ipmi_si: Fix crash when using hard-coded device

When excuting a command like:
  modprobe ipmi_si ports=0xffc0e3 type=bt
The system would get an oops.

The trouble here is that ipmi_si_hardcode_find_bmc() is called before
ipmi_si_platform_init(), but initialization of the hard-coded device
creates an IPMI platform device, which won't be initialized yet.

The real trouble is that hard-coded devices aren't created with
any device, and the fixup is done later.  So do it right, create the
hard-coded devices as normal platform devices.

This required adding some new resource types to the IPMI platform
code for passing information required by the hard-coded device
and adding some code to remove the hard-coded platform devices
on module removal.

To enforce the "hard-coded devices passed by the user take priority
over firmware devices" rule, some special code was added to check
and see if a hard-coded device already exists.

Reported-by: Yang Yingliang <yangyingliang@huawei.com>
Cc: stable@vger.kernel.org # v4.15+
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Tested-by: Yang Yingliang <yangyingliang@huawei.com>

1 files changed, 22 insertions, 7 deletions

diff --git a/drivers/char/ipmi/ipmi_si_platform.c b/drivers/char/ipmi/ipmi_si_platform.c
index 15cf819f884f..8158d03542f4 100644
--- a/drivers/char/ipmi/ipmi_si_platform.c
+++ b/drivers/char/ipmi/ipmi_si_platform.c
@@ -128,8 +128,6 @@ ipmi_get_info_from_resources(struct platform_device *pdev,
 		if (res_second->start > io->addr_data)
 			io->regspacing = res_second->start - io->addr_data;
 	}
-	io->regsize = DEFAULT_REGSIZE;
-	io->regshift = 0;
 
 	return res;
 }
@@ -137,7 +135,7 @@ ipmi_get_info_from_resources(struct platform_device *pdev,
 static int platform_ipmi_probe(struct platform_device *pdev)
 {
 	struct si_sm_io io;
-	u8 type, slave_addr, addr_source;
+	u8 type, slave_addr, addr_source, regsize, regshift;
 	int rv;
 
 	rv = device_property_read_u8(&pdev->dev, "addr-source", &addr_source);
@@ -149,7 +147,7 @@ static int platform_ipmi_probe(struct platform_device *pdev)
 	if (addr_source == SI_SMBIOS) {
 		if (!si_trydmi)
 			return -ENODEV;
-	} else {
+	} else if (addr_source != SI_HARDCODED) {
 		if (!si_tryplatform)
 			return -ENODEV;
 	}
@@ -169,11 +167,23 @@ static int platform_ipmi_probe(struct platform_device *pdev)
 	case SI_BT:
 		io.si_type = type;
 		break;
+	case SI_TYPE_INVALID: /* User disabled this in hardcode. */
+		return -ENODEV;
 	default:
 		dev_err(&pdev->dev, "ipmi-type property is invalid\n");
 		return -EINVAL;
 	}
 
+	io.regsize = DEFAULT_REGSIZE;
+	rv = device_property_read_u8(&pdev->dev, "reg-size", &regsize);
+	if (!rv)
+		io.regsize = regsize;
+
+	io.regshift = 0;
+	rv = device_property_read_u8(&pdev->dev, "reg-shift", &regshift);
+	if (!rv)
+		io.regshift = regshift;
+
 	if (!ipmi_get_info_from_resources(pdev, &io))
 		return -EINVAL;
 
@@ -193,7 +203,8 @@ static int platform_ipmi_probe(struct platform_device *pdev)
 
 	io.dev = &pdev->dev;
 
-	pr_info("ipmi_si: SMBIOS: %s %#lx regsize %d spacing %d irq %d\n",
+	pr_info("ipmi_si: %s: %s %#lx regsize %d spacing %d irq %d\n",
+		ipmi_addr_src_to_str(addr_source),
 		(io.addr_type == IPMI_IO_ADDR_SPACE) ? "io" : "mem",
 		io.addr_data, io.regsize, io.regspacing, io.irq);
 
@@ -358,6 +369,9 @@ static int acpi_ipmi_probe(struct platform_device *pdev)
 		goto err_free;
 	}
 
+	io.regsize = DEFAULT_REGSIZE;
+	io.regshift = 0;
+
 	res = ipmi_get_info_from_resources(pdev, &io);
 	if (!res) {
 		rv = -EINVAL;
@@ -420,8 +434,9 @@ static int ipmi_remove(struct platform_device *pdev)
 }
 
 static const struct platform_device_id si_plat_ids[] = {
-    { "dmi-ipmi-si", 0 },
-    { }
+	{ "dmi-ipmi-si", 0 },
+	{ "hardcode-ipmi-si", 0 },
+	{ }
 };
 
 struct platform_driver ipmi_platform_driver = {