diff -ur lin_tape-3.0.18/Makefile lin_tape-3.0.18-ifdefs/Makefile
--- lin_tape-3.0.18/Makefile	2017-05-09 21:11:32.977092391 +0200
+++ lin_tape-3.0.18-ifdefs/Makefile	2017-05-09 21:05:59.610307494 +0200
@@ -20,26 +20,6 @@
 lin_tape-objs := join.o lin_tape_scsi_config.o lin_tape_scsi_tape.o lin_tape_scsi_trace.o \
              lin_tape_ioctl_tape.o lin_tape_ioctl_changer.o lin_tape_extra_ioctl.o
 
-RHELRELEASE := $(shell [ -f "/etc/redhat-release" ] && echo 1 || echo 0)
-ifeq ($(RHELRELEASE), 1)
-KERNELDIR ?= /lib/modules/$(shell uname -r)/build
-KERNELVER = $(shell uname -r 2>/dev/null|sed "s/[\.-]/_/g"|sed "s/\([0-9]*_[0-9]*_[0-9]*_[0-9]*\).*/\1/")
-EXTRA_CFLAGS += -DKERNELVERSION_${KERNELVER}
-else
-UBUNTURELEASE := $(shell [ -f "/etc/os-release" ] && grep -qi Ubuntu /etc/os-release && echo 1 || echo 0)
-ifeq ($(UBUNTURELEASE), 1)
-EXTRA_CFLAGS += -DUBUNTUVERSION
-else
-EXTRA_CFLAGS += -DSLESVERSION
-KERNELDIR ?= /lib/modules/$(shell uname -r)/build
-KERNELVER = $(shell uname -r 2>/dev/null|sed "s/[\.-]/_/g"|sed "s/\([0-9]*_[0-9]*_[0-9]*_[0-9]*\).*/\1/")
-EXTRA_CFLAGS += -DSLESKERNEL_${KERNELVER}
-SLESSP2 := $(shell grep -qi SP2 /etc/*release && echo 1 || echo 0)
-ifeq ($(SLESSP2), 1)
-EXTRA_CFLAGS += -DSLESSP2
-endif
-endif
-endif
 
 ifeq ($(SFMP), 1)
 EXTRA_CFLAGS += -DSFMPENABLED
diff -ur lin_tape-3.0.18/pfo.h lin_tape-3.0.18-ifdefs/pfo.h
--- lin_tape-3.0.18/pfo.h	2017-02-23 19:14:41.000000000 +0100
+++ lin_tape-3.0.18-ifdefs/pfo.h	2017-05-09 21:06:34.117699008 +0200
@@ -26,133 +26,6 @@
  * will build for various releases of Linux.  This is how
  * we track different versions using ifdef in the source.
  */
-#ifdef KERNELVERSION_2_6_32_220
-#define BEFORE_RH_63 1
-#define BEFORE_RH_64 1
-#define BEFORE_RH_65 1
-#define BEFORE_RH_66 1
-#define BEFORE_RH_67 1
-#define BEFORE_RH_70 1
-#define BEFORE_RH_71 1
-#define BEFORE_RH_72 1
-#endif
-#ifdef KERNELVERSION_2_6_32_279
-#define AFTER_RH_62 1
-#define BEFORE_RH_64 1
-#define BEFORE_RH_65 1
-#define BEFORE_RH_66 1
-#define BEFORE_RH_67 1
-#define BEFORE_RH_70 1
-#define BEFORE_RH_71 1
-#define BEFORE_RH_72 1
-#endif
-#ifdef KERNELVERSION_2_6_32_358
-#define AFTER_RH_62 1
-#define AFTER_RH_63 1
-#define BEFORE_RH_65 1
-#define BEFORE_RH_66 1
-#define BEFORE_RH_67 1
-#define BEFORE_RH_70 1
-#define BEFORE_RH_72 1
-#endif
-#ifdef KERNELVERSION_2_6_32_431
-#define AFTER_RH_62 1
-#define AFTER_RH_63 1
-#define AFTER_RH_64 1
-#define BEFORE_RH_66 1
-#define BEFORE_RH_67 1
-#define BEFORE_RH_70 1
-#define BEFORE_RH_71 1
-#define BEFORE_RH_72 1
-#endif
-#ifdef KERNELVERSION_2_6_32_504
-#define AFTER_RH_62 1
-#define AFTER_RH_63 1
-#define AFTER_RH_64 1
-#define AFTER_RH_65 1
-#define BEFORE_RH_67 1
-#define BEFORE_RH_70 1
-#define BEFORE_RH_71 1
-#define BEFORE_RH_72 1
-#endif
-#ifdef KERNELVERSION_2_6_32_573
-#define AFTER_RH_62 1
-#define AFTER_RH_63 1
-#define AFTER_RH_64 1
-#define AFTER_RH_65 1
-#define AFTER_RH_66 1
-#define BEFORE_RH_70 1
-#define BEFORE_RH_71 1
-#define BEFORE_RH_72 1
-#endif
-#ifdef KERNELVERSION_2_6_32_642
-#define AFTER_RH_62 1
-#define AFTER_RH_63 1
-#define AFTER_RH_64 1
-#define AFTER_RH_65 1
-#define AFTER_RH_66 1
-#define AFTER_RH_67 1
-#define BEFORE_RH_70 1
-#define BEFORE_RH_71 1
-#define BEFORE_RH_72 1
-#endif
-#ifdef KERNELVERSION_2_6_32_696
-#define AFTER_RH_62 1
-#define AFTER_RH_63 1
-#define AFTER_RH_64 1
-#define AFTER_RH_65 1
-#define AFTER_RH_66 1
-#define AFTER_RH_67 1
-#define AFTER_RH_68 1
-#define BEFORE_RH_70 1
-#define BEFORE_RH_71 1
-#define BEFORE_RH_72 1
-#endif
-#ifdef KERNELVERSION_3_10_0_123
-#define AFTER_RH_62 1
-#define AFTER_RH_63 1
-#define AFTER_RH_64 1
-#define AFTER_RH_65 1
-#define AFTER_RH_66 1
-#define AFTER_RH_67 1
-#define AFTER_RH_6x 1
-#define BEFORE_RH_71 1
-#endif
-#ifdef KERNELVERSION_3_10_0_229
-#define AFTER_RH_62 1
-#define AFTER_RH_63 1
-#define AFTER_RH_64 1
-#define AFTER_RH_65 1
-#define AFTER_RH_66 1
-#define AFTER_RH_67 1
-#define AFTER_RH_6x 1
-#define AFTER_RH_70 1
-#define BEFORE_RH_72 1
-#endif
-#ifdef KERNELVERSION_3_10_0_327
-#define AFTER_RH_62 1
-#define AFTER_RH_63 1
-#define AFTER_RH_64 1
-#define AFTER_RH_65 1
-#define AFTER_RH_66 1
-#define AFTER_RH_67 1
-#define AFTER_RH_6x 1
-#define AFTER_RH_70 1
-#define AFTER_RH_71 1
-#endif
-#ifdef KERNELVERSION_3_10_0_514
-#define AFTER_RH_62 1
-#define AFTER_RH_63 1
-#define AFTER_RH_64 1
-#define AFTER_RH_65 1
-#define AFTER_RH_66 1
-#define AFTER_RH_67 1
-#define AFTER_RH_6x 1
-#define AFTER_RH_70 1
-#define AFTER_RH_71 1
-#define AFTER_RH_72 1
-#endif
-#ifdef KERNELVERSION_3_10_0_693
 #define AFTER_RH_62 1
 #define AFTER_RH_63 1
 #define AFTER_RH_64 1
@@ -126,7 +35,6 @@
 #define AFTER_RH_71 1
 #define AFTER_RH_72 1
 #define AFTER_RH_73 1
-#endif
 
 /* Misc defines needed so source is same for all versions of Linux */
 #ifndef SDEV_TRANSPORT_OFFLINE
--- lin_tape-3.0.52/lin_tape_scsi_config.h~	2020-04-04 21:53:09.000000000 +0200
+++ lin_tape-3.0.52/lin_tape_scsi_config.h	2020-04-04 21:56:46.600032193 +0200
@@ -64,9 +64,6 @@
     ("IBM Tape Drives and Libraries");
 MODULE_LICENSE("GPL");
 MODULE_VERSION("3.0.56");
-#if defined(SLESVERSION)
-MODULE_INFO(supported, "external");
-#endif // defined
 /* driver parameters */
 int support_dio = 1;
 module_param(support_dio, int, 0);
--- lin_tape-3.0.52/sgmp.c~	2020-03-05 19:43:09.000000000 +0100
+++ lin_tape-3.0.52/sgmp.c	2020-04-04 21:57:56.793366544 +0200
@@ -34,7 +34,7 @@
  */
 
 #include <linux/version.h>
-#if !defined(SLESVERSION) && LINUX_VERSION_CODE >= KERNEL_VERSION(4,14,0)
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,14,0)
 /*
  *  History:
  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
@@ -3012,7 +3012,7 @@
 	return 0;
 }
 #endif				/* CONFIG_SCSI_PROC_FS */
-#elif !defined(SLESVERSION) && LINUX_VERSION_CODE >= KERNEL_VERSION(3,10,0)
+#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3,10,0)
 static int sg_version_num = 30536;	/* 2 digits for each component */
 #define SG_VERSION_STR "3.5.36"
 
@@ -6026,7 +6026,7 @@
 }
 
 #endif				/* CONFIG_SCSI_PROC_FS */
-#elif !defined(SLESVERSION) && LINUX_VERSION_CODE == KERNEL_VERSION(2,6,32)
+#elif LINUX_VERSION_CODE == KERNEL_VERSION(2,6,32)
 static int sg_version_num = 30534;	/* 2 digits for each component */
 #define SG_VERSION_STR "3.5.34"
 
--- lin_tape-3.0.52/stmp.c~	2020-03-05 19:43:09.000000000 +0100
+++ lin_tape-3.0.52/stmp.c	2020-04-04 21:58:35.473367112 +0200
@@ -42,7 +42,7 @@
 
  */
 #include <linux/version.h>
-#if !defined(SLESVERSION) && LINUX_VERSION_CODE >= KERNEL_VERSION(4,14,0)
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,14,0)
 /*
    SCSI Tape Driver for Linux version 1.1 and newer. See the accompanying
    file Documentation/scsi/st.txt for more information.
@@ -5108,7 +5108,7 @@
 
 	return 0;
 }
-#elif !defined(SLESVERSION) && LINUX_VERSION_CODE >= KERNEL_VERSION(3,10,0)
+#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3,10,0)
 #include <linux/module.h>
 #include <linux/fs.h>
 #include <linux/kernel.h>
@@ -10137,7 +10137,7 @@
 
 	return 0;
 }
-#elif !defined(SLESVERSION) && LINUX_VERSION_CODE == KERNEL_VERSION(2,6,32)
+#elif LINUX_VERSION_CODE == KERNEL_VERSION(2,6,32)
 #include <linux/module.h>
 #include <linux/fs.h>
 #include <linux/kernel.h>
--- lin_tape-3.0.52/upper.c~	2020-04-04 21:55:46.000000000 +0200
+++ lin_tape-3.0.52/upper.c	2020-04-04 21:59:12.536700966 +0200
@@ -273,7 +273,7 @@
 	if (copy_from_user(pfo_cmd->scsi_cmd, hdr->cmdp, hdr->cmd_len))
 		return -EFAULT;
 
-#if LINUX_VERSION_CODE > KERNEL_VERSION(3,12,0) && (defined(SLESVERSION) || defined(UBUNTUVERSION))
+#if LINUX_VERSION_CODE > KERNEL_VERSION(3,12,0)
 	if (blk_verify_command(pfo_cmd->scsi_cmd, mode & FMODE_WRITE))
 #else
 	/* RHEL 6.4 and beyond */
@@ -525,14 +525,12 @@
 		/* SG_IO howto says that the shorter of the two wins */
 		iov_data_len = iov_length((struct iovec *)iov,
 					hdr->iovec_count);
-#if !defined (UBUNTUVERSION)
 		if (hdr->dxfer_len < iov_data_len) {
 			hdr->iovec_count = iov_shorten((struct iovec *)iov,
 							hdr->iovec_count,
 							hdr->dxfer_len);
 			iov_data_len = hdr->dxfer_len;
 		}
-#endif
 		pfo_cmd.buffer = iov;
 		pfo_cmd.bufflen = iov_data_len;
 		pfo_cmd.iov_count = hdr->iovec_count;
@@ -622,7 +620,7 @@
 	if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
 		goto error;
 
-#if LINUX_VERSION_CODE > KERNEL_VERSION(3,12,0) && (defined(SLESVERSION) || defined(UBUNTUVERSION))
+#if LINUX_VERSION_CODE > KERNEL_VERSION(3,12,0)
 	err = blk_verify_command(scsi_cmd, mode & FMODE_WRITE);
 #else
 	/* RHEL 6.4 and beyond */
--- lin_tape-3.0.52/intercept.c~	2020-03-05 19:43:09.000000000 +0100
+++ lin_tape-3.0.52/intercept.c	2020-04-04 21:59:43.190034776 +0200
@@ -2492,9 +2492,6 @@
 MODULE_LICENSE("GPL");
 MODULE_VERSION(PFO_VERSION_STR);
 MODULE_INFO(date, PFO_DATE_STR);
-#if defined(SLESVERSION)
-MODULE_INFO(supported, "external");
-#endif
 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,32)
 module_param(netbackup, int, 0444);
 MODULE_PARM_DESC(netbackup, "!=0 to use with NetBackup application");