[PATCH 0/6] scsi: fixes for building with LTO

[PATCH 0/6] scsi: fixes for building with LTO

[Arnd Bergmann]

I experimented with link time optimization after Nico's
article at https://lwn.net/Articles/744507/

Here is a set of patches that came out of it for the scsi
subsystem.

Arnd Bergmann (6):
  scsi: fc_encode: work around strncpy size warnings
  scsi: NCR53c406a: avoid section mismatch with LTO
  scsi: sym53c416: avoid section mismatch with LTO
  scsi: qedf: fix LTO-enabled build
  scsi: qedi: fix building with LTO
  scsi: qedf: use correct strncpy() size

 drivers/scsi/NCR53c406a.c        |  2 +-
 drivers/scsi/qedf/qedf_dbg.c     |  2 +-
 drivers/scsi/qedf/qedf_dbg.h     | 17 ++++++++++-------
 drivers/scsi/qedf/qedf_debugfs.c |  6 +++---
 drivers/scsi/qedf/qedf_main.c    |  8 +++-----
 drivers/scsi/qedi/qedi_dbg.h     |  2 +-
 drivers/scsi/qedi/qedi_debugfs.c |  4 ++--
 drivers/scsi/qedi/qedi_gbl.h     |  4 ++--
 drivers/scsi/qedi/qedi_main.c    |  4 ++--
 drivers/scsi/sym53c416.c         |  2 +-
 include/scsi/fc/fc_ms.h          |  2 +-
 11 files changed, 27 insertions(+), 26 deletions(-)

-- 
2.9.0

[PATCH 1/6] scsi: fc_encode: work around strncpy size warnings

[Arnd Bergmann]

struct fc_fdmi_attr_entry contains a variable-length string at
the end, which is encoded as a one-byte array.  gcc-8 notices that
we copy strings into it that obviously go beyond that one byte:

In function 'fc_ct_ms_fill',
    inlined from 'fc_elsct_send' at include/scsi/fc_encode.h:518:8:
include/scsi/fc_encode.h:275:3: error: 'strncpy' writing 64 bytes into a region of size 1 overflows the destination [-Werror=stringop-overflow=]
   strncpy((char *)&entry->value,
   ^
include/scsi/fc_encode.h:287:3: error: 'strncpy' writing 64 bytes into a region of size 1 overflows the destination [-Werror=stringop-overflow=]
   strncpy((char *)&entry->value,
   ^

No idea what the right fix is.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 include/scsi/fc/fc_ms.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/scsi/fc/fc_ms.h b/include/scsi/fc/fc_ms.h
index f52b921b5c70..c5614e725a0e 100644
--- a/include/scsi/fc/fc_ms.h
+++ b/include/scsi/fc/fc_ms.h
@@ -128,7 +128,7 @@ struct fc_fdmi_port_name {
 struct fc_fdmi_attr_entry {
 	__be16		type;
 	__be16		len;
-	__u8		value[1];
+	__u8		value[];
 } __attribute__((__packed__));
 
 /*
-- 
2.9.0

[PATCH 2/6] scsi: NCR53c406a: avoid section mismatch with LTO

[Arnd Bergmann]

Building with link time optimizations produces a false-postive section
mismatch warning:

WARNING: vmlinux.o(.data+0xf7e8): Section mismatch in reference from the variable driver_template.lto_priv.6914 to the function .init.text:NCR53c406a_detect()
The variable driver_template.lto_priv.6914 references
the function __init NCR53c406a_detect()
If the reference is valid then annotate the
variable with __init* or __refdata (see linux/init.h) or name the variable:
*_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console

The ->detect callback is always entered from the init_this_scsi_driver()
init function, but apparently LTO turns the optimized direct function
call into an indirect call through a non-__initdata pointer.

All drivers using init_this_scsi_driver() are for ancient hardware,
and most don't mark the detect() callback as __init(), so I'm
just removing the annotation here to kill off the warning instead
of doing a larger rework.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/scsi/NCR53c406a.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/NCR53c406a.c b/drivers/scsi/NCR53c406a.c
index 6e110c630d2c..44b09870bf51 100644
--- a/drivers/scsi/NCR53c406a.c
+++ b/drivers/scsi/NCR53c406a.c
@@ -448,7 +448,7 @@ static __inline__ int NCR53c406a_pio_write(unsigned char *request, unsigned int
 }
 #endif				/* USE_PIO */
 
-static int __init NCR53c406a_detect(struct scsi_host_template * tpnt)
+static int NCR53c406a_detect(struct scsi_host_template * tpnt)
 {
 	int present = 0;
 	struct Scsi_Host *shpnt = NULL;
-- 
2.9.0

[PATCH 3/6] scsi: sym53c416: avoid section mismatch with LTO

[Arnd Bergmann]

Building with link time optimizations produces a false-postive section
mismatch warning:

WARNING: vmlinux.o(.data+0xf8c8): Section mismatch in reference from the variable driver_template.lto_priv.6915 to the function .init.text:sym53c416_detect()
The variable driver_template.lto_priv.6915 references
the function __init sym53c416_detect()
If the reference is valid then annotate the
variable with __init* or __refdata (see linux/init.h) or name the variable:
*_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console

The ->detect callback is always entered from the init_this_scsi_driver()
init function, but apparently LTO turns the optimized direct function
call into an indirect call through a non-__initdata pointer.

All drivers using init_this_scsi_driver() are for ancient hardware,
and most don't mark the detect() callback as __init(), so I'm
just removing the annotation here to kill off the warning instead
of doing a larger rework.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/scsi/sym53c416.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/sym53c416.c b/drivers/scsi/sym53c416.c
index 5bdcbe8fa958..e68bcdc75bc3 100644
--- a/drivers/scsi/sym53c416.c
+++ b/drivers/scsi/sym53c416.c
@@ -608,7 +608,7 @@ static void sym53c416_probe(void)
 	}
 }
 
-int __init sym53c416_detect(struct scsi_host_template *tpnt)
+int sym53c416_detect(struct scsi_host_template *tpnt)
 {
 	unsigned long flags;
 	struct Scsi_Host * shpnt = NULL;
-- 
2.9.0

[PATCH 4/6] scsi: qedf: fix LTO-enabled build

[Arnd Bergmann]

The prototype for qedf_dbg_fops/qedf_debugfs_ops doesn't match the definition,
which causes the final link to fail with link-time optimizations:

drivers/scsi/qedf/qedf_main.c:34: error: type of 'qedf_dbg_fops' does not match original declaration [-Werror=lto-type-mismatch]
 extern struct file_operations qedf_dbg_fops;

drivers/scsi/qedf/qedf_debugfs.c:443: note: 'qedf_dbg_fops' was previously declared here
 const struct file_operations qedf_dbg_fops[] = {

drivers/scsi/qedf/qedf_main.c:33: error: type of 'qedf_debugfs_ops' does not match original declaration [-Werror=lto-type-mismatch]
 extern struct qedf_debugfs_ops qedf_debugfs_ops;

drivers/scsi/qedf/qedf_debugfs.c:102: note: 'qedf_debugfs_ops' was previously declared here
 struct qedf_debugfs_ops qedf_debugfs_ops[] = {

This corrects the prototype and moves it into a shared header file where it
belongs. The file operations can also be marked 'const' like the
qedf_debugfs_ops.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/scsi/qedf/qedf_dbg.h     | 17 ++++++++++-------
 drivers/scsi/qedf/qedf_debugfs.c |  6 +++---
 drivers/scsi/qedf/qedf_main.c    |  8 +++-----
 3 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/drivers/scsi/qedf/qedf_dbg.h b/drivers/scsi/qedf/qedf_dbg.h
index 50083cae84c3..77c27e888969 100644
--- a/drivers/scsi/qedf/qedf_dbg.h
+++ b/drivers/scsi/qedf/qedf_dbg.h
@@ -116,6 +116,14 @@ extern int qedf_create_sysfs_attr(struct Scsi_Host *shost,
 extern void qedf_remove_sysfs_attr(struct Scsi_Host *shost,
 				    struct sysfs_bin_attrs *iter);
 
+struct qedf_debugfs_ops {
+	char *name;
+	struct qedf_list_of_funcs *qedf_funcs;
+};
+
+extern const struct qedf_debugfs_ops qedf_debugfs_ops[];
+extern const struct file_operations qedf_dbg_fops[];
+
 #ifdef CONFIG_DEBUG_FS
 /* DebugFS related code */
 struct qedf_list_of_funcs {
@@ -123,11 +131,6 @@ struct qedf_list_of_funcs {
 	ssize_t (*oper_func)(struct qedf_dbg_ctx *qedf);
 };
 
-struct qedf_debugfs_ops {
-	char *name;
-	struct qedf_list_of_funcs *qedf_funcs;
-};
-
 #define qedf_dbg_fileops(drv, ops) \
 { \
 	.owner  = THIS_MODULE, \
@@ -147,8 +150,8 @@ struct qedf_debugfs_ops {
 }
 
 extern void qedf_dbg_host_init(struct qedf_dbg_ctx *qedf,
-				struct qedf_debugfs_ops *dops,
-				struct file_operations *fops);
+				const struct qedf_debugfs_ops *dops,
+				const struct file_operations *fops);
 extern void qedf_dbg_host_exit(struct qedf_dbg_ctx *qedf);
 extern void qedf_dbg_init(char *drv_name);
 extern void qedf_dbg_exit(void);
diff --git a/drivers/scsi/qedf/qedf_debugfs.c b/drivers/scsi/qedf/qedf_debugfs.c
index 2b1ef3075e93..c539a7ae3a7e 100644
--- a/drivers/scsi/qedf/qedf_debugfs.c
+++ b/drivers/scsi/qedf/qedf_debugfs.c
@@ -23,8 +23,8 @@ static struct dentry *qedf_dbg_root;
  **/
 void
 qedf_dbg_host_init(struct qedf_dbg_ctx *qedf,
-		    struct qedf_debugfs_ops *dops,
-		    struct file_operations *fops)
+		    const struct qedf_debugfs_ops *dops,
+		    const struct file_operations *fops)
 {
 	char host_dirname[32];
 	struct dentry *file_dentry = NULL;
@@ -99,7 +99,7 @@ qedf_dbg_exit(void)
 	qedf_dbg_root = NULL;
 }
 
-struct qedf_debugfs_ops qedf_debugfs_ops[] = {
+const struct qedf_debugfs_ops qedf_debugfs_ops[] = {
 	{ "fp_int", NULL },
 	{ "io_trace", NULL },
 	{ "debug", NULL },
diff --git a/drivers/scsi/qedf/qedf_main.c b/drivers/scsi/qedf/qedf_main.c
index ccd9a08ea030..284ccb566b19 100644
--- a/drivers/scsi/qedf/qedf_main.c
+++ b/drivers/scsi/qedf/qedf_main.c
@@ -23,6 +23,7 @@
 #include <linux/if_vlan.h>
 #include <linux/cpu.h>
 #include "qedf.h"
+#include "qedf_dbg.h"
 #include <uapi/linux/pci_regs.h>
 
 const struct qed_fcoe_ops *qed_ops;
@@ -30,9 +31,6 @@ const struct qed_fcoe_ops *qed_ops;
 static int qedf_probe(struct pci_dev *pdev, const struct pci_device_id *id);
 static void qedf_remove(struct pci_dev *pdev);
 
-extern struct qedf_debugfs_ops qedf_debugfs_ops;
-extern struct file_operations qedf_dbg_fops;
-
 /*
  * Driver module parameters.
  */
@@ -3155,8 +3153,8 @@ static int __qedf_probe(struct pci_dev *pdev, int mode)
 	}
 
 #ifdef CONFIG_DEBUG_FS
-	qedf_dbg_host_init(&(qedf->dbg_ctx), &qedf_debugfs_ops,
-			    &qedf_dbg_fops);
+	qedf_dbg_host_init(&(qedf->dbg_ctx), qedf_debugfs_ops,
+			    qedf_dbg_fops);
 #endif
 
 	/* Start LL2 */
-- 
2.9.0

[PATCH 5/6] scsi: qedi: fix building with LTO

[Arnd Bergmann]

When link-time optimizations are enabled, qedi fails to build because
of mismatched prototypes:

drivers/scsi/qedi/qedi_gbl.h:27:37: error: type of 'qedi_dbg_fops' does not match original declaration [-Werror=lto-type-mismatch]
 extern const struct file_operations qedi_dbg_fops;
                                     ^
drivers/scsi/qedi/qedi_debugfs.c:239:30: note: 'qedi_dbg_fops' was previously declared here
 const struct file_operations qedi_dbg_fops[] = {
                              ^
drivers/scsi/qedi/qedi_gbl.h:26:32: error: type of 'qedi_debugfs_ops' does not match original declaration [-Werror=lto-type-mismatch]
 extern struct qedi_debugfs_ops qedi_debugfs_ops;
                                ^
drivers/scsi/qedi/qedi_debugfs.c:102:25: note: 'qedi_debugfs_ops' was previously declared here
 struct qedi_debugfs_ops qedi_debugfs_ops[] = {

This changes the declaration to match the definition, and adapts the
users as necessary. Since both array can be constant here, I'm adding
the 'const' everywhere for consistency.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/scsi/qedi/qedi_dbg.h     | 2 +-
 drivers/scsi/qedi/qedi_debugfs.c | 4 ++--
 drivers/scsi/qedi/qedi_gbl.h     | 4 ++--
 drivers/scsi/qedi/qedi_main.c    | 4 ++--
 4 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/qedi/qedi_dbg.h b/drivers/scsi/qedi/qedi_dbg.h
index c55572badfb0..358f40567849 100644
--- a/drivers/scsi/qedi/qedi_dbg.h
+++ b/drivers/scsi/qedi/qedi_dbg.h
@@ -134,7 +134,7 @@ struct qedi_debugfs_ops {
 }
 
 void qedi_dbg_host_init(struct qedi_dbg_ctx *qedi,
-			struct qedi_debugfs_ops *dops,
+			const struct qedi_debugfs_ops *dops,
 			const struct file_operations *fops);
 void qedi_dbg_host_exit(struct qedi_dbg_ctx *qedi);
 void qedi_dbg_init(char *drv_name);
diff --git a/drivers/scsi/qedi/qedi_debugfs.c b/drivers/scsi/qedi/qedi_debugfs.c
index fd8a1eea3163..fd914ca4149a 100644
--- a/drivers/scsi/qedi/qedi_debugfs.c
+++ b/drivers/scsi/qedi/qedi_debugfs.c
@@ -19,7 +19,7 @@ static struct dentry *qedi_dbg_root;
 
 void
 qedi_dbg_host_init(struct qedi_dbg_ctx *qedi,
-		   struct qedi_debugfs_ops *dops,
+		   const struct qedi_debugfs_ops *dops,
 		   const struct file_operations *fops)
 {
 	char host_dirname[32];
@@ -99,7 +99,7 @@ static struct qedi_list_of_funcs qedi_dbg_do_not_recover_ops[] = {
 	{ NULL, NULL }
 };
 
-struct qedi_debugfs_ops qedi_debugfs_ops[] = {
+const struct qedi_debugfs_ops qedi_debugfs_ops[] = {
 	{ "gbl_ctx", NULL },
 	{ "do_not_recover", qedi_dbg_do_not_recover_ops},
 	{ "io_trace", NULL },
diff --git a/drivers/scsi/qedi/qedi_gbl.h b/drivers/scsi/qedi/qedi_gbl.h
index f5b5a31999aa..a2aa06ed1620 100644
--- a/drivers/scsi/qedi/qedi_gbl.h
+++ b/drivers/scsi/qedi/qedi_gbl.h
@@ -23,8 +23,8 @@ extern uint qedi_io_tracing;
 extern struct scsi_host_template qedi_host_template;
 extern struct iscsi_transport qedi_iscsi_transport;
 extern const struct qed_iscsi_ops *qedi_ops;
-extern struct qedi_debugfs_ops qedi_debugfs_ops;
-extern const struct file_operations qedi_dbg_fops;
+extern const struct qedi_debugfs_ops qedi_debugfs_ops[];
+extern const struct file_operations qedi_dbg_fops[];
 extern struct device_attribute *qedi_shost_attrs[];
 
 int qedi_alloc_sq(struct qedi_ctx *qedi, struct qedi_endpoint *ep);
diff --git a/drivers/scsi/qedi/qedi_main.c b/drivers/scsi/qedi/qedi_main.c
index 029e2e69b29f..e992f9d3ef00 100644
--- a/drivers/scsi/qedi/qedi_main.c
+++ b/drivers/scsi/qedi/qedi_main.c
@@ -2303,8 +2303,8 @@ static int __qedi_probe(struct pci_dev *pdev, int mode)
 	}
 
 #ifdef CONFIG_DEBUG_FS
-	qedi_dbg_host_init(&qedi->dbg_ctx, &qedi_debugfs_ops,
-			   &qedi_dbg_fops);
+	qedi_dbg_host_init(&qedi->dbg_ctx, qedi_debugfs_ops,
+			   qedi_dbg_fops);
 #endif
 	QEDI_INFO(&qedi->dbg_ctx, QEDI_LOG_INFO,
 		  "QLogic FastLinQ iSCSI Module qedi %s, FW %d.%d.%d.%d\n",
-- 
2.9.0

[PATCH 6/6] scsi: qedf: use correct strncpy() size

[Arnd Bergmann]

gcc-8 warns during link-time optimization that the strncpy() call
passes the size of the source buffer rather than the destination:

drivers/scsi/qedf/qedf_dbg.c: In function 'qedf_uevent_emit':
include/linux/string.h:253: error: 'strncpy' specified bound depends on the length of the source argument [-Werror=stringop-overflow=]

This changes it to strscpy() with the correct length, guaranteeing
a properly nul-terminated string of the right size.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/scsi/qedf/qedf_dbg.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/qedf/qedf_dbg.c b/drivers/scsi/qedf/qedf_dbg.c
index e023f5d0dc12..bd1cef25a900 100644
--- a/drivers/scsi/qedf/qedf_dbg.c
+++ b/drivers/scsi/qedf/qedf_dbg.c
@@ -160,7 +160,7 @@ qedf_uevent_emit(struct Scsi_Host *shost, u32 code, char *msg)
 	switch (code) {
 	case QEDF_UEVENT_CODE_GRCDUMP:
 		if (msg)
-			strncpy(event_string, msg, strlen(msg));
+			strscpy(event_string, msg, sizeof(event_string));
 		else
 			sprintf(event_string, "GRCDUMP=%u", shost->host_no);
 		break;
-- 
2.9.0

Re: [PATCH 6/6] scsi: qedf: use correct strncpy() size

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 1976 bytes --]

Hi Arnd,

I love your patch! Perhaps something to improve:

[auto build test WARNING on scsi/for-next]
[also build test WARNING on v4.15]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Arnd-Bergmann/scsi-fixes-for-building-with-LTO/20180205-083607
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi.git for-next
config: xtensa-allmodconfig (attached as .config)
compiler: xtensa-linux-gcc (GCC) 7.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=xtensa 

All warnings (new ones prefixed by >>):

   drivers/scsi//qedf/qedf_dbg.c: In function 'qedf_uevent_emit':
>> drivers/scsi//qedf/qedf_dbg.c:163:4: warning: ignoring return value of 'strscpy', declared with attribute warn_unused_result [-Wunused-result]
       strscpy(event_string, msg, sizeof(event_string));
       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

vim +/strscpy +163 drivers/scsi//qedf/qedf_dbg.c

   152	
   153	void
   154	qedf_uevent_emit(struct Scsi_Host *shost, u32 code, char *msg)
   155	{
   156		char event_string[40];
   157		char *envp[] = {event_string, NULL};
   158	
   159		memset(event_string, 0, sizeof(event_string));
   160		switch (code) {
   161		case QEDF_UEVENT_CODE_GRCDUMP:
   162			if (msg)
 > 163				strscpy(event_string, msg, sizeof(event_string));
   164			else
   165				sprintf(event_string, "GRCDUMP=%u", shost->host_no);
   166			break;
   167		default:
   168			/* do nothing */
   169			break;
   170		}
   171	
   172		kobject_uevent_env(&shost->shost_gendev.kobj, KOBJ_CHANGE, envp);
   173	}
   174	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

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Re: [PATCH 6/6] scsi: qedf: use correct strncpy() size

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 1976 bytes --]

Hi Arnd,

I love your patch! Perhaps something to improve:

[auto build test WARNING on scsi/for-next]
[also build test WARNING on v4.15]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Arnd-Bergmann/scsi-fixes-for-building-with-LTO/20180205-083607
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi.git for-next
config: xtensa-allmodconfig (attached as .config)
compiler: xtensa-linux-gcc (GCC) 7.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=xtensa 

All warnings (new ones prefixed by >>):

   drivers/scsi//qedf/qedf_dbg.c: In function 'qedf_uevent_emit':
>> drivers/scsi//qedf/qedf_dbg.c:163:4: warning: ignoring return value of 'strscpy', declared with attribute warn_unused_result [-Wunused-result]
       strscpy(event_string, msg, sizeof(event_string));
       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

vim +/strscpy +163 drivers/scsi//qedf/qedf_dbg.c

   152	
   153	void
   154	qedf_uevent_emit(struct Scsi_Host *shost, u32 code, char *msg)
   155	{
   156		char event_string[40];
   157		char *envp[] = {event_string, NULL};
   158	
   159		memset(event_string, 0, sizeof(event_string));
   160		switch (code) {
   161		case QEDF_UEVENT_CODE_GRCDUMP:
   162			if (msg)
 > 163				strscpy(event_string, msg, sizeof(event_string));
   164			else
   165				sprintf(event_string, "GRCDUMP=%u", shost->host_no);
   166			break;
   167		default:
   168			/* do nothing */
   169			break;
   170		}
   171	
   172		kobject_uevent_env(&shost->shost_gendev.kobj, KOBJ_CHANGE, envp);
   173	}
   174	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

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Re: [PATCH 5/6] scsi: qedi: fix building with LTO

[Rangankar, Manish]

On 02/02/18 6:42 PM, "Arnd Bergmann" <arnd@arndb.de> wrote:

>When link-time optimizations are enabled, qedi fails to build because
>of mismatched prototypes:
>
>drivers/scsi/qedi/qedi_gbl.h:27:37: error: type of 'qedi_dbg_fops' does
>not match original declaration [-Werror=lto-type-mismatch]
> extern const struct file_operations qedi_dbg_fops;
>                                     ^
>drivers/scsi/qedi/qedi_debugfs.c:239:30: note: 'qedi_dbg_fops' was
>previously declared here
> const struct file_operations qedi_dbg_fops[] = {
>                              ^
>drivers/scsi/qedi/qedi_gbl.h:26:32: error: type of 'qedi_debugfs_ops'
>does not match original declaration [-Werror=lto-type-mismatch]
> extern struct qedi_debugfs_ops qedi_debugfs_ops;
>                                ^
>drivers/scsi/qedi/qedi_debugfs.c:102:25: note: 'qedi_debugfs_ops' was
>previously declared here
> struct qedi_debugfs_ops qedi_debugfs_ops[] = {
>
>This changes the declaration to match the definition, and adapts the
>users as necessary. Since both array can be constant here, I'm adding
>the 'const' everywhere for consistency.
>
>Signed-off-by: Arnd Bergmann <arnd@arndb.de>
>---
> drivers/scsi/qedi/qedi_dbg.h     | 2 +-
> drivers/scsi/qedi/qedi_debugfs.c | 4 ++--
> drivers/scsi/qedi/qedi_gbl.h     | 4 ++--
> drivers/scsi/qedi/qedi_main.c    | 4 ++--
> 4 files changed, 7 insertions(+), 7 deletions(-)
>
>diff --git a/drivers/scsi/qedi/qedi_dbg.h b/drivers/scsi/qedi/qedi_dbg.h
>index c55572badfb0..358f40567849 100644
>--- a/drivers/scsi/qedi/qedi_dbg.h
>+++ b/drivers/scsi/qedi/qedi_dbg.h
>@@ -134,7 +134,7 @@ struct qedi_debugfs_ops {
> }
> 
> void qedi_dbg_host_init(struct qedi_dbg_ctx *qedi,
>-			struct qedi_debugfs_ops *dops,
>+			const struct qedi_debugfs_ops *dops,
> 			const struct file_operations *fops);
> void qedi_dbg_host_exit(struct qedi_dbg_ctx *qedi);
> void qedi_dbg_init(char *drv_name);
>diff --git a/drivers/scsi/qedi/qedi_debugfs.c
>b/drivers/scsi/qedi/qedi_debugfs.c
>index fd8a1eea3163..fd914ca4149a 100644
>--- a/drivers/scsi/qedi/qedi_debugfs.c
>+++ b/drivers/scsi/qedi/qedi_debugfs.c
>@@ -19,7 +19,7 @@ static struct dentry *qedi_dbg_root;
> 
> void
> qedi_dbg_host_init(struct qedi_dbg_ctx *qedi,
>-		   struct qedi_debugfs_ops *dops,
>+		   const struct qedi_debugfs_ops *dops,
> 		   const struct file_operations *fops)
> {
> 	char host_dirname[32];
>@@ -99,7 +99,7 @@ static struct qedi_list_of_funcs
>qedi_dbg_do_not_recover_ops[] = {
> 	{ NULL, NULL }
> };
> 
>-struct qedi_debugfs_ops qedi_debugfs_ops[] = {
>+const struct qedi_debugfs_ops qedi_debugfs_ops[] = {
> 	{ "gbl_ctx", NULL },
> 	{ "do_not_recover", qedi_dbg_do_not_recover_ops},
> 	{ "io_trace", NULL },
>diff --git a/drivers/scsi/qedi/qedi_gbl.h b/drivers/scsi/qedi/qedi_gbl.h
>index f5b5a31999aa..a2aa06ed1620 100644
>--- a/drivers/scsi/qedi/qedi_gbl.h
>+++ b/drivers/scsi/qedi/qedi_gbl.h
>@@ -23,8 +23,8 @@ extern uint qedi_io_tracing;
> extern struct scsi_host_template qedi_host_template;
> extern struct iscsi_transport qedi_iscsi_transport;
> extern const struct qed_iscsi_ops *qedi_ops;
>-extern struct qedi_debugfs_ops qedi_debugfs_ops;
>-extern const struct file_operations qedi_dbg_fops;
>+extern const struct qedi_debugfs_ops qedi_debugfs_ops[];
>+extern const struct file_operations qedi_dbg_fops[];
> extern struct device_attribute *qedi_shost_attrs[];
> 
> int qedi_alloc_sq(struct qedi_ctx *qedi, struct qedi_endpoint *ep);
>diff --git a/drivers/scsi/qedi/qedi_main.c b/drivers/scsi/qedi/qedi_main.c
>index 029e2e69b29f..e992f9d3ef00 100644
>--- a/drivers/scsi/qedi/qedi_main.c
>+++ b/drivers/scsi/qedi/qedi_main.c
>@@ -2303,8 +2303,8 @@ static int __qedi_probe(struct pci_dev *pdev, int
>mode)
> 	}
> 
> #ifdef CONFIG_DEBUG_FS
>-	qedi_dbg_host_init(&qedi->dbg_ctx, &qedi_debugfs_ops,
>-			   &qedi_dbg_fops);
>+	qedi_dbg_host_init(&qedi->dbg_ctx, qedi_debugfs_ops,
>+			   qedi_dbg_fops);
> #endif
> 	QEDI_INFO(&qedi->dbg_ctx, QEDI_LOG_INFO,
> 		  "QLogic FastLinQ iSCSI Module qedi %s, FW %d.%d.%d.%d\n",
>-- 
>2.9.0

Thanks

Acked-by: Manish Rangankar <Manish.Rangankar@cavium.com>


>

Re: [PATCH 5/6] scsi: qedi: fix building with LTO

[Martin K. Petersen]

Arnd,

> When link-time optimizations are enabled, qedi fails to build because
> of mismatched prototypes:

Applied to 4.17/scsi-queue. Thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

Re: [PATCH 4/6] scsi: qedf: fix LTO-enabled build

[Chad Dupuis]

On Fri, 2 Feb 2018, 8:12am, Arnd Bergmann wrote:

> The prototype for qedf_dbg_fops/qedf_debugfs_ops doesn't match the definition,
> which causes the final link to fail with link-time optimizations:
> 
> drivers/scsi/qedf/qedf_main.c:34: error: type of 'qedf_dbg_fops' does not match original declaration [-Werror=lto-type-mismatch]
>  extern struct file_operations qedf_dbg_fops;
> 
> drivers/scsi/qedf/qedf_debugfs.c:443: note: 'qedf_dbg_fops' was previously declared here
>  const struct file_operations qedf_dbg_fops[] = {
> 
> drivers/scsi/qedf/qedf_main.c:33: error: type of 'qedf_debugfs_ops' does not match original declaration [-Werror=lto-type-mismatch]
>  extern struct qedf_debugfs_ops qedf_debugfs_ops;
> 
> drivers/scsi/qedf/qedf_debugfs.c:102: note: 'qedf_debugfs_ops' was previously declared here
>  struct qedf_debugfs_ops qedf_debugfs_ops[] = {
> 
> This corrects the prototype and moves it into a shared header file where it
> belongs. The file operations can also be marked 'const' like the
> qedf_debugfs_ops.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  drivers/scsi/qedf/qedf_dbg.h     | 17 ++++++++++-------
>  drivers/scsi/qedf/qedf_debugfs.c |  6 +++---
>  drivers/scsi/qedf/qedf_main.c    |  8 +++-----
>  3 files changed, 16 insertions(+), 15 deletions(-)
> 

Thanks.

Acked-by: Chad Dupuis <chad.dupuis@cavium.com>

Re: [PATCH 6/6] scsi: qedf: use correct strncpy() size

[Chad Dupuis]

On Fri, 2 Feb 2018, 8:12am, Arnd Bergmann wrote:

> gcc-8 warns during link-time optimization that the strncpy() call
> passes the size of the source buffer rather than the destination:
> 
> drivers/scsi/qedf/qedf_dbg.c: In function 'qedf_uevent_emit':
> include/linux/string.h:253: error: 'strncpy' specified bound depends on the length of the source argument [-Werror=stringop-overflow=]
> 
> This changes it to strscpy() with the correct length, guaranteeing
> a properly nul-terminated string of the right size.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  drivers/scsi/qedf/qedf_dbg.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 

Reasonable security precaution.

Acked-by: Chad Dupuis <chad.dupuis@cavium.com>

Re: [PATCH 4/6] scsi: qedf: fix LTO-enabled build

[Martin K. Petersen]

Arnd,

> The prototype for qedf_dbg_fops/qedf_debugfs_ops doesn't match the
> definition, which causes the final link to fail with link-time
> optimizations:

Applied to 4.17/scsi-queue. Thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

Re: [PATCH 6/6] scsi: qedf: use correct strncpy() size

[Martin K. Petersen]

Arnd,

> gcc-8 warns during link-time optimization that the strncpy() call
> passes the size of the source buffer rather than the destination:

Applied to 4.17/scsi-queue. Thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

Re: [PATCH 6/6] scsi: qedf: use correct strncpy() size

[Martin K. Petersen]

Arnd,

> gcc-8 warns during link-time optimization that the strncpy() call
> passes the size of the source buffer rather than the destination:

Applied to 4.17/scsi-queue. Thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

Re: [PATCH 2/6] scsi: NCR53c406a: avoid section mismatch with LTO

[Martin K. Petersen]

Arnd,

> Building with link time optimizations produces a false-postive section
> mismatch warning:

Applied to 4.17/scsi-queue, thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

Re: [PATCH 3/6] scsi: sym53c416: avoid section mismatch with LTO

[Martin K. Petersen]

Arnd,

> Building with link time optimizations produces a false-postive section
> mismatch warning:

Applied to 4.17/scsi-queue, thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering