commit 166b0110d1ee53290bd11618df6e3991c117495a 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>
commit a406b8b424fa01f244c1aab02ba186258448c36b 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: 591d2108f3abc ("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>
commit 93346da8ff47cc00f953c7f38a2d6ba11977fc42 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>
commit 9f5ba4b3e1b3c123eeca5d2d09161e8720048b5c upstream.
The lscpu command is broken since commit cab56b51ec0e ("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: cab56b51ec0e ("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>
[ Upstream commit 59fa12646d9f56c842b4d5b6418ed77af625c588 ]
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>
commit 61e150fb310729c98227a5edf6e4a3619edc3702 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>
commit 2028315cf59bb899a5ac7e87dc48ecb8fac7ac24 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>
commit 6888ff04e37d01295620a73f3f7efbc79f6ef152 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>
commit 6e3220ba3323a2c24be834aebf5d6e9f89d0993f 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>
commit 5d1335dabb3c493a3d6d5b233953b6ac7b6c1ff2 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>
commit 0e25498f8cd43c1b5aa327f373dd094e9a006da7 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>
commit 71bdea6f798b425bc0003780b13e3fdecb16a010 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>
[ Upstream commit 0100e6bbdbb79404e56939313662b42737026574 ]
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: 4727dc20e042 ("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>
commit 2b6ae0962b421103feb41a80406732944b0665b3 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: cab56b51ec0e ("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>
[ Upstream commit 38860b2c8bb1b92f61396eb06a63adff916fc31d ]
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>
[ Upstream commit b7795074a04669d0a023babf786d29bf67c68783 ]
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: 38860b2c8bb1 ("parisc: Flush kernel data mapping in set_pte_at() when installing pte for user page")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 591d2108f3abc4db9f9073cae37cf3591fd250d6 ]
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>
commit 7ae1f5508d9a33fd58ed3059bd2d569961e3b8bd 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>
commit 6431e92fc827bdd2d28f79150d90415ba9ce0d21 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>
commit cab56b51ec0e69128909cef4650e1907248d821b 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>
commit 5b89966bc96a06f6ad65f64ae4b0461918fcc9d3 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>
[ Upstream commit a9fe7fa7d874a536e0540469f314772c054a0323 ]
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>
[ Upstream commit e00b0a2ab8ec019c344e53bfc76e31c18bb587b7 ]
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>
commit a97279836867b1cb50a3d4f0b1bf60e0abe6d46c 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>
commit dd2288f4a020d693360e3e8d72f8b9d9c25f5ef6 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>
[ Upstream commit 9e9d4b460f23bab61672eae397417d03917d116c ]
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>
[ Upstream commit 484730e5862f6b872dca13840bed40fd7c60fa26 ]
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>
commit 8f66fce0f46560b9e910787ff7ad0974441c4f9c 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>
commit afdb4a5b1d340e4afffc65daa21cc71890d7d589 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>
commit 98400ad75e95860e9a10ec78b0b90ab66184a2ce upstream.
This reverts commit 279917e27edc293eb645a25428c6ab3f3bca3f86.
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>
commit 3ec18fc7831e7d79e2d536dd1f3bc0d3ba425e8a upstream.
commit 8779e05ba8aa ("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>
commit 279917e27edc293eb645a25428c6ab3f3bca3f86 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>
[ Upstream commit 66e29fcda1824f0427966fbee2bd2c85bf362c82 ]
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>
[ Upstream commit 8e0ba125c2bf1030af3267058019ba86da96863f ]
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>
commit 8779e05ba8aaffec1829872ef9774a71f44f6580 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>
commit 030f653078316a9cc9ca6bd1b0234dcf858be35d 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>
[ Upstream commit f1a0a376ca0c4ef1fc3d24e3e502acbb5b795674 ]
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>
[ Upstream commit 31680c1d1595a59e17c14ec036b192a95f8e5f4a ]
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>
commit 00e35f2b0e8acb88d4e1aa96ff0490e3bfe46580 upstream.
When building a kernel without module support, the CONFIG_MLONGCALL option
needs to be enabled in order to reach symbols which are outside of a 22-bit
branch.
This patch changes the autodetection in the Kconfig script to always enable
CONFIG_MLONGCALL when modules are disabled and uses a far call to
preempt_schedule_irq() in intr_do_preempt() to reach the symbol in all cases.
Signed-off-by: Helge Deller <deller@gmx.de>
Reported-by: kernel test robot <lkp@intel.com>
Cc: stable@vger.kernel.org # v5.6+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We call arch_cpu_idle() with RCU disabled, but then use
local_irq_{en,dis}able(), which invokes tracing, which relies on RCU.
Switch all arch_cpu_idle() implementations to use
raw_local_irq_{en,dis}able() and carefully manage the
lockdep,rcu,tracing state like we do in entry.
(XXX: we really should change arch_cpu_idle() to not return with
interrupts enabled)
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
Pull more parisc updates from Helge Deller:
- During this merge window O_NONBLOCK was changed to become 000200000,
but we missed that the syscalls timerfd_create(), signalfd4(),
eventfd2(), pipe2(), inotify_init1() and userfaultfd() do a strict
bit-wise check of the flags parameter.
To provide backward compatibility with existing userspace we
introduce parisc specific wrappers for those syscalls which filter
out the old O_NONBLOCK value and replaces it with the new one.
- Prevent HIL bus driver to get stuck when keyboard or mouse isn't
attached
- Improve error return codes when setting rtc time
- Minor documentation fix in pata_ns87415.c
* 'parisc-5.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
ata: pata_ns87415.c: Document support on parisc with superio chip
parisc: Add wrapper syscalls to fix O_NONBLOCK flag usage
hil/parisc: Disable HIL driver when it gets stuck
parisc: Improve error return codes when setting rtc time
The commit 75ae04206a ("parisc: Define O_NONBLOCK to become
000200000") changed the O_NONBLOCK constant to have only one bit set
(like all other architectures). This change broke some existing
userspace code (e.g. udevadm, systemd-udevd, elogind) which called
specific syscalls which do strict value checking on their flag
parameter.
This patch adds wrapper functions for the relevant syscalls. The
wrappers masks out any old invalid O_NONBLOCK flags, reports in the
syslog if the old O_NONBLOCK value was used and then calls the target
syscall with the new O_NONBLOCK value.
Fixes: 75ae04206a ("parisc: Define O_NONBLOCK to become 000200000")
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: Meelis Roos <mroos@linux.ee>
Tested-by: Jeroen Roovers <jer@xs4all.nl>
Pull arch task_work cleanups from Jens Axboe:
"Two cleanups that don't fit other categories:
- Finally get the task_work_add() cleanup done properly, so we don't
have random 0/1/false/true/TWA_SIGNAL confusing use cases. Updates
all callers, and also fixes up the documentation for
task_work_add().
- While working on some TIF related changes for 5.11, this
TIF_NOTIFY_RESUME cleanup fell out of that. Remove some arch
duplication for how that is handled"
* tag 'arch-cleanup-2020-10-22' of git://git.kernel.dk/linux-block:
task_work: cleanup notification modes
tracehook: clear TIF_NOTIFY_RESUME in tracehook_notify_resume()
The HP 730 machine returned strange errors when I tried setting the rtc
time. Add some debug code to improve the possibility to trace errors
and document that hppa probably has as Y2k38 problem.
Signed-off-by: Helge Deller <deller@gmx.de>