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  1. 21 Apr, 2017 1 commit
  3. 20 Apr, 2017 2 commits
    • Nicholas Piggin's avatar
      powerpc/64s: Use relon prolog for EXC_VIRT_OOL_MASKABLE_HV handlers · a050d20d
      Nicholas Piggin authored 
      Hypervisor Virtualization and Directed Hypervisor Doorbell interrupt handlers
use the macro EXC_VIRT_OOL_MASKABLE_HV for their relocation-on handlers, which
calls MASKABLE_RELON_EXCEPTION_HV_OOL, which uses the *real mode* interrupt
prolog. This means we needlessly rfid from virtual mode to virtual mode.

For POWER8 it only affects doorbell IPIs. Context switch microbenchmark between
threads with snooze disabled (which causes IPI) gets about 3% faster, about 370
cycles. Should be more important on POWER9 with global doorbells and HVI for
host interrupts.

Use the RELON variant instead to reduce overhead.

Fixes: 1707dd16 ("powerpc: Save CFAR before branching in interrupt entry paths")
Signed-off-by: default avatarNicholas Piggin <npiggin@gmail.com>
[mpe: Fold some more detail into the change log]
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      a050d20d
    • Michael Ellerman's avatar
      powerpc/xive: Fix missing check of rc != OPAL_BUSY · 686978b1
      Michael Ellerman authored 
      Dan Carpenter noticed that the code in __xive_native_disable_queue() has a for
loop with an unconditional break in the middle, which doesn't make a lot of
sense.

What the code's supposed to do is loop as long as OPAL says it's busy, if we get
any other return code, either success or failure, then we should break the loop.

So add the missing check.

Fixes: 243e2511 ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      686978b1
  5. 19 Apr, 2017 14 commits
  7. 13 Apr, 2017 18 commits
  9. 12 Apr, 2017 5 commits
    • Rashmica Gupta's avatar
      powerpc/mm: Fix hash table dump when memory is not contiguous · 9e4114b3
      Rashmica Gupta authored 
      The current behaviour of the hash table dump assumes that memory is contiguous
and iterates from the start of memory to (start + size of memory). When memory
isn't physically contiguous, this doesn't work.

If memory exists at 0-5 GB and 6-10 GB then the current approach will check if
entries exist in the hash table from 0GB to 9GB. This patch changes the
behaviour to iterate over any holes up to the end of memory.

Fixes: 1515ab93 ("powerpc/mm: Dump hash table")
Signed-off-by: default avatarRashmica Gupta <rashmica.g@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      9e4114b3
    • Oliver O'Halloran's avatar
      powerpc/mm: Add physical address to Linux page table dump · aaa22952
      Oliver O'Halloran authored 
      The current page table dumper scans the Linux page tables and coalesces mappings
with adjacent virtual addresses and similar PTE flags. This behaviour is
somewhat broken when you consider the IOREMAP space where entirely unrelated
mappings will appear to be virtually contiguous. This patch modifies the range
coalescing so that only ranges that are both physically and virtually contiguous
are combined. This patch also adds to the dump output the physical address at
the start of each range.

Fixes: 8eb07b18 ("powerpc/mm: Dump linux pagetables")
Signed-off-by: default avatarOliver O'Halloran <oohall@gmail.com>
[mpe: Print the physicall address with 0x like the other addresses]
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      aaa22952
    • Oliver O'Halloran's avatar
      powerpc/mm: Fix missing _PAGE_NON_IDEMPOTENT in pgtable dump · 70538eaa
      Oliver O'Halloran authored 
      On Book3s we have two PTE flags used to mark cache-inhibited mappings:
_PAGE_TOLERANT and _PAGE_NON_IDEMPOTENT. Currently the kernel page table dumper
only looks at the generic _PAGE_NO_CACHE which is defined to be _PAGE_TOLERANT.
This patch modifies the dumper so both flags are shown in the dump.

Fixes: 8eb07b18 ("powerpc/mm: Dump linux pagetables")
Signed-off-by: default avatarOliver O'Halloran <oohall@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      70538eaa
    • Balbir Singh's avatar
      powerpc/tracing: Allow tracing of mmap syscalls · 9c355917
      Balbir Singh authored 
      Currently sys_mmap() and sys_mmap2() (32-bit only), are not visible to the
syscall tracing machinery. This means users are not able to see the execution of
mmap() syscalls using the syscall tracer.

Fix that by using SYSCALL_DEFINE6 for sys_mmap() and sys_mmap2() so that the
meta-data associated with these syscalls is visible to the syscall tracer.

A side-effect of this change is that the return type has changed from unsigned
long to long. However this should have no effect, the only code in the kernel
which uses the result of these syscalls is in the syscall return path, which is
written in asm and treats the result as unsigned regardless.

Example output:
  cat-3399  [001] ....   196.542410: sys_mmap(addr: 7fff922a0000, len: 20000, prot: 3, flags: 812, fd: 3, offset: 1b0000)
  cat-3399  [001] ....   196.542443: sys_mmap -> 0x7fff922a0000
  cat-3399  [001] ....   196.542668: sys_munmap(addr: 7fff922c0000, len: 6d2c)
  cat-3399  [001] ....   196.542677: sys_munmap -> 0x0
Signed-off-by: default avatarBalbir Singh <bsingharora@gmail.com>
[mpe: Massage change log, add detail on return type change]
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      9c355917
    • Michael Ellerman's avatar
      powerpc/mm: Fix swapper_pg_dir size on 64-bit hash w/64K pages · 03dfee6d
      Michael Ellerman authored 
      Recently in commit f6eedbba ("powerpc/mm/hash: Increase VA range to 128TB"),
we increased H_PGD_INDEX_SIZE to 15 when we're building with 64K pages. This
makes it larger than RADIX_PGD_INDEX_SIZE (13), which means the logic to
calculate MAX_PGD_INDEX_SIZE in book3s/64/pgtable.h is wrong.

The end result is that the PGD (Page Global Directory, ie top level page table)
of the kernel (aka. swapper_pg_dir), is too small.

This generally doesn't lead to a crash, as we don't use the full range in normal
operation. However if we try to dump the kernel pagetables we can trigger a
crash because we walk off the end of the pgd into other memory and eventually
try to dereference something bogus:

  $ cat /sys/kernel/debug/kernel_pagetables
  Unable to handle kernel paging request for data at address 0xe8fece0000000000
  Faulting instruction address: 0xc000000000072314
  cpu 0xc: Vector: 380 (Data SLB Access) at [c0000000daa13890]
      pc: c000000000072314: ptdump_show+0x164/0x430
      lr: c000000000072550: ptdump_show+0x3a0/0x430
     dar: e802cf0000000000
  seq_read+0xf8/0x560
  full_proxy_read+0x84/0xc0
  __vfs_read+0x6c/0x1d0
  vfs_read+0xbc/0x1b0
  SyS_read+0x6c/0x110
  system_call+0x38/0xfc

The root cause is that MAX_PGD_INDEX_SIZE isn't actually computed to be
the max of H_PGD_INDEX_SIZE or RADIX_PGD_INDEX_SIZE. To fix that move
the calculation into asm-offsets.c where we can do it easily using
max().

Fixes: f6eedbba ("powerpc/mm/hash: Increase VA range to 128TB")
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      03dfee6d
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