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    Subject[PATCH 10/22] spufs: fix missing stop-and-signal
    From: Masato Noguchi <Masato.Noguchi@jp.sony.com>

    When there is pending signals, current spufs_run_spu() always returns
    -ERESTARTSYS and it is called again automatically.
    But, if spe already stopped by stop-and-signal or halt instruction,
    returning -ERESTARTSYS makes stop-and-signal/halt lost and
    spu run over the end-point.

    For your convenience, I attached a sample code to restage this bug.
    If there is no bug, printed NPC will be 0x4000.

    Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
    Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>

    ---

    run.c | 28 ++++++++++++++++++----------
    1 files changed, 18 insertions(+), 10 deletions(-)


    Index: linux-2.6/arch/powerpc/platforms/cell/spufs/run.c
    ===================================================================
    --- linux-2.6.orig/arch/powerpc/platforms/cell/spufs/run.c
    +++ linux-2.6/arch/powerpc/platforms/cell/spufs/run.c
    @@ -79,13 +79,7 @@ static inline int spu_run_fini(struct sp

    if (signal_pending(current))
    ret = -ERESTARTSYS;
    - if (unlikely(current->ptrace & PT_PTRACED)) {
    - if ((*status & SPU_STATUS_STOPPED_BY_STOP)
    - && (*status >> SPU_STOP_STATUS_SHIFT) == 0x3fff) {
    - force_sig(SIGTRAP, current);
    - ret = -ERESTARTSYS;
    - }
    - }
    +
    return ret;
    }

    @@ -232,7 +226,7 @@ long spufs_run_spu(struct file *file, st
    if (unlikely(ctx->state != SPU_STATE_RUNNABLE)) {
    ret = spu_reacquire_runnable(ctx, npc, &status);
    if (ret)
    - goto out;
    + goto out2;
    continue;
    }
    ret = spu_process_events(ctx);
    @@ -242,10 +236,24 @@ long spufs_run_spu(struct file *file, st

    ctx->ops->runcntl_stop(ctx);
    ret = spu_run_fini(ctx, npc, &status);
    - if (!ret)
    - ret = status;
    spu_yield(ctx);

    +out2:
    + if ((ret == 0) ||
    + ((ret == -ERESTARTSYS) &&
    + ((status & SPU_STATUS_STOPPED_BY_HALT) ||
    + ((status & SPU_STATUS_STOPPED_BY_STOP) &&
    + (status >> SPU_STOP_STATUS_SHIFT != 0x2104)))))
    + ret = status;
    +
    + if (unlikely(current->ptrace & PT_PTRACED)) {
    + if ((status & SPU_STATUS_STOPPED_BY_STOP)
    + && (status >> SPU_STOP_STATUS_SHIFT) == 0x3fff) {
    + force_sig(SIGTRAP, current);
    + ret = -ERESTARTSYS;
    + }
    + }
    +
    out:
    *event = ctx->event_return;
    up(&ctx->run_sema);
    --

    -
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