| Message ID | 20161215051241.20815-1-ruscur@russell.cc (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Dec 15, 2016 at 3:42 PM, Russell Currey <ruscur@russell.cc> wrote: > ast_get_dram_info() configures a window in order to access BMC memory. > A BMC register can be configured to disallow this, and if so, causes > an infinite loop in the ast driver which renders the system unusable. > > Fix this by erroring out if an error is detected. On powerpc systems with > EEH, this leads to the device being fenced and the system continuing to > operate. > > Cc: <stable@vger.kernel.org> # 3.10+ > Signed-off-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Joel Stanley <joel@jms.id.au> Thanks Russel. Cheers, Joel > --- > drivers/gpu/drm/ast/ast_main.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c > index 904beaa..f75c642 100644 > --- a/drivers/gpu/drm/ast/ast_main.c > +++ b/drivers/gpu/drm/ast/ast_main.c > @@ -223,7 +223,8 @@ static int ast_get_dram_info(struct drm_device *dev) > ast_write32(ast, 0x10000, 0xfc600309); > > do { > - ; > + if (pci_channel_offline(dev->pdev)) > + return -EIO; > } while (ast_read32(ast, 0x10000) != 0x01); > data = ast_read32(ast, 0x10004); > > @@ -428,7 +429,9 @@ int ast_driver_load(struct drm_device *dev, unsigned long flags) > ast_detect_chip(dev, &need_post); > > if (ast->chip != AST1180) { > - ast_get_dram_info(dev); > + ret = ast_get_dram_info(dev); > + if (ret) > + goto out_free; > ast->vram_size = ast_get_vram_info(dev); > DRM_INFO("dram %d %d %d %08x\n", ast->mclk, ast->dram_type, ast->dram_bus_width, ast->vram_size); > }
On Fri, Dec 16, 2016 at 11:38:57AM +1030, Joel Stanley wrote: > On Thu, Dec 15, 2016 at 3:42 PM, Russell Currey <ruscur@russell.cc> wrote: > > ast_get_dram_info() configures a window in order to access BMC memory. > > A BMC register can be configured to disallow this, and if so, causes > > an infinite loop in the ast driver which renders the system unusable. > > > > Fix this by erroring out if an error is detected. On powerpc systems with > > EEH, this leads to the device being fenced and the system continuing to > > operate. > > > > Cc: <stable@vger.kernel.org> # 3.10+ > > Signed-off-by: Russell Currey <ruscur@russell.cc> > > Reviewed-by: Joel Stanley <joel@jms.id.au> Applied to drm-misc-fixes. -Daniel > > Thanks Russel. > > Cheers, > > Joel > > > > --- > > drivers/gpu/drm/ast/ast_main.c | 7 +++++-- > > 1 file changed, 5 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c > > index 904beaa..f75c642 100644 > > --- a/drivers/gpu/drm/ast/ast_main.c > > +++ b/drivers/gpu/drm/ast/ast_main.c > > @@ -223,7 +223,8 @@ static int ast_get_dram_info(struct drm_device *dev) > > ast_write32(ast, 0x10000, 0xfc600309); > > > > do { > > - ; > > + if (pci_channel_offline(dev->pdev)) > > + return -EIO; > > } while (ast_read32(ast, 0x10000) != 0x01); > > data = ast_read32(ast, 0x10004); > > > > @@ -428,7 +429,9 @@ int ast_driver_load(struct drm_device *dev, unsigned long flags) > > ast_detect_chip(dev, &need_post); > > > > if (ast->chip != AST1180) { > > - ast_get_dram_info(dev); > > + ret = ast_get_dram_info(dev); > > + if (ret) > > + goto out_free; > > ast->vram_size = ast_get_vram_info(dev); > > DRM_INFO("dram %d %d %d %08x\n", ast->mclk, ast->dram_type, ast->dram_bus_width, ast->vram_size); > > } > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c index 904beaa..f75c642 100644 --- a/drivers/gpu/drm/ast/ast_main.c +++ b/drivers/gpu/drm/ast/ast_main.c @@ -223,7 +223,8 @@ static int ast_get_dram_info(struct drm_device *dev) ast_write32(ast, 0x10000, 0xfc600309); do { - ; + if (pci_channel_offline(dev->pdev)) + return -EIO; } while (ast_read32(ast, 0x10000) != 0x01); data = ast_read32(ast, 0x10004); @@ -428,7 +429,9 @@ int ast_driver_load(struct drm_device *dev, unsigned long flags) ast_detect_chip(dev, &need_post); if (ast->chip != AST1180) { - ast_get_dram_info(dev); + ret = ast_get_dram_info(dev); + if (ret) + goto out_free; ast->vram_size = ast_get_vram_info(dev); DRM_INFO("dram %d %d %d %08x\n", ast->mclk, ast->dram_type, ast->dram_bus_width, ast->vram_size); }
ast_get_dram_info() configures a window in order to access BMC memory. A BMC register can be configured to disallow this, and if so, causes an infinite loop in the ast driver which renders the system unusable. Fix this by erroring out if an error is detected. On powerpc systems with EEH, this leads to the device being fenced and the system continuing to operate. Cc: <stable@vger.kernel.org> # 3.10+ Signed-off-by: Russell Currey <ruscur@russell.cc> --- drivers/gpu/drm/ast/ast_main.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)