| Message ID | tencent_6F826F87DF787845466AE67AEFF37E073E08@qq.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Krzysztof Wilczyński |
| Headers | show |
| Series | [v2] PCI: rcar-ep: Fix the issue of the name parameter when calling devm_request_mem_region | expand |
On Sun, Jan 05, 2025 at 01:57:51PM +0800, kingdix10@qq.com wrote: > From: King Dix <kingdix10@qq.com> > > When using devm_request_mem_region to request a resource, if the passed > variable is a stack string variable, it will lead to an oops issue when > eecuting the command cat /proc/iomem. > Is this your observation or you saw the oops? If the latter, please include the relevant log snippet for reference. > Fix this by replacing outbound_name with the name of the previously > requested resource. > > Signed-off-by: King Dix <kingdix10@qq.com> Also, please do not send next version as a reply to the previous one. Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> - Mani > --- > Changes in v2: > - Fix the code indentation issue. > --- > drivers/pci/controller/pcie-rcar-ep.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/pci/controller/pcie-rcar-ep.c b/drivers/pci/controller/pcie-rcar-ep.c > index 047e2cef5afc..c5e0d025bc43 100644 > --- a/drivers/pci/controller/pcie-rcar-ep.c > +++ b/drivers/pci/controller/pcie-rcar-ep.c > @@ -107,7 +107,7 @@ static int rcar_pcie_parse_outbound_ranges(struct rcar_pcie_endpoint *ep, > } > if (!devm_request_mem_region(&pdev->dev, res->start, > resource_size(res), > - outbound_name)) { > + res->name)) { > dev_err(pcie->dev, "Cannot request memory region %s.\n", > outbound_name); > return -EIO; > -- > 2.43.0 >
On Sun, Jan 5, 2025 at 6:03 AM <kingdix10@qq.com> wrote: > > From: King Dix <kingdix10@qq.com> > > When using devm_request_mem_region to request a resource, if the passed > variable is a stack string variable, it will lead to an oops issue when > eecuting the command cat /proc/iomem. > s/eecuting/executing > Fix this by replacing outbound_name with the name of the previously > requested resource. > Fixes: 2a6d0d63d999 ("PCI: rcar: Add endpoint mode support") > Signed-off-by: King Dix <kingdix10@qq.com> > --- > Changes in v2: > - Fix the code indentation issue. > --- > drivers/pci/controller/pcie-rcar-ep.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > With the above fixed, Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Cheers, Prabhakar > diff --git a/drivers/pci/controller/pcie-rcar-ep.c b/drivers/pci/controller/pcie-rcar-ep.c > index 047e2cef5afc..c5e0d025bc43 100644 > --- a/drivers/pci/controller/pcie-rcar-ep.c > +++ b/drivers/pci/controller/pcie-rcar-ep.c > @@ -107,7 +107,7 @@ static int rcar_pcie_parse_outbound_ranges(struct rcar_pcie_endpoint *ep, > } > if (!devm_request_mem_region(&pdev->dev, res->start, > resource_size(res), > - outbound_name)) { > + res->name)) { > dev_err(pcie->dev, "Cannot request memory region %s.\n", > outbound_name); > return -EIO; > -- > 2.43.0 > >
On Sun, 2025-01-05 at 22:23 +0530, Manivannan Sadhasivam wrote: > On Sun, Jan 05, 2025 at 01:57:51PM +0800, kingdix10@qq.com wrote: > > From: King Dix <kingdix10@qq.com> > > > > When using devm_request_mem_region to request a resource, if the > > passed > > variable is a stack string variable, it will lead to an oops issue > > when > > eecuting the command cat /proc/iomem. > > > > Is this your observation or you saw the oops? If the latter, please > include > the relevant log snippet for reference. > > > Fix this by replacing outbound_name with the name of the previously > > requested resource. > > > > Signed-off-by: King Dix <kingdix10@qq.com> > > Also, please do not send next version as a reply to the previous one. > > Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> > > - Mani > > > --- > > Changes in v2: > > - Fix the code indentation issue. > > --- > > drivers/pci/controller/pcie-rcar-ep.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/pci/controller/pcie-rcar-ep.c > > b/drivers/pci/controller/pcie-rcar-ep.c > > index 047e2cef5afc..c5e0d025bc43 100644 > > --- a/drivers/pci/controller/pcie-rcar-ep.c > > +++ b/drivers/pci/controller/pcie-rcar-ep.c > > @@ -107,7 +107,7 @@ static int > > rcar_pcie_parse_outbound_ranges(struct rcar_pcie_endpoint *ep, > > } > > if (!devm_request_mem_region(&pdev->dev, res->start, > > resource_size(res), > > - outbound_name)) { > > + res->name)) { > > dev_err(pcie->dev, "Cannot request memory region %s.\n", > > outbound_name); > > return -EIO; > > -- > > 2.43.0 > > > This is only a potential issue that I found while analyzing the code. When cat /proc/iomem is executed, the r_show function called, it will access the name parameter of resource. Specifically, if a variable on the stack is used when calling devm_request_mem_region, it will lead to an oops problem.
diff --git a/drivers/pci/controller/pcie-rcar-ep.c b/drivers/pci/controller/pcie-rcar-ep.c index 047e2cef5afc..c5e0d025bc43 100644 --- a/drivers/pci/controller/pcie-rcar-ep.c +++ b/drivers/pci/controller/pcie-rcar-ep.c @@ -107,7 +107,7 @@ static int rcar_pcie_parse_outbound_ranges(struct rcar_pcie_endpoint *ep, } if (!devm_request_mem_region(&pdev->dev, res->start, resource_size(res), - outbound_name)) { + res->name)) { dev_err(pcie->dev, "Cannot request memory region %s.\n", outbound_name); return -EIO;