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| author | Matthew Garrett <matthew.garrett@nebula.com> | 2015-11-16 21:38:40 +0100 |
|---|---|---|
| committer | Darren Hart <dvhart@linux.intel.com> | 2016-01-19 15:49:34 -0800 |
| commit | c1e1655bb892c6800af82c2d88c8063fce7b5c98 (patch) | |
| tree | 5832516de5516f2bf7758344c4e48c7a25073238 /drivers/platform/x86/apple-gmux.c | |
| parent | 65e3cf9c0f05877f76eefcb4f005944dc5379fbf (diff) | |
| download | lwn-c1e1655bb892c6800af82c2d88c8063fce7b5c98.tar.gz lwn-c1e1655bb892c6800af82c2d88c8063fce7b5c98.zip | |
apple-gmux: Assign apple_gmux_data before registering
Registering the handler after both GPUs will trigger a DDC switch for
connector reprobing. This will oops if apple_gmux_data hasn't already
been assigned. Reorder the code to do that.
[Lukas: More generally, this commit fixes a race condition that
is triggered by invoking a handler callback between the call to
vga_switcheroo_register_handler() and the assignment of
apple_gmux_data.]
Tested-by: Pierre Moreau <pierre.morrow@free.fr>
[MBP 5,3 2009 nvidia MCP79 + G96 pre-retina 15"]
Tested-by: Paul Hordiienko <pvt.gord@gmail.com>
[MBP 6,2 2010 intel ILK + nvidia GT216 pre-retina 15"]
Tested-by: Lukas Wunner <lukas@wunner.de>
[MBP 9,1 2012 intel IVB + nvidia GK107 pre-retina 15"]
Tested-by: William Brown <william@blackhats.net.au>
[MBP 8,2 2011 intel SNB + amd turks pre-retina 15"]
Tested-by: Bruno Bierbaumer <bruno@bierbaumer.net>
[MBP 11,3 2013 intel HSW + nvidia GK107 retina 15"]
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Diffstat (limited to 'drivers/platform/x86/apple-gmux.c')
| -rw-r--r-- | drivers/platform/x86/apple-gmux.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c index 976efeb3f2ba..aa58d41ec460 100644 --- a/drivers/platform/x86/apple-gmux.c +++ b/drivers/platform/x86/apple-gmux.c @@ -588,18 +588,20 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) gmux_data->gpe = -1; } + apple_gmux_data = gmux_data; + init_completion(&gmux_data->powerchange_done); + gmux_enable_interrupts(gmux_data); + if (vga_switcheroo_register_handler(&gmux_handler)) { ret = -ENODEV; goto err_register_handler; } - init_completion(&gmux_data->powerchange_done); - apple_gmux_data = gmux_data; - gmux_enable_interrupts(gmux_data); - return 0; err_register_handler: + gmux_disable_interrupts(gmux_data); + apple_gmux_data = NULL; if (gmux_data->gpe >= 0) acpi_disable_gpe(NULL, gmux_data->gpe); err_enable_gpe: |