Fix AIO and 4G-4G hang
PATCH 1/1 Fix AIO and 4G-4G hang
This patch appears to fix the hangs seen with AIO and 4G-4G for me. It ensures that the indirect versions of copy_xxx_user are used during aio retries running in worker thread context (i.e. access aio issuer's user-space instead of kernel-space).
Regards
Suparna
Signature · 35 lines
Suparna Bhattacharya ([email protected]) Linux Technology Center IBM Software Labs, India ------------------------------------------------------- diffstat aio-4g4g-fix.patch aio.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletion(-) --- 260t5mm2/fs/aio.c Fri Sep 19 15:15:39 2003 +++ linux-2.6.0-test5-mm4/fs/aio.c Tue Oct 7 23:40:22 2003 @@ -805,18 +814,23 @@ static inline void aio_run_iocbs(struct * aio_kick_handler: * Work queue handler triggered to process pending * retries on an ioctx. Takes on the aio issuer's - * mm context before running the iocbs. + * mm context before running the iocbs, so that + * copy_xxx_user operates on the issuer's address + * space. * Run on aiod's context. */ static void aio_kick_handler(void *data) { struct kioctx *ctx = data; + mm_segment_t oldfs = get_fs(); + set_fs(USER_DS); use_mm(ctx->mm); spin_lock_irq(&ctx->ctx_lock); __aio_run_iocbs(ctx); unuse_mm(ctx->mm); spin_unlock_irq(&ctx->ctx_lock); + set_fs(oldfs); }