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vmci_host: print unexpanded names of ioctl requests in debug messages
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__stringify macro function expands its arguments, but in this messages
we expect to see ioctl request name instead of it's _IOC macro
expansion.

$ cat stringify.c

#include <stdio.h>
#include <asm/ioctl.h>

#define __stringify_1(x)	#x
#define __stringify(x)		__stringify_1(x)

#define VMCI_DO_IOCTL(ioctl_name) \
    char *name = __stringify(IOCTL_VMCI_ ## ioctl_name);

int main() {
        VMCI_DO_IOCTL(INIT_CONTEXT)
        printf("%s\n", name);
}
$ cc stringify.c
$ ./a.out
(((0U) << (((0+8)+8)+14)) | (((7)) << (0+8)) | (((0xa0)) << 0) | ((0) << ((0+8)+8)))

Signed-off-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Link: https://lore.kernel.org/r/20210302153346.300416-1-glebfm@altlinux.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Gleb Fotengauer-Malinovskiy authored and Greg Kroah-Hartman committed Mar 24, 2021
1 parent ac41ae0 commit 7b7d226
Showing 1 changed file with 1 addition and 1 deletion.
2 changes: 1 addition & 1 deletion drivers/misc/vmw_vmci/vmci_host.c
Original file line number Diff line number Diff line change
@@ -908,7 +908,7 @@ static long vmci_host_unlocked_ioctl(struct file *filp,
unsigned int iocmd, unsigned long ioarg)
{
#define VMCI_DO_IOCTL(ioctl_name, ioctl_fn) do { \
char *name = __stringify(IOCTL_VMCI_ ## ioctl_name); \
char *name = "IOCTL_VMCI_" # ioctl_name; \
return vmci_host_do_ ## ioctl_fn( \
vmci_host_dev, name, uptr); \
} while (0)

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