user/sven/linux.git/arch/mips/include, branch v3.7.3

MIPS: Avoid mcheck by flushing page range in huge_ptep_set_access_flags()

2012-12-04T15:57:54Z

Problem: 1) Huge page mapping of anonymous memory is initially invalid. Will be faulted in by copy-on-write mechanism. 2) Userspace attempts store at the end of the huge mapping. 3) TLB Refill exception handler fill TLB with a normal (4K sized) invalid page at the end of the huge mapping virtual address range. 4) Userspace restarted, and re-attempts the store at the end of the huge mapping. 5) Page from #3 is invalid, we get a fault and go to the hugepage fault handler. This tries to map a huge page and calls huge_ptep_set_access_flags() to install the mapping. 6) We just call the generic ptep_set_access_flags() to set up the page tables, but the flush there assumes a normal (4K sized) page and only tries to flush the first part of the huge page virtual address out of the TLB, since the existing entry from step #3 doesn't conflict, nothing is flushed. 7) We attempt to load the mapping into the TLB, but because it conflicts with the entry from step #3, we get a Machine Check exception. The fix: Flush the entire rage covered by the huge page in huge_ptep_set_access_flags(), and remove the optimization in local_flush_tlb_range() so that the flush actually does the correct thing. Signed-off-by: David Daney Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Cc: Hillf Danton Patchwork: https://patchwork.linux-mips.org/patch/4661/ Signed-off-by: Ralf Baechle (cherry picked from commit dd617f258cc39d36be26afee9912624a2d23112c)

MIPS: Make irqflags.h functions preempt-safe for non-mipsr2 cpus

2012-11-09T09:59:21Z

For non MIPSr2 processors, such as the BMIPS 5000, calls to arch_local_irq_disable() and others may be preempted, and in doing so a stale value may be restored to c0_status. This fix disables preemption for such processors prior to the call and enables it after the call. Those functions that needed this fix have been "outlined" to mips-atomic.c, as they are no longer good candidates for inlining. This bug was observed in a BMIPS 5000, occuring once every few hours in a continuous reboot test. It was traced to the write_lock_irq() function which was being invoked in release_task() in exit.c. By placing a number of "nops" inbetween the mfc0/mtc0 pair in arch_local_irq_disable(), which is called by write_lock_irq(), we were able to greatly increase the occurance of this bug. Similarly, the application of this commit silenced the bug. Signed-off-by: Jim Quinlan Cc: linux-mips@linux-mips.org Cc: David Daney Cc: Kevin Cernekee cernekee@gmail.com Cc: Jim Quinlan Patchwork: https://patchwork.linux-mips.org/patch/4321/ Signed-off-by: Ralf Baechle

MIPS: Remove irqflags.h dependency from bitops.h

2012-11-09T09:59:10Z

The "else clause" of most functions in bitops.h invoked raw_local_irq_{save,restore}() and in doing so had a dependency on irqflags.h. This fix moves said code to bitops.c, removing the dependency. Signed-off-by: Jim Quinlan Cc: linux-mips@linux-mips.org Cc: David Daney Cc: Kevin Cernekee cernekee@gmail.com Cc: Jim Quinlan Patchwork: https://patchwork.linux-mips.org/patch/4320/ Signed-off-by: Ralf Baechle

MIPS: bitops.h: Change use of 'unsigned short' to 'int'

2012-11-09T09:58:50Z

[ralf@linux-mips.org: No functional change but it's consistent with how use types elsewhere in the code.] Signed-off-by: Jim Quinlan Cc: linux-mips@linux-mips.org Cc: David Daney Cc: Kevin Cernekee cernekee@gmail.com Cc: Jim Quinlan Patchwork: https://patchwork.linux-mips.org/patch/4319/ Signed-off-by: Ralf Baechle

MIPS: compat: Delete now unused TIF_32BIT.

2012-11-09T09:58:36Z

Signed-off-by: Ralf Baechle

MIPS: compat: Implement is_compat_task() by testing for 32-bit address space.

2012-11-09T09:58:29Z

So far is_compat_task() was testing for 32-bit registers if O32 support was enabled and if O32 support was disabled but N32 enabled it was testing for 32-bit address space. So if both O32 and N32 were enabled a N32 task was not considered a compat task, whops. This still leaves potential cases where O32 and N32 need different treatment unsolved. But that's another commit. Signed-off-by: Ralf Baechle

MIPS: compat: Fix use of TIF_32BIT_ADDR vs _TIF_32BIT_ADDR

2012-11-09T09:58:18Z

Signed-off-by: Ralf Baechle

Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus

2012-10-18T18:49:39Z

Pull MIPS fixes from Ralf Baechle: "Random small fixes across the MIPS code." * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: MIPS: CMP: Fix physical core number calculation logic MIPS: JZ4740: Forward declare struct uart_port in header. MIPS: JZ4740: Fix '#include guard' in serial.h MIPS: hugetlbfs: Fix hazard between tlb write and pagemask restoration. MIPS: Restore pagemask after dumping the TLB. MIPS: Hugetlbfs: Handle huge pages correctly in pmd_bad() MIPS: R5000: Fix TLB hazard handling. MIPS: tlbex: Deal with re-definition of label MIPS: Make __{,n,u}delay declarations match definitions and generic delay.h

UAPI: Place comments in empty arch Kbuilds to make them non-empty

2012-10-17T11:31:16Z

Place comments in: arch/mips/include/asm/Kbuild arch/tile/include/arch/Kbuild to make them non-empty so that the patch program doesn't remove them when it reduces them to nothing. Possibly they should be just deleted, but it's possible that they'll acquire generic-y or genhdr-y lines in future, so I'm keeping them around for the moment. Note that MIPS will compile happily if the file is deleted instead. I haven't tested TILE, but I suspect it will be the same there. Signed-off-by: David Howells cc: Ralf Baechle cc: Chris Metcalf

MIPS: Hugetlbfs: Handle huge pages correctly in pmd_bad()

2012-10-16T23:01:12Z

Signed-off-by: Ralf Baechle