diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2024-02-01 12:32:43 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2024-02-01 12:32:43 -0800 |
commit | 91481c9092465d68bcb4540ac0dbfd65024a0170 (patch) | |
tree | a4a96bf2ed1b1e164a0724c6ec0629b7a3997553 /arch/parisc/mm/fault.c | |
parent | a412682659b3832ac6f1a301e1c147027926f605 (diff) | |
parent | 913b9d443a0180cf0de3548f1ab3149378998486 (diff) |
Merge tag 'parisc-for-6.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc architecture fixes from Helge Deller:
"The current exception handler, which helps on kernel accesses to
userspace, may exhibit data corruption. The problem is that it is not
guaranteed that the compiler will use the processor register we
specified in the source code, but may choose another register which
then will lead to silent register- and data corruption. To fix this
issue we now use another strategy to help the exception handler to
always find and set the error code into the correct CPU register.
The other fixes are small: fixing CPU hotplug bringup, fix the page
alignment of the RO_DATA section, added a check for the calculated
cache stride and fix possible hangups when printing longer output at
bootup when running on serial console.
Most of the patches are tagged for stable series.
- Fix random data corruption triggered by exception handler
- Fix crash when setting up BTLB at CPU bringup
- Prevent hung tasks when printing inventory on serial console
- Make RO_DATA page aligned in vmlinux.lds.S
- Add check for valid cache stride size"
* tag 'parisc-for-6.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: BTLB: Fix crash when setting up BTLB at CPU bringup
parisc: Fix random data corruption from exception handler
parisc: Drop unneeded semicolon in parse_tree_node()
parisc: Prevent hung tasks when printing inventory on serial console
parisc: Check for valid stride size for cache flushes
parisc: Make RO_DATA page aligned in vmlinux.lds.S
Diffstat (limited to 'arch/parisc/mm/fault.c')
-rw-r--r-- | arch/parisc/mm/fault.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c index 2fe5b44986e0..c39de84e98b0 100644 --- a/arch/parisc/mm/fault.c +++ b/arch/parisc/mm/fault.c @@ -150,11 +150,16 @@ int fixup_exception(struct pt_regs *regs) * Fix up get_user() and put_user(). * ASM_EXCEPTIONTABLE_ENTRY_EFAULT() sets the least-significant * bit in the relative address of the fixup routine to indicate - * that gr[ASM_EXCEPTIONTABLE_REG] should be loaded with - * -EFAULT to report a userspace access error. + * that the register encoded in the "or %r0,%r0,register" + * opcode should be loaded with -EFAULT to report a userspace + * access error. */ if (fix->fixup & 1) { - regs->gr[ASM_EXCEPTIONTABLE_REG] = -EFAULT; + int fault_error_reg = fix->err_opcode & 0x1f; + if (!WARN_ON(!fault_error_reg)) + regs->gr[fault_error_reg] = -EFAULT; + pr_debug("Unalignment fixup of register %d at %pS\n", + fault_error_reg, (void*)regs->iaoq[0]); /* zero target register for get_user() */ if (parisc_acctyp(0, regs->iir) == VM_READ) { |