BMC/Intel-BMC/linux.git/arch/parisc/include/asm, branch dev-5.15-intel

parisc: Fix handling off probe non-access faults

2022-04-08T12:23:56+00:00

[ 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 Signed-off-by: Helge Deller Signed-off-by: Sasha Levin

parisc: Show error if wrong 32/64-bit compiler is being used

2022-02-23T11:03:03+00:00

commit b160628e9ebcdc85d0db9d7f423c26b3c7c179d0 upstream. It happens quite often that people use the wrong compiler to build the kernel: make ARCH=parisc -> builds the 32-bit kernel make ARCH=parisc64 -> builds the 64-bit kernel This patch adds a sanity check which errors out with an instruction how use the correct ARCH= option. Signed-off-by: Helge Deller Cc: stable@vger.kernel.org # v5.15+ Signed-off-by: Greg Kroah-Hartman

parisc: Fix lpa and lpa_user defines

2022-01-27T10:05:12+00:00

commit db19c6f1a2a353cc8dec35b4789733a3cf6e2838 upstream. While working on the rewrite to the light-weight syscall and futex code, I experimented with using a hash index based on the user physical address of atomic variable. This exposed two problems with the lpa and lpa_user defines. Because of the copy instruction, the pa argument needs to be an early clobber argument. This prevents gcc from allocating the va and pa arguments to the same register. Secondly, the lpa instruction can cause a page fault so we need to catch exceptions. Signed-off-by: John David Anglin Fixes: 116d753308cf ("parisc: Use lpa instruction to load physical addresses in driver code") Signed-off-by: Helge Deller Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Greg Kroah-Hartman

parisc: Fix mask used to select futex spinlock

2021-12-29T11:28:53+00:00

commit d3a5a68cff47f6eead84504c3c28376b85053242 upstream. The address bits used to select the futex spinlock need to match those used in the LWS code in syscall.S. The mask 0x3f8 only selects 7 bits. It should select 8 bits. This change fixes the glibc nptl/tst-cond24 and nptl/tst-cond25 tests. Signed-off-by: John David Anglin Fixes: 53a42b6324b8 ("parisc: Switch to more fine grained lws locks") Cc: stable@vger.kernel.org # 5.10+ Signed-off-by: Helge Deller Signed-off-by: Greg Kroah-Hartman

Revert "parisc: Reduce sigreturn trampoline to 3 instructions"

2021-11-25T08:48:44+00:00

commit 79df39d535c7a3770856fe9f5aba8c0ad1eebdb6 upstream. This reverts commit e4f2006f1287e7ea17660490569cff323772dac4. This patch shows problems with signal handling. Revert it for now. Signed-off-by: Helge Deller Cc: # v5.15 Signed-off-by: Greg Kroah-Hartman

parisc: Flush kernel data mapping in set_pte_at() when installing pte for user page

2021-11-18T18:17:14+00:00

commit 38860b2c8bb1b92f61396eb06a63adff916fc31d upstream. 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 Signed-off-by: Helge Deller Cc: stable@kernel.org # 5.12+ Signed-off-by: Greg Kroah-Hartman

parisc: Use absolute_pointer() to define PAGE0

2021-09-16T06:35:42+00:00

Use absolute_pointer() wrapper for PAGE0 to avoid this compiler warning: arch/parisc/kernel/setup.c: In function 'start_parisc': error: '__builtin_memcmp_eq' specified bound 8 exceeds source size 0 Signed-off-by: Helge Deller Co-Developed-by: Guenter Roeck Suggested-by: Linus Torvalds

parisc: Implement __get/put_kernel_nofault()

2021-09-09T20:53:09+00:00

Remove CONFIG_SET_FS from parisc, so we need to add __get_kernel_nofault() and __put_kernel_nofault(), define HAVE_GET_KERNEL_NOFAULT and remove set_fs(), get_fs(), load_sr2(), thread_info->addr_limit, KERNEL_DS and USER_DS. The nice side-effect of this patch is that we now can directly access userspace via sr3 without the need to use a temporary sr2 which is either copied from sr3 or set to zero (for kernel space). Signed-off-by: Helge Deller Suggested-by: Arnd Bergmann

parisc: Reduce sigreturn trampoline to 3 instructions

2021-09-09T10:44:31+00:00

We can move the INSN_LDI_R20 instruction into the branch delay slot. Signed-off-by: Helge Deller

parisc: Drop strnlen_user() in favour of generic version

2021-09-09T10:44:30+00:00

As suggested by Arnd Bergmann, drop the parisc version of strnlen_user() and switch to the generic version. Suggested-by: Arnd Bergmann Acked-by: Arnd Bergmann Signed-off-by: Helge Deller