Pull parisc architecture fixes from Helge Deller: "Fixes CPU hotplug, the parisc stack unwinder and two possible build errors in kprobes and ftrace area: - Fix CPU hotplug - Fix unaligned accesses and faults in stack unwinder - Fix potential build errors by always including asm-generic/kprobes.h - Fix build bug by add missing CONFIG_DYNAMIC_FTRACE check" * tag 'parisc-for-6.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: parisc: Fix stack unwinder parisc/kprobes: always include asm-generic/kprobes.h parisc/ftrace: add missing CONFIG_DYNAMIC_FTRACE check Revert "parisc: Only list existing CPUs in cpu_possible_mask"
The NOKPROBE_SYMBOL macro (and others) were moved to
asm-generic/kprobes.h in 2017 by commit 7d134b2ce639 ("kprobes: move
kprobe declarations to asm-generic/kprobes.h"), and this new header
was included by asm/kprobes.h unconditionally on all architectures.
When kprobe support was added to parisc in 2017 by commit
8858ac8e9e9b1 ("parisc: Implement kprobes"), that header was only
included when CONFIG_KPROBES was enabled.
This can lead to build failures when NOKPROBE_SYMBOL is used, but
CONFIG_KPROBES is disabled. This mistake however was never actually
noticed because linux/kprobes.h also includes asm-generic/kprobes.h
(though I do not understand why that is, because it also includes
asm/kprobes.h).
To prevent eventual build failures, I suggest to always include
asm-generic/kprobes.h on parisc, just like all the other architectures
do. This way, including asm/kprobes.h suffices, and nobody (outside
of arch/) ever needs to explicitly include asm-generic/kprobes.h.
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: Helge Deller <deller@gmx.de>
We've had issues with gcc and 'asm goto' before, and we created a
'asm_volatile_goto()' macro for that in the past: see commits
3f0116c3238a ("compiler/gcc4: Add quirk for 'asm goto' miscompilation
bug") and a9f180345f53 ("compiler/gcc4: Make quirk for
asm_volatile_goto() unconditional").
Then, much later, we ended up removing the workaround in commit
43c249ea0b1e ("compiler-gcc.h: remove ancient workaround for gcc PR
58670") because we no longer supported building the kernel with the
affected gcc versions, but we left the macro uses around.
Now, Sean Christopherson reports a new version of a very similar
problem, which is fixed by re-applying that ancient workaround. But the
problem in question is limited to only the 'asm goto with outputs'
cases, so instead of re-introducing the old workaround as-is, let's
rename and limit the workaround to just that much less common case.
It looks like there are at least two separate issues that all hit in
this area:
(a) some versions of gcc don't mark the asm goto as 'volatile' when it
has outputs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98619
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110420
which is easy to work around by just adding the 'volatile' by hand.
(b) Internal compiler errors:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110422
which are worked around by adding the extra empty 'asm' as a
barrier, as in the original workaround.
but the problem Sean sees may be a third thing since it involves bad
code generation (not an ICE) even with the manually added 'volatile'.
but the same old workaround works for this case, even if this feels a
bit like voodoo programming and may only be hiding the issue.
Reported-and-tested-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/all/20240208220604.140859-1-seanjc@google.com/
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Andrew Pinski <quic_apinski@quicinc.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The current exception handler implementation, which assists when accessing user space memory, may exhibit random data corruption if the compiler decides to use a different register than the specified register %r29 (defined in ASM_EXCEPTIONTABLE_REG) for the error code. If the compiler choose another register, the fault handler will nevertheless store -EFAULT into %r29 and thus trash whatever this register is used for. Looking at the assembly I found that this happens sometimes in emulate_ldd(). To solve the issue, the easiest solution would be if it somehow is possible to tell the fault handler which register is used to hold the error code. Using %0 or %1 in the inline assembly is not posssible as it will show up as e.g. %r29 (with the "%r" prefix), which the GNU assembler can not convert to an integer. This patch takes another, better and more flexible approach: We extend the __ex_table (which is out of the execution path) by one 32-word. In this word we tell the compiler to insert the assembler instruction "or %r0,%r0,%reg", where %reg references the register which the compiler choosed for the error return code. In case of an access failure, the fault handler finds the __ex_table entry and can examine the opcode. The used register is encoded in the lowest 5 bits, and the fault handler can then store -EFAULT into this register. Since we extend the __ex_table to 3 words we can't use the BUILDTIME_TABLE_SORT config option any longer. Signed-off-by: Helge Deller <deller@gmx.de> Cc: <stable@vger.kernel.org> # v6.0+
Pull percpu updates from Dennis Zhou: "Enable percpu page allocator for RISC-V. There are RISC-V configurations with sparse NUMA configurations and small vmalloc space causing dynamic percpu allocations to fail as the backing chunk stride is too far apart" * tag 'percpu-for-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu: riscv: Enable pcpu page first chunk allocator mm: Introduce flush_cache_vmap_early()
Pull asm-generic cleanups from Arnd Bergmann: "A series from Baoquan He cleans up the asm-generic/io.h to remove the ioremap_uc() definition from everything except x86, which still needs it for pre-PAT systems. This series notably contains a patch from Jiaxun Yang that converts MIPS to use asm-generic/io.h like every other architecture does, enabling future cleanups. Some of my own patches fix -Wmissing-prototype warnings in architecture specific code across several architectures. This is now needed as the warning is enabled by default. There are still some remaining warnings in minor platforms, but the series should catch most of the widely used ones make them more consistent with one another. David McKay fixes a bug in __generic_cmpxchg_local() when this is used on 64-bit architectures. This could currently only affect parisc64 and sparc64. Additional cleanups address from Linus Walleij, Uwe Kleine-König, Thomas Huth, and Kefeng Wang help reduce unnecessary inconsistencies between architectures" * tag 'asm-generic-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: Fix 32 bit __generic_cmpxchg_local Hexagon: Make pfn accessors statics inlines ARC: mm: Make virt_to_pfn() a static inline mips: remove extraneous asm-generic/iomap.h include sparc: Use $(kecho) to announce kernel images being ready arm64: vdso32: Define BUILD_VDSO32_64 to correct prototypes csky: fix arch_jump_label_transform_static override arch: add do_page_fault prototypes arch: add missing prepare_ftrace_return() prototypes arch: vdso: consolidate gettime prototypes arch: include linux/cpu.h for trap_init() prototype arch: fix asm-offsets.c building with -Wmissing-prototypes arch: consolidate arch_irq_work_raise prototypes hexagon: Remove CONFIG_HEXAGON_ARCH_VERSION from uapi header asm/io: remove unnecessary xlate_dev_mem_ptr() and unxlate_dev_mem_ptr() mips: io: remove duplicated codes arch/*/io.h: remove ioremap_uc in some architectures mips: add <asm-generic/io.h> including
The pcpu setup when using the page allocator sets up a new vmalloc mapping very early in the boot process, so early that it cannot use the flush_cache_vmap() function which may depend on structures not yet initialized (for example in riscv, we currently send an IPI to flush other cpus TLB). But on some architectures, we must call flush_cache_vmap(): for example, in riscv, some uarchs can cache invalid TLB entries so we need to flush the new established mapping to avoid taking an exception. So fix this by introducing a new function flush_cache_vmap_early() which is called right after setting the new page table entry and before accessing this new mapping. This new function implements a local flush tlb on riscv and is no-op for other architectures (same as today). Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Dennis Zhou <dennis@kernel.org>
Build is broken if CONFIG_DEBUG_BUGVERBOSE=n.
Fix it be using the correct asm operand number.
Signed-off-by: Helge Deller <deller@gmx.de>
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Fixes: fe76a1349f23 ("parisc: Use natural CPU alignment for bug_table")
Cc: stable@vger.kernel.org # v6.0+
Enable GENERIC_BUG_RELATIVE_POINTERS which will store 32-bit relative offsets to the bug address and the source file name instead of 64-bit absolute addresses. This effectively reduces the size of the bug_table[] array by half on 64-bit kernels. Signed-off-by: Helge Deller <deller@gmx.de>
Those return codes are only defined for the parisc architecture and are leftovers from when we wanted to be HP-UX compatible. They are not returned by any Linux kernel syscall but do trigger problems with the glibc strerrorname_np() and strerror() functions as reported in glibc issue #31080. There is no need to keep them, so simply remove them. Signed-off-by: Helge Deller <deller@gmx.de> Reported-by: Bruno Haible <bruno@clisp.org> Closes: https://sourceware.org/bugzilla/show_bug.cgi?id=31080 Cc: stable@vger.kernel.org