#include <linux/pci.h>
#include <linux/usb.h>
#include <linux/usb/ehci_def.h>
#include <linux/usb/hcd.h>
#include <asm/xen/hypercall.h>
#include <xen/interface/physdev.h>
#include <xen/xen.h>

static int xen_dbgp_op(struct usb_hcd *hcd, int op)
{
#ifdef CONFIG_PCI
	const struct device *ctrlr = hcd_to_bus(hcd)->controller;
#endif
	struct physdev_dbgp_op dbgp;

	if (!xen_initial_domain())
		return 0;

	dbgp.op = op;

#ifdef CONFIG_PCI
	if (dev_is_pci(ctrlr)) {
		const struct pci_dev *pdev = to_pci_dev(ctrlr);

		dbgp.u.pci.seg = pci_domain_nr(pdev->bus);
		dbgp.u.pci.bus = pdev->bus->number;
		dbgp.u.pci.devfn = pdev->devfn;
		dbgp.bus = PHYSDEVOP_DBGP_BUS_PCI;
	} else
#endif
		dbgp.bus = PHYSDEVOP_DBGP_BUS_UNKNOWN;

	return HYPERVISOR_physdev_op(PHYSDEVOP_dbgp_op, &dbgp);
}

int xen_dbgp_reset_prep(struct usb_hcd *hcd)
{
	return xen_dbgp_op(hcd, PHYSDEVOP_DBGP_RESET_PREPARE);
}

int xen_dbgp_external_startup(struct usb_hcd *hcd)
{
	return xen_dbgp_op(hcd, PHYSDEVOP_DBGP_RESET_DONE);
}

#ifndef CONFIG_EARLY_PRINTK_DBGP
#include <linux/export.h>
EXPORT_SYMBOL_GPL(xen_dbgp_reset_prep);
EXPORT_SYMBOL_GPL(xen_dbgp_external_startup);
#endif
ivate-remove'>nds-private-remove</option>
<option value='packet-loop-back'>packet-loop-back</option>
<option value='packet-rx-pump-back'>packet-rx-pump-back</option>
</select> <input type='submit' value='switch'/></form></td></tr>
<tr><td class='sub'>net-next plumbings</td><td class='sub right'>Tobias Klauser</td></tr></table>
<table class='tabs'><tr><td>
<a href='/cgit.cgi/linux/net-next.git/'>summary</a><a href='/cgit.cgi/linux/net-next.git/refs/?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>refs</a><a href='/cgit.cgi/linux/net-next.git/log/tools/usb'>log</a><a href='/cgit.cgi/linux/net-next.git/tree/tools/usb?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>tree</a><a class='active' href='/cgit.cgi/linux/net-next.git/commit/tools/usb?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>commit</a><a href='/cgit.cgi/linux/net-next.git/diff/tools/usb?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/tools/usb'>
<input type='hidden' name='id' value='91539eb1fda2d530d3b268eef542c5414e54bf1a'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>tools</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/usb?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>usb</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='91539eb1fda2d530d3b268eef542c5414e54bf1a'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Iago Abal &lt;mail@iagoabal.eu&gt;</td><td class='right'>2017-01-11 14:00:21 +0100</td></tr>
<tr><th>committer</th><td>Vinod Koul &lt;vinod.koul@intel.com&gt;</td><td class='right'>2017-01-25 15:35:11 +0530</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/tools/usb?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>91539eb1fda2d530d3b268eef542c5414e54bf1a</a> (<a href='/cgit.cgi/linux/net-next.git/patch/tools/usb?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>960f5ca6342ad20837aff18aad6e8ecd7da32fd6</a> /<a href='/cgit.cgi/linux/net-next.git/tree/tools/usb?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>tools/usb</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/tools/usb?id=6610d0edf6dc7ee97e46ab3a538a565c79d26199'>6610d0edf6dc7ee97e46ab3a538a565c79d26199</a> (<a href='/cgit.cgi/linux/net-next.git/diff/tools/usb?id=91539eb1fda2d530d3b268eef542c5414e54bf1a&amp;id2=6610d0edf6dc7ee97e46ab3a538a565c79d26199'>diff</a>)</td></tr></table>
<div class='commit-subject'>dmaengine: pl330: fix double lock</div><div class='commit-msg'>The static bug finder EBA (http://www.iagoabal.eu/eba/) reported the
following double-lock bug:

    Double lock:
    1. spin_lock_irqsave(pch-&gt;lock, flags) at pl330_free_chan_resources:2236;
    2. call to function `pl330_release_channel' immediately after;
    3. call to function `dma_pl330_rqcb' in line 1753;
    4. spin_lock_irqsave(pch-&gt;lock, flags) at dma_pl330_rqcb:1505.

I have fixed it as suggested by Marek Szyprowski.

First, I have replaced `pch-&gt;lock' with `pl330-&gt;lock' in functions
`pl330_alloc_chan_resources' and `pl330_free_chan_resources'. This avoids
the double-lock by acquiring a different lock than `dma_pl330_rqcb'.

NOTE that, as a result, `pl330_free_chan_resources' executes
`list_splice_tail_init' on `pch-&gt;work_list' under lock `pl330-&gt;lock',
whereas in the rest of the code `pch-&gt;work_list' is protected by
`pch-&gt;lock'. I don't know if this may cause race conditions. Similarly
`pch-&gt;cyclic' is written by `pl330_alloc_chan_resources' under
`pl330-&gt;lock' but read by `pl330_tx_submit' under `pch-&gt;lock'.

Second, I have removed locking from `pl330_request_channel' and
`pl330_release_channel' functions. Function `pl330_request_channel' is
only called from `pl330_alloc_chan_resources', so the lock is already
held. Function `pl330_release_channel' is called from
`pl330_free_chan_resources', which already holds the lock, and from
`pl330_del'. Function `pl330_del' is called in an error path of
`pl330_probe' and at the end of `pl330_remove', but I assume that there
cannot be concurrent accesses to the protected data at those points.

Signed-off-by: Iago Abal &lt;mail@iagoabal.eu&gt;
Reviewed-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Signed-off-by: Vinod Koul &lt;vinod.koul@intel.com&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>Diffstat</a> (limited to 'tools/usb')</div><table summary='diffstat' class='diffstat'>