Re: [mnyman-xhci:for-usb-next 9/10] drivers/usb/host/xhci-ring.c:1405 xhci_handle_cmd_set_deq() error: uninitialized symbol 'stream_ctx'.

[Mathias Nyman <mathias.nyman@linux.intel.com>]

On 25.9.2024 17.31, Dan Carpenter wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/mnyman/xhci.git for-usb-next
> head:   645eb2ce6b3e541d3c651f136da8a16f76799526
> commit: fdd9a29e9139a8988b65dce295dfc3f089003ae0 [9/10] xhci: trace stream context at Set TR Deq command completion
> config: powerpc64-randconfig-r072-20240925 (https://download.01.org/0day-ci/archive/20240925/202409252250.WNZonX5o-lkp@intel.com/config)
> compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 7773243d9916f98ba0ffce0c3a960e4aa9f03e81)
> 

> fdd9a29e9139a8 Mathias Nyman    2024-09-12  1364  	if (ep->ep_state & EP_HAS_STREAMS && ep->stream_info) {
> 
> stream_ctx is only initialized when ep->stream_info is non-NULL.
> Could we change this condition to:
> 	if ((ep->ep_state & EP_HAS_STREAMS) && cmd_comp_code == COMP_SUCCESS) {
> instead?

Thanks, this would work, but I'd like to keep the trace message below in cases
where the ep->stream_info is valid but command is not successful.

> 
> fdd9a29e9139a8 Mathias Nyman    2024-09-12  1365  		stream_ctx = &ep->stream_info->stream_ctx_array[stream_id];
> fdd9a29e9139a8 Mathias Nyman    2024-09-12  1366  		trace_xhci_handle_cmd_set_deq_stream(ep->stream_info, stream_id);
> fdd9a29e9139a8 Mathias Nyman    2024-09-12  1367  	}
> fdd9a29e9139a8 Mathias Nyman    2024-09-12  1368
> c69a059783b241 Xenia Ragiadakou 2013-09-09  1369  	if (cmd_comp_code != COMP_SUCCESS) {
> ae636747146ea9 Sarah Sharp      2009-04-29  1370  		unsigned int ep_state;
> ae636747146ea9 Sarah Sharp      2009-04-29  1371  		unsigned int slot_state;

...

> ae636747146ea9 Sarah Sharp      2009-04-29  1400  		 */
> ae636747146ea9 Sarah Sharp      2009-04-29  1401  	} else {
> 9aad95e292f58d Hans de Goede    2013-10-04  1402  		u64 deq;
> 9aad95e292f58d Hans de Goede    2013-10-04  1403  		/* 4.6.10 deq ptr is written to the stream ctx for streams */
> 9aad95e292f58d Hans de Goede    2013-10-04  1404  		if (ep->ep_state & EP_HAS_STREAMS) {
> fdd9a29e9139a8 Mathias Nyman    2024-09-12 @1405  			deq = le64_to_cpu(stream_ctx->stream_ring) & SCTX_DEQ_MASK;
>                                                                                            ^^^^^^^^^^
> Warning.  My guess is that if cmd_comp_code is success then ep->stream_info but
> it's hard to tell without more context...

Most likely yes if endpoint has streams.

I'll fix this

Thanks
Mathias