently served by
idle_thread_get() -> idle_init().

Given the idle task is supposed to have preemption disabled once and never
see it re-enabled, it seems that what we actually want is to initialize its
preempt_count to PREEMPT_DISABLED and leave it there. Do that, and remove
init_idle() from idle_thread_get().

Secondary startups were patched via coccinelle:

  @begone@
  @@

  -preempt_disable();
  ...
  cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210512094636.2958515-1-valentin.schneider@arm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14 16:55:50 +02:00
John David Anglin 25ceaadccb parisc: Bump 64-bit IRQ stack size to 64 KB
[ Upstream commit 31680c1d15 ]

Bump 64-bit IRQ stack size to 64 KB.

I had a kernel IRQ stack overflow on the mx3210 debian buildd machine.  This patch increases the
64-bit IRQ stack size to 64 KB.  The 64-bit stack size needs to be larger than the 32-bit stack
size since registers are twice as big.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-07 12:34:13 +01:00