Merge tag 'mm-nonmm-stable-2023-02-20-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:
 "There is no particular theme here - mainly quick hits all over the
  tree.

  Most notable is a set of zlib changes from Mikhail Zaslonko which
  enhances and fixes zlib's use of S390 hardware support: 'lib/zlib: Set
  of s390 DFLTCC related patches for kernel zlib'"

* tag 'mm-nonmm-stable-2023-02-20-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (55 commits)
  Update CREDITS file entry for Jesper Juhl
  sparc: allow PM configs for sparc32 COMPILE_TEST
  hung_task: print message when hung_task_warnings gets down to zero.
  arch/Kconfig: fix indentation
  scripts/tags.sh: fix the Kconfig tags generation when using latest ctags
  nilfs2: prevent WARNING in nilfs_dat_commit_end()
  lib/zlib: remove redundation assignement of avail_in dfltcc_gdht()
  lib/Kconfig.debug: do not enable DEBUG_PREEMPT by default
  lib/zlib: DFLTCC always switch to software inflate for Z_PACKET_FLUSH option
  lib/zlib: DFLTCC support inflate with small window
  lib/zlib: Split deflate and inflate states for DFLTCC
  lib/zlib: DFLTCC not writing header bits when avail_out == 0
  lib/zlib: fix DFLTCC ignoring flush modes when avail_in == 0
  lib/zlib: fix DFLTCC not flushing EOBS when creating raw streams
  lib/zlib: implement switching between DFLTCC and software
  lib/zlib: adjust offset calculation for dfltcc_state
  nilfs2: replace WARN_ONs for invalid DAT metadata block requests
  scripts/spelling.txt: add "exsits" pattern and fix typo instances
  fs: gracefully handle ->get_block not mapping bh in __mpage_writepage
  cramfs: Kconfig: fix spelling & punctuation
  ...

17 files changed, 1130 insertions, 138 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 2e91421e096e..c8b379e2e9ad 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1185,13 +1185,16 @@ config DEBUG_TIMEKEEPING
 config DEBUG_PREEMPT
 	bool "Debug preemptible kernel"
 	depends on DEBUG_KERNEL && PREEMPTION && TRACE_IRQFLAGS_SUPPORT
-	default y
 	help
 	  If you say Y here then the kernel will use a debug variant of the
 	  commonly used smp_processor_id() function and will print warnings
 	  if kernel code uses it in a preemption-unsafe way. Also, the kernel
 	  will detect preemption count underflows.
 
+	  This option has potential to introduce high runtime overhead,
+	  depending on workload as it triggers debugging routines for each
+	  this_cpu operation. It should only be used for debugging purposes.
+
 menu "Lock Debugging (spinlocks, mutexes, etc...)"
 
 config LOCK_DEBUGGING_SUPPORT
@@ -2029,6 +2032,41 @@ menuconfig RUNTIME_TESTING_MENU
 
 if RUNTIME_TESTING_MENU
 
+config TEST_DHRY
+	tristate "Dhrystone benchmark test"
+	help
+	  Enable this to include the Dhrystone 2.1 benchmark.  This test
+	  calculates the number of Dhrystones per second, and the number of
+	  DMIPS (Dhrystone MIPS) obtained when the Dhrystone score is divided
+	  by 1757 (the number of Dhrystones per second obtained on the VAX
+	  11/780, nominally a 1 MIPS machine).
+
+	  To run the benchmark, it needs to be enabled explicitly, either from
+	  the kernel command line (when built-in), or from userspace (when
+	  built-in or modular.
+
+	  Run once during kernel boot:
+
+	      test_dhry.run
+
+	  Set number of iterations from kernel command line:
+
+	      test_dhry.iterations=<n>
+
+	  Set number of iterations from userspace:
+
+	      echo <n> > /sys/module/test_dhry/parameters/iterations
+
+	  Trigger manual run from userspace:
+
+	      echo y > /sys/module/test_dhry/parameters/run
+
+	  If the number of iterations is <= 0, the test will devise a suitable
+	  number of iterations (test runs for at least 2s) automatically.
+	  This process takes ca. 4s.
+
+	  If unsure, say N.
+
 config LKDTM
 	tristate "Linux Kernel Dump Test Tool Module"
 	depends on DEBUG_FS
diff --git a/lib/Makefile b/lib/Makefile
index a269af847e2e..469be6240523 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -57,6 +57,8 @@ obj-$(CONFIG_TEST_HEXDUMP) += test_hexdump.o
 obj-y += kstrtox.o
 obj-$(CONFIG_FIND_BIT_BENCHMARK) += find_bit_benchmark.o
 obj-$(CONFIG_TEST_BPF) += test_bpf.o
+test_dhry-objs := dhry_1.o dhry_2.o dhry_run.o
+obj-$(CONFIG_TEST_DHRY) += test_dhry.o
 obj-$(CONFIG_TEST_FIRMWARE) += test_firmware.o
 obj-$(CONFIG_TEST_BITOPS) += test_bitops.o
 CFLAGS_test_bitops.o += -Werror
diff --git a/lib/dhry.h b/lib/dhry.h
new file mode 100644
index 000000000000..e1a4db8e252c
--- /dev/null
+++ b/lib/dhry.h
@@ -0,0 +1,358 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+/*
+ ****************************************************************************
+ *
+ *                   "DHRYSTONE" Benchmark Program
+ *                   -----------------------------
+ *
+ *  Version:    C, Version 2.1
+ *
+ *  File:       dhry.h (part 1 of 3)
+ *
+ *  Date:       May 25, 1988
+ *
+ *  Author:     Reinhold P. Weicker
+ *                      Siemens AG, AUT E 51
+ *                      Postfach 3220
+ *                      8520 Erlangen
+ *                      Germany (West)
+ *                              Phone:  [+49]-9131-7-20330
+ *                                      (8-17 Central European Time)
+ *                              Usenet: ..!mcsun!unido!estevax!weicker
+ *
+ *              Original Version (in Ada) published in
+ *              "Communications of the ACM" vol. 27., no. 10 (Oct. 1984),
+ *              pp. 1013 - 1030, together with the statistics
+ *              on which the distribution of statements etc. is based.
+ *
+ *              In this C version, the following C library functions are used:
+ *              - strcpy, strcmp (inside the measurement loop)
+ *              - printf, scanf (outside the measurement loop)
+ *              In addition, Berkeley UNIX system calls "times ()" or "time ()"
+ *              are used for execution time measurement. For measurements
+ *              on other systems, these calls have to be changed.
+ *
+ *  Collection of Results:
+ *              Reinhold Weicker (address see above) and
+ *
+ *              Rick Richardson
+ *              PC Research. Inc.
+ *              94 Apple Orchard Drive
+ *              Tinton Falls, NJ 07724
+ *                      Phone:  (201) 389-8963 (9-17 EST)
+ *                      Usenet: ...!uunet!pcrat!rick
+ *
+ *      Please send results to Rick Richardson and/or Reinhold Weicker.
+ *      Complete information should be given on hardware and software used.
+ *      Hardware information includes: Machine type, CPU, type and size
+ *      of caches; for microprocessors: clock frequency, memory speed
+ *      (number of wait states).
+ *      Software information includes: Compiler (and runtime library)
+ *      manufacturer and version, compilation switches, OS version.
+ *      The Operating System version may give an indication about the
+ *      compiler; Dhrystone itself performs no OS calls in the measurement loop.
+ *
+ *      The complete output generated by the program should be mailed
+ *      such that at least some checks for correctness can be made.
+ *
+ ***************************************************************************
+ *
+ *  History:    This version C/2.1 has been made for two reasons:
+ *
+ *              1) There is an obvious need for a common C version of
+ *              Dhrystone, since C is at present the most popular system
+ *              programming language for the class of processors
+ *              (microcomputers, minicomputers) where Dhrystone is used most.
+ *              There should be, as far as possible, only one C version of
+ *              Dhrystone such that results can be compared without
+ *              restrictions. In the past, the C versions distributed
+ *              by Rick Richardson (Version 1.1) and by Reinhold Weicker
+ *              had small (though not significant) differences.
+ *
+ *              2) As far as it is possible without changes to the Dhrystone
+ *              statistics, optimizing compilers should be prevented from
+ *              removing significant statements.
+ *
+ *              This C version has been developed in cooperation with
+ *              Rick Richardson (Tinton Falls, NJ), it incorporates many
+ *              ideas from the "Version 1.1" distributed previously by
+ *              him over the UNIX network Usenet.
+ *              I also thank Chaim Benedelac (National Semiconductor),
+ *              David Ditzel (SUN), Earl Killian and John Mashey (MIPS),
+ *              Alan Smith and Rafael Saavedra-Barrera (UC at Berkeley)
+ *              for their help with comments on earlier versions of the
+ *              benchmark.
+ *
+ *  Changes:    In the initialization part, this version follows mostly
+ *              Rick Richardson's version distributed via Usenet, not the
+ *              version distributed earlier via floppy disk by Reinhold Weicker.
+ *              As a concession to older compilers, names have been made
+ *              unique within the first 8 characters.
+ *              Inside the measurement loop, this version follows the
+ *              version previously distributed by Reinhold Weicker.
+ *
+ *              At several places in the benchmark, code has been added,
+ *              but within the measurement loop only in branches that
+ *              are not executed. The intention is that optimizing compilers
+ *              should be prevented from moving code out of the measurement
+ *              loop, or from removing code altogether. Since the statements
+ *              that are executed within the measurement loop have NOT been
+ *              changed, the numbers defining the "Dhrystone distribution"
+ *              (distribution of statements, operand types and locality)
+ *              still hold. Except for sophisticated optimizing compilers,
+ *              execution times for this version should be the same as
+ *              for previous versions.
+ *
+ *              Since it has proven difficult to subtract the time for the
+ *              measurement loop overhead in a correct way, the loop check
+ *              has been made a part of the benchmark. This does have
+ *              an impact - though a very minor one - on the distribution
+ *              statistics which have been updated for this version.
+ *
+ *              All changes within the measurement loop are described
+ *              and discussed in the companion paper "Rationale for
+ *              Dhrystone version 2".
+ *
+ *              Because of the self-imposed limitation that the order and
+ *              distribution of the executed statements should not be
+ *              changed, there are still cases where optimizing compilers
+ *              may not generate code for some statements. To a certain
+ *              degree, this is unavoidable for small synthetic benchmarks.
+ *              Users of the benchmark are advised to check code listings
+ *              whether code is generated for all statements of Dhrystone.
+ *
+ *              Version 2.1 is identical to version 2.0 distributed via
+ *              the UNIX network Usenet in March 1988 except that it corrects
+ *              some minor deficiencies that were found by users of version 2.0.
+ *              The only change within the measurement loop is that a
+ *              non-executed "else" part was added to the "if" statement in
+ *              Func_3, and a non-executed "else" part removed from Proc_3.
+ *
+ ***************************************************************************
+ *
+ *  Compilation model and measurement (IMPORTANT):
+ *
+ *  This C version of Dhrystone consists of three files:
+ *  - dhry.h (this file, containing global definitions and comments)
+ *  - dhry_1.c (containing the code corresponding to Ada package Pack_1)
+ *  - dhry_2.c (containing the code corresponding to Ada package Pack_2)
+ *
+ *  The following "ground rules" apply for measurements:
+ *  - Separate compilation
+ *  - No procedure merging
+ *  - Otherwise, compiler optimizations are allowed but should be indicated
+ *  - Default results are those without register declarations
+ *  See the companion paper "Rationale for Dhrystone Version 2" for a more
+ *  detailed discussion of these ground rules.
+ *
+ *  For 16-Bit processors (e.g. 80186, 80286), times for all compilation
+ *  models ("small", "medium", "large" etc.) should be given if possible,
+ *  together with a definition of these models for the compiler system used.
+ *
+ **************************************************************************
+ *
+ *  Dhrystone (C version) statistics:
+ *
+ *  [Comment from the first distribution, updated for version 2.
+ *   Note that because of language differences, the numbers are slightly
+ *   different from the Ada version.]
+ *
+ *  The following program contains statements of a high level programming
+ *  language (here: C) in a distribution considered representative:
+ *
+ *    assignments                  52 (51.0 %)
+ *    control statements           33 (32.4 %)
+ *    procedure, function calls    17 (16.7 %)
+ *
+ *  103 statements are dynamically executed. The program is balanced with
+ *  respect to the three aspects:
+ *
+ *    - statement type
+ *    - operand type
+ *    - operand locality
+ *         operand global, local, parameter, or constant.
+ *
+ *  The combination of these three aspects is balanced only approximately.
+ *
+ *  1. Statement Type:
+ *  -----------------             number
+ *
+ *     V1 = V2                     9
+ *       (incl. V1 = F(..)
+ *     V = Constant               12
+ *     Assignment,                 7
+ *       with array element
+ *     Assignment,                 6
+ *       with record component
+ *                                --
+ *                                34       34
+ *
+ *     X = Y +|-|"&&"|"|" Z        5
+ *     X = Y +|-|"==" Constant     6
+ *     X = X +|- 1                 3
+ *     X = Y *|/ Z                 2
+ *     X = Expression,             1
+ *           two operators
+ *     X = Expression,             1
+ *           three operators
+ *                                --
+ *                                18       18
+ *
+ *     if ....                    14
+ *       with "else"      7
+ *       without "else"   7
+ *           executed        3
+ *           not executed    4
+ *     for ...                     7  |  counted every time
+ *     while ...                   4  |  the loop condition
+ *     do ... while                1  |  is evaluated
+ *     switch ...                  1
+ *     break                       1
+ *     declaration with            1
+ *       initialization
+ *                                --
+ *                                34       34
+ *
+ *     P (...)  procedure call    11
+ *       user procedure      10
+ *       library procedure    1
+ *     X = F (...)
+ *             function  call      6
+ *       user function        5
+ *       library function     1
+ *                                --
+ *                                17       17
+ *                                        ---
+ *                                        103
+ *
+ *    The average number of parameters in procedure or function calls
+ *    is 1.82 (not counting the function values as implicit parameters).
+ *
+ *
+ *  2. Operators
+ *  ------------
+ *                          number    approximate
+ *                                    percentage
+ *
+ *    Arithmetic             32          50.8
+ *
+ *       +                     21          33.3
+ *       -                      7          11.1
+ *       *                      3           4.8
+ *       / (int div)            1           1.6
+ *
+ *    Comparison             27           42.8
+ *
+ *       ==                     9           14.3
+ *       /=                     4            6.3
+ *       >                      1            1.6
+ *       <                      3            4.8
+ *       >=                     1            1.6
+ *       <=                     9           14.3
+ *
+ *    Logic                   4            6.3
+ *
+ *       && (AND-THEN)          1            1.6
+ *       |  (OR)                1            1.6
+ *       !  (NOT)               2            3.2
+ *
+ *                           --          -----
+ *                           63          100.1
+ *
+ *
+ *  3. Operand Type (counted once per operand reference):
+ *  ---------------
+ *                          number    approximate
+ *                                    percentage
+ *
+ *     Integer               175        72.3 %
+ *     Character              45        18.6 %
+ *     Pointer                12         5.0 %
+ *     String30                6         2.5 %
+ *     Array                   2         0.8 %
+ *     Record                  2         0.8 %
+ *                           ---       -------
+ *                           242       100.0 %
+ *
+ *  When there is an access path leading to the final operand (e.g. a record
+ *  component), only the final data type on the access path is counted.
+ *
+ *
+ *  4. Operand Locality:
+ *  -------------------
+ *                                number    approximate
+ *                                          percentage
+ *
+ *     local variable              114        47.1 %
+ *     global variable              22         9.1 %
+ *     parameter                    45        18.6 %
+ *        value                        23         9.5 %
+ *        reference                    22         9.1 %
+ *     function result               6         2.5 %
+ *     constant                     55        22.7 %
+ *                                 ---       -------
+ *                                 242       100.0 %
+ *
+ *
+ *  The program does not compute anything meaningful, but it is syntactically
+ *  and semantically correct. All variables have a value assigned to them
+ *  before they are used as a source operand.
+ *
+ *  There has been no explicit effort to account for the effects of a
+ *  cache, or to balance the use of long or short displacements for code or
+ *  data.
+ *
+ ***************************************************************************
+ */
+
+typedef enum {
+	Ident_1,
+	Ident_2,
+	Ident_3,
+	Ident_4,
+	Ident_5
+} Enumeration;	/* for boolean and enumeration types in Ada, Pascal */
+
+/* General definitions: */
+
+typedef int One_Thirty;
+typedef int One_Fifty;
+typedef char Capital_Letter;
+typedef int Boolean;
+typedef char Str_30[31];
+typedef int Arr_1_Dim[50];
+typedef int Arr_2_Dim[50][50];
+
+typedef struct record {
+	struct record *Ptr_Comp;
+	Enumeration    Discr;
+	union {
+		struct {
+			Enumeration Enum_Comp;
+			int Int_Comp;
+			char Str_Comp[31];
+		} var_1;
+		struct {
+			Enumeration E_Comp_2;
+			char Str_2_Comp[31];
+		} var_2;
+		struct {
+			char Ch_1_Comp;
+			char Ch_2_Comp;
+		} var_3;
+	} variant;
+} Rec_Type, *Rec_Pointer;
+
+
+extern int Int_Glob;
+extern char Ch_1_Glob;
+
+void Proc_6(Enumeration  Enum_Val_Par, Enumeration *Enum_Ref_Par);
+void Proc_7(One_Fifty Int_1_Par_Val, One_Fifty Int_2_Par_Val,
+	    One_Fifty *Int_Par_Ref);
+void Proc_8(Arr_1_Dim Arr_1_Par_Ref, Arr_2_Dim Arr_2_Par_Ref,
+	    int Int_1_Par_Val, int Int_2_Par_Val);
+Enumeration Func_1(Capital_Letter Ch_1_Par_Val, Capital_Letter Ch_2_Par_Val);
+Boolean Func_2(Str_30 Str_1_Par_Ref, Str_30 Str_2_Par_Ref);
+
+int dhry(int n);
diff --git a/lib/dhry_1.c b/lib/dhry_1.c
new file mode 100644
index 000000000000..83247106824c
--- /dev/null
+++ b/lib/dhry_1.c
@@ -0,0 +1,283 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/*
+ ****************************************************************************
+ *
+ *                   "DHRYSTONE" Benchmark Program
+ *                   -----------------------------
+ *
+ *  Version:    C, Version 2.1
+ *
+ *  File:       dhry_1.c (part 2 of 3)
+ *
+ *  Date:       May 25, 1988
+ *
+ *  Author:     Reinhold P. Weicker
+ *
+ ****************************************************************************
+ */
+
+#include "dhry.h"
+
+#include <linux/ktime.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+/* Global Variables: */
+
+int Int_Glob;
+char Ch_1_Glob;
+
+static Rec_Pointer Ptr_Glob, Next_Ptr_Glob;
+static Boolean Bool_Glob;
+static char Ch_2_Glob;
+static int Arr_1_Glob[50];
+static int Arr_2_Glob[50][50];
+
+static void Proc_3(Rec_Pointer *Ptr_Ref_Par)
+/******************/
+/* executed once */
+/* Ptr_Ref_Par becomes Ptr_Glob */
+{
+	if (Ptr_Glob) {
+		/* then, executed */
+		*Ptr_Ref_Par = Ptr_Glob->Ptr_Comp;
+	}
+	Proc_7(10, Int_Glob, &Ptr_Glob->variant.var_1.Int_Comp);
+} /* Proc_3 */
+
+
+static void Proc_1(Rec_Pointer Ptr_Val_Par)
+/******************/
+/* executed once */
+{
+	Rec_Pointer Next_Record = Ptr_Val_Par->Ptr_Comp;
+						/* == Ptr_Glob_Next */
+	/* Local variable, initialized with Ptr_Val_Par->Ptr_Comp,    */
+	/* corresponds to "rename" in Ada, "with" in Pascal           */
+
+	*Ptr_Val_Par->Ptr_Comp = *Ptr_Glob;
+	Ptr_Val_Par->variant.var_1.Int_Comp = 5;
+	Next_Record->variant.var_1.Int_Comp =
+		Ptr_Val_Par->variant.var_1.Int_Comp;
+	Next_Record->Ptr_Comp = Ptr_Val_Par->Ptr_Comp;
+	Proc_3(&Next_Record->Ptr_Comp);
+	/* Ptr_Val_Par->Ptr_Comp->Ptr_Comp == Ptr_Glob->Ptr_Comp */
+	if (Next_Record->Discr == Ident_1) {
+		/* then, executed */
+		Next_Record->variant.var_1.Int_Comp = 6;
+		Proc_6(Ptr_Val_Par->variant.var_1.Enum_Comp,
+		       &Next_Record->variant.var_1.Enum_Comp);
+		Next_Record->Ptr_Comp = Ptr_Glob->Ptr_Comp;
+		Proc_7(Next_Record->variant.var_1.Int_Comp, 10,
+		       &Next_Record->variant.var_1.Int_Comp);
+	} else {
+		/* not executed */
+		*Ptr_Val_Par = *Ptr_Val_Par->Ptr_Comp;
+	}
+} /* Proc_1 */
+
+
+static void Proc_2(One_Fifty *Int_Par_Ref)
+/******************/
+/* executed once */
+/* *Int_Par_Ref == 1, becomes 4 */
+{
+	One_Fifty  Int_Loc;
+	Enumeration   Enum_Loc;
+
+	Int_Loc = *Int_Par_Ref + 10;
+	do {
+		/* executed once */
+		if (Ch_1_Glob == 'A') {
+			/* then, executed */
+			Int_Loc -= 1;
+			*Int_Par_Ref = Int_Loc - Int_Glob;
+			Enum_Loc = Ident_1;
+		} /* if */
+	} while (Enum_Loc != Ident_1); /* true */
+} /* Proc_2 */
+
+
+static void Proc_4(void)
+/*******/
+/* executed once */
+{
+	Boolean Bool_Loc;
+
+	Bool_Loc = Ch_1_Glob == 'A';
+	Bool_Glob = Bool_Loc | Bool_Glob;
+	Ch_2_Glob = 'B';
+} /* Proc_4 */
+
+
+static void Proc_5(void)
+/*******/
+/* executed once */
+{
+	Ch_1_Glob = 'A';
+	Bool_Glob = false;
+} /* Proc_5 */
+
+
+int dhry(int n)
+/*****/
+
+  /* main program, corresponds to procedures        */
+  /* Main and Proc_0 in the Ada version             */
+{
+	One_Fifty Int_1_Loc;
+	One_Fifty Int_2_Loc;
+	One_Fifty Int_3_Loc;
+	char Ch_Index;
+	Enumeration Enum_Loc;
+	Str_30 Str_1_Loc;
+	Str_30 Str_2_Loc;
+	int Run_Index;
+	int Number_Of_Runs;
+	ktime_t Begin_Time, End_Time;
+	u32 User_Time;
+
+	/* Initializations */
+
+	Next_Ptr_Glob = (Rec_Pointer)kzalloc(sizeof(Rec_Type), GFP_KERNEL);
+	Ptr_Glob = (Rec_Pointer)kzalloc(sizeof(Rec_Type), GFP_KERNEL);
+
+	Ptr_Glob->Ptr_Comp = Next_Ptr_Glob;
+	Ptr_Glob->Discr = Ident_1;
+	Ptr_Glob->variant.var_1.Enum_Comp = Ident_3;
+	Ptr_Glob->variant.var_1.Int_Comp = 40;
+	strcpy(Ptr_Glob->variant.var_1.Str_Comp,
+	       "DHRYSTONE PROGRAM, SOME STRING");
+	strcpy(Str_1_Loc, "DHRYSTONE PROGRAM, 1'ST STRING");
+
+	Arr_2_Glob[8][7] = 10;
+	/* Was missing in published program. Without this statement,    */
+	/* Arr_2_Glob[8][7] would have an undefined value.             */
+	/* Warning: With 16-Bit processors and Number_Of_Runs > 32000,  */
+	/* overflow may occur for this array element.                   */
+
+	pr_debug("Dhrystone Benchmark, Version 2.1 (Language: C)\n");
+
+	Number_Of_Runs = n;
+
+	pr_debug("Execution starts, %d runs through Dhrystone\n",
+		 Number_Of_Runs);
+
+	/***************/
+	/* Start timer */
+	/***************/
+
+	Begin_Time = ktime_get();
+
+	for (Run_Index = 1; Run_Index <= Number_Of_Runs; ++Run_Index) {
+		Proc_5();
+		Proc_4();
+		/* Ch_1_Glob == 'A', Ch_2_Glob == 'B', Bool_Glob == true */
+		Int_1_Loc = 2;
+		Int_2_Loc = 3;
+		strcpy(Str_2_Loc, "DHRYSTONE PROGRAM, 2'ND STRING");
+		Enum_Loc = Ident_2;
+		Bool_Glob = !Func_2(Str_1_Loc, Str_2_Loc);
+		/* Bool_Glob == 1 */
+		while (Int_1_Loc < Int_2_Loc) {
+			/* loop body executed once */
+			Int_3_Loc = 5 * Int_1_Loc - Int_2_Loc;
+			/* Int_3_Loc == 7 */
+			Proc_7(Int_1_Loc, Int_2_Loc, &Int_3_Loc);
+			/* Int_3_Loc == 7 */
+			Int_1_Loc += 1;
+		} /* while */
+		/* Int_1_Loc == 3, Int_2_Loc == 3, Int_3_Loc == 7 */
+		Proc_8(Arr_1_Glob, Arr_2_Glob, Int_1_Loc, Int_3_Loc);
+		/* Int_Glob == 5 */
+		Proc_1(Ptr_Glob);
+		for (Ch_Index = 'A'; Ch_Index <= Ch_2_Glob; ++Ch_Index) {
+			/* loop body executed twice */
+			if (Enum_Loc == Func_1(Ch_Index, 'C')) {
+				/* then, not executed */
+				Proc_6(Ident_1, &Enum_Loc);
+				strcpy(Str_2_Loc, "DHRYSTONE PROGRAM, 3'RD STRING");
+				Int_2_Loc = Run_Index;
+				Int_Glob = Run_Index;
+			}
+		}
+		/* Int_1_Loc == 3, Int_2_Loc == 3, Int_3_Loc == 7 */
+		Int_2_Loc = Int_2_Loc * Int_1_Loc;
+		Int_1_Loc = Int_2_Loc / Int_3_Loc;
+		Int_2_Loc = 7 * (Int_2_Loc - Int_3_Loc) - Int_1_Loc;
+		/* Int_1_Loc == 1, Int_2_Loc == 13, Int_3_Loc == 7 */
+		Proc_2(&Int_1_Loc);
+		/* Int_1_Loc == 5 */
+
+	} /* loop "for Run_Index" */
+
+	/**************/
+	/* Stop timer */
+	/**************/
+
+	End_Time = ktime_get();
+
+#define dhry_assert_int_eq(val, expected)				\
+	if (val != expected)						\
+		pr_err("%s: %d (FAIL, expected %d)\n", #val, val,	\
+		       expected);					\
+	else								\
+		pr_debug("%s: %d (OK)\n", #val, val)
+
+#define dhry_assert_char_eq(val, expected)				\
+	if (val != expected)						\
+		pr_err("%s: %c (FAIL, expected %c)\n", #val, val,	\
+		       expected);					\
+	else								\
+		pr_debug("%s: %c (OK)\n", #val, val)
+
+#define dhry_assert_string_eq(val, expected)				\
+	if (strcmp(val, expected))					\
+		pr_err("%s: %s (FAIL, expected %s)\n", #val, val,	\
+		       expected);					\
+	else								\
+		pr_debug("%s: %s (OK)\n", #val, val)
+
+	pr_debug("Execution ends\n");
+	pr_debug("Final values of the variables used in the benchmark:\n");
+	dhry_assert_int_eq(Int_Glob, 5);
+	dhry_assert_int_eq(Bool_Glob, 1);
+	dhry_assert_char_eq(Ch_1_Glob, 'A');
+	dhry_assert_char_eq(Ch_2_Glob, 'B');
+	dhry_assert_int_eq(Arr_1_Glob[8], 7);
+	dhry_assert_int_eq(Arr_2_Glob[8][7], Number_Of_Runs + 10);
+	pr_debug("Ptr_Comp: %px\n", Ptr_Glob->Ptr_Comp);
+	dhry_assert_int_eq(Ptr_Glob->Discr, 0);
+	dhry_assert_int_eq(Ptr_Glob->variant.var_1.Enum_Comp, 2);
+	dhry_assert_int_eq(Ptr_Glob->variant.var_1.Int_Comp, 17);
+	dhry_assert_string_eq(Ptr_Glob->variant.var_1.Str_Comp,
+			      "DHRYSTONE PROGRAM, SOME STRING");
+	if (Next_Ptr_Glob->Ptr_Comp != Ptr_Glob->Ptr_Comp)
+		pr_err("Next_Ptr_Glob->Ptr_Comp: %px (expected %px)\n",
+		       Next_Ptr_Glob->Ptr_Comp, Ptr_Glob->Ptr_Comp);
+	else
+		pr_debug("Next_Ptr_Glob->Ptr_Comp: %px\n",
+			 Next_Ptr_Glob->Ptr_Comp);
+	dhry_assert_int_eq(Next_Ptr_Glob->Discr, 0);
+	dhry_assert_int_eq(Next_Ptr_Glob->variant.var_1.Enum_Comp, 1);
+	dhry_assert_int_eq(Next_Ptr_Glob->variant.var_1.Int_Comp, 18);
+	dhry_assert_string_eq(Next_Ptr_Glob->variant.var_1.Str_Comp,
+			      "DHRYSTONE PROGRAM, SOME STRING");
+	dhry_assert_int_eq(Int_1_Loc, 5);
+	dhry_assert_int_eq(Int_2_Loc, 13);
+	dhry_assert_int_eq(Int_3_Loc, 7);
+	dhry_assert_int_eq(Enum_Loc, 1);
+	dhry_assert_string_eq(Str_1_Loc, "DHRYSTONE PROGRAM, 1'ST STRING");
+	dhry_assert_string_eq(Str_2_Loc, "DHRYSTONE PROGRAM, 2'ND STRING");
+
+	User_Time = ktime_to_ms(ktime_sub(End_Time, Begin_Time));
+
+	kfree(Ptr_Glob);
+	kfree(Next_Ptr_Glob);
+
+	/* Measurements should last at least 2 seconds */
+	if (User_Time < 2 * MSEC_PER_SEC)
+		return -EAGAIN;
+
+	return div_u64(mul_u32_u32(MSEC_PER_SEC, Number_Of_Runs), User_Time);
+}
diff --git a/lib/dhry_2.c b/lib/dhry_2.c
new file mode 100644
index 000000000000..c19e661f37d3
--- /dev/null
+++ b/lib/dhry_2.c
@@ -0,0 +1,175 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/*
+ ****************************************************************************
+ *
+ *                   "DHRYSTONE" Benchmark Program
+ *                   -----------------------------
+ *
+ *  Version:    C, Version 2.1
+ *
+ *  File:       dhry_2.c (part 3 of 3)
+ *
+ *  Date:       May 25, 1988
+ *
+ *  Author:     Reinhold P. Weicker
+ *
+ ****************************************************************************
+ */
+
+#include "dhry.h"
+
+#include <linux/string.h>
+
+
+static Boolean Func_3(Enumeration Enum_Par_Val)
+/***************************/
+/* executed once        */
+/* Enum_Par_Val == Ident_3 */
+{
+	Enumeration Enum_Loc;
+
+	Enum_Loc = Enum_Par_Val;
+	if (Enum_Loc == Ident_3) {
+		/* then, executed */
+		return true;
+	} else {
+		/* not executed */
+		return false;
+	}
+} /* Func_3 */
+
+
+void Proc_6(Enumeration  Enum_Val_Par, Enumeration *Enum_Ref_Par)
+/*********************************/
+/* executed once */
+/* Enum_Val_Par == Ident_3, Enum_Ref_Par becomes Ident_2 */
+{
+	*Enum_Ref_Par = Enum_Val_Par;
+	if (!Func_3(Enum_Val_Par)) {
+		/* then, not executed */
+		*Enum_Ref_Par = Ident_4;
+	}
+	switch (Enum_Val_Par) {
+	case Ident_1:
+		*Enum_Ref_Par = Ident_1;
+		break;
+	case Ident_2:
+		if (Int_Glob > 100) {
+			/* then */
+			*Enum_Ref_Par = Ident_1;
+		} else {
+			*Enum_Ref_Par = Ident_4;
+		}
+		break;
+	case Ident_3: /* executed */
+		*Enum_Ref_Par = Ident_2;
+		break;
+	case Ident_4:
+		break;
+	case Ident_5:
+		*Enum_Ref_Par = Ident_3;
+		break;
+	} /* switch */
+} /* Proc_6 */
+
+
+void Proc_7(One_Fifty Int_1_Par_Val, One_Fifty Int_2_Par_Val, One_Fifty *Int_Par_Ref)
+/**********************************************/
+/* executed three times                                      */
+/* first call:      Int_1_Par_Val == 2, Int_2_Par_Val == 3,  */
+/*                  Int_Par_Ref becomes 7                    */
+/* second call:     Int_1_Par_Val == 10, Int_2_Par_Val == 5, */
+/*                  Int_Par_Ref becomes 17                   */
+/* third call:      Int_1_Par_Val == 6, Int_2_Par_Val == 10, */
+/*                  Int_Par_Ref becomes 18                   */
+{
+	One_Fifty Int_Loc;
+
+	Int_Loc = Int_1_Par_Val + 2;
+	*Int_Par_Ref = Int_2_Par_Val + Int_Loc;
+} /* Proc_7 */
+
+
+void Proc_8(Arr_1_Dim Arr_1_Par_Ref, Arr_2_Dim Arr_2_Par_Ref, int Int_1_Par_Val, int Int_2_Par_Val)
+/*********************************************************************/
+/* executed once      */
+/* Int_Par_Val_1 == 3 */
+/* Int_Par_Val_2 == 7 */
+{
+	One_Fifty Int_Index;
+	One_Fifty Int_Loc;
+
+	Int_Loc = Int_1_Par_Val + 5;
+	Arr_1_Par_Ref[Int_Loc] = Int_2_Par_Val;
+	Arr_1_Par_Ref[Int_Loc+1] = Arr_1_Par_Ref[Int_Loc];
+	Arr_1_Par_Ref[Int_Loc+30] = Int_Loc;
+	for (Int_Index = Int_Loc; Int_Index <= Int_Loc+1; ++Int_Index)
+		Arr_2_Par_Ref[Int_Loc][Int_Index] = Int_Loc;
+	Arr_2_Par_Ref[Int_Loc][Int_Loc-1] += 1;
+	Arr_2_Par_Ref[Int_Loc+20][Int_Loc] = Arr_1_Par_Ref[Int_Loc];
+	Int_Glob = 5;
+} /* Proc_8 */
+
+
+Enumeration Func_1(Capital_Letter Ch_1_Par_Val, Capital_Letter Ch_2_Par_Val)
+/*************************************************/
+/* executed three times                                         */
+/* first call:      Ch_1_Par_Val == 'H', Ch_2_Par_Val == 'R'    */
+/* second call:     Ch_1_Par_Val == 'A', Ch_2_Par_Val == 'C'    */
+/* third call:      Ch_1_Par_Val == 'B', Ch_2_Par_Val == 'C'    */
+{
+	Capital_Letter Ch_1_Loc;
+	Capital_Letter Ch_2_Loc;
+
+	Ch_1_Loc = Ch_1_Par_Val;
+	Ch_2_Loc = Ch_1_Loc;
+	if (Ch_2_Loc != Ch_2_Par_Val) {
+		/* then, executed */
+		return Ident_1;
+	} else {
+		/* not executed */
+		Ch_1_Glob = Ch_1_Loc;
+		return Ident_2;
+	}
+} /* Func_1 */
+
+
+Boolean Func_2(Str_30 Str_1_Par_Ref, Str_30 Str_2_Par_Ref)
+/*************************************************/
+/* executed once */
+/* Str_1_Par_Ref == "DHRYSTONE PROGRAM, 1'ST STRING" */
+/* Str_2_Par_Ref == "DHRYSTONE PROGRAM, 2'ND STRING" */
+{
+	One_Thirty Int_Loc;
+	Capital_Letter Ch_Loc;
+
+	Int_Loc = 2;
+	while (Int_Loc <= 2) {
+		/* loop body executed once */
+		if (Func_1(Str_1_Par_Ref[Int_Loc],
+			   Str_2_Par_Ref[Int_Loc+1]) == Ident_1) {
+			/* then, executed */
+			Ch_Loc = 'A';
+			Int_Loc += 1;
+		}
+	} /* if, while */
+	if (Ch_Loc >= 'W' && Ch_Loc < 'Z') {
+		/* then, not executed */
+		Int_Loc = 7;
+	}
+	if (Ch_Loc == 'R') {
+		/* then, not executed */
+		return true;
+	} else {
+		/* executed */
+		if (strcmp(Str_1_Par_Ref, Str_2_Par_Ref) > 0) {
+			/* then, not executed */
+			Int_Loc += 7;
+			Int_Glob = Int_Loc;
+			return true;
+		} else {
+			/* executed */
+			return false;
+		}
+	} /* if Ch_Loc */
+} /* Func_2 */
diff --git a/lib/dhry_run.c b/lib/dhry_run.c
new file mode 100644
index 000000000000..f9d33efa6d09
--- /dev/null
+++ b/lib/dhry_run.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Dhrystone benchmark test module
+ *
+ * Copyright (C) 2022 Glider bv
+ */
+
+#include "dhry.h"
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/mutex.h>
+#include <linux/smp.h>
+
+#define DHRY_VAX	1757
+
+static int dhry_run_set(const char *val, const struct kernel_param *kp);
+static const struct kernel_param_ops run_ops = {
+	.flags = KERNEL_PARAM_OPS_FL_NOARG,
+	.set = dhry_run_set,
+};
+static bool dhry_run;
+module_param_cb(run, &run_ops, &dhry_run, 0200);
+MODULE_PARM_DESC(run, "Run the test (default: false)");
+
+static int iterations = -1;
+module_param(iterations, int, 0644);
+MODULE_PARM_DESC(iterations,
+		"Number of iterations through the benchmark (default: auto)");
+
+static void dhry_benchmark(void)
+{
+	int i, n;
+
+	if (iterations > 0) {
+		n = dhry(iterations);
+		goto report;
+	}
+
+	for (i = DHRY_VAX; i > 0; i <<= 1) {
+		n = dhry(i);
+		if (n != -EAGAIN)
+			break;
+	}
+
+report:
+	if (n >= 0)
+		pr_info("CPU%u: Dhrystones per Second: %d (%d DMIPS)\n",
+			smp_processor_id(), n, n / DHRY_VAX);
+	else if (n == -EAGAIN)
+		pr_err("Please increase the number of iterations\n");
+	else
+		pr_err("Dhrystone benchmark failed error %pe\n", ERR_PTR(n));
+}
+
+static int dhry_run_set(const char *val, const struct kernel_param *kp)
+{
+	int ret;
+
+	if (val) {
+		ret = param_set_bool(val, kp);
+		if (ret)
+			return ret;
+	} else {
+		dhry_run = true;
+	}
+
+	if (dhry_run && system_state == SYSTEM_RUNNING)
+		dhry_benchmark();
+
+	return 0;
+}
+
+static int __init dhry_init(void)
+{
+	if (dhry_run)
+		dhry_benchmark();
+
+	return 0;
+}
+module_init(dhry_init);
+
+MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
+MODULE_LICENSE("GPL");
diff --git a/lib/error-inject.c b/lib/error-inject.c
index 1afca1b1cdea..32c14770508e 100644
--- a/lib/error-inject.c
+++ b/lib/error-inject.c
@@ -40,7 +40,7 @@ bool within_error_injection_list(unsigned long addr)
 int get_injectable_error_type(unsigned long addr)
 {
 	struct ei_entry *ent;
-	int ei_type = EI_ETYPE_NONE;
+	int ei_type = -EINVAL;
 
 	mutex_lock(&ei_mutex);
 	list_for_each_entry(ent, &error_injection_list, list) {
diff --git a/lib/genalloc.c b/lib/genalloc.c
index 00fc50d0a640..0c883d6fbd44 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -40,32 +40,30 @@ static inline size_t chunk_size(const struct gen_pool_chunk *chunk)
 	return chunk->end_addr - chunk->start_addr + 1;
 }
 
-static int set_bits_ll(unsigned long *addr, unsigned long mask_to_set)
+static inline int
+set_bits_ll(unsigned long *addr, unsigned long mask_to_set)
 {
-	unsigned long val, nval;
+	unsigned long val = READ_ONCE(*addr);
 
-	nval = *addr;
 	do {
-		val = nval;
 		if (val & mask_to_set)
 			return -EBUSY;
 		cpu_relax();
-	} while ((nval = cmpxchg(addr, val, val | mask_to_set)) != val);
+	} while (!try_cmpxchg(addr, &val, val | mask_to_set));
 
 	return 0;
 }
 
-static int clear_bits_ll(unsigned long *addr, unsigned long mask_to_clear)
+static inline int
+clear_bits_ll(unsigned long *addr, unsigned long mask_to_clear)
 {
-	unsigned long val, nval;
+	unsigned long val = READ_ONCE(*addr);
 
-	nval = *addr;
 	do {
-		val = nval;
 		if ((val & mask_to_clear) != mask_to_clear)
 			return -EBUSY;
 		cpu_relax();
-	} while ((nval = cmpxchg(addr, val, val & ~mask_to_clear)) != val);
+	} while (!try_cmpxchg(addr, &val, val & ~mask_to_clear));
 
 	return 0;
 }
diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c
index 42f729c8e56c..dba56c5c1837 100644
--- a/lib/percpu_counter.c
+++ b/lib/percpu_counter.c
@@ -73,28 +73,33 @@ void percpu_counter_set(struct percpu_counter *fbc, s64 amount)
 EXPORT_SYMBOL(percpu_counter_set);
 
 /*
- * This function is both preempt and irq safe. The former is due to explicit
- * preemption disable. The latter is guaranteed by the fact that the slow path
- * is explicitly protected by an irq-safe spinlock whereas the fast patch uses
- * this_cpu_add which is irq-safe by definition. Hence there is no need muck
- * with irq state before calling this one
+ * local_irq_save() is needed to make the function irq safe:
+ * - The slow path would be ok as protected by an irq-safe spinlock.
+ * - this_cpu_add would be ok as it is irq-safe by definition.
+ * But:
+ * The decision slow path/fast path and the actual update must be atomic, too.
+ * Otherwise a call in process context could check the current values and
+ * decide that the fast path can be used. If now an interrupt occurs before
+ * the this_cpu_add(), and the interrupt updates this_cpu(*fbc->counters),
+ * then the this_cpu_add() that is executed after the interrupt has completed
+ * can produce values larger than "batch" or even overflows.
  */
 void percpu_counter_add_batch(struct percpu_counter *fbc, s64 amount, s32 batch)
 {
 	s64 count;
+	unsigned long flags;
 
-	preempt_disable();
+	local_irq_save(flags);
 	count = __this_cpu_read(*fbc->counters) + amount;
 	if (abs(count) >= batch) {
-		unsigned long flags;
-		raw_spin_lock_irqsave(&fbc->lock, flags);
+		raw_spin_lock(&fbc->lock);
 		fbc->count += count;
 		__this_cpu_sub(*fbc->counters, count - amount);
-		raw_spin_unlock_irqrestore(&fbc->lock, flags);
+		raw_spin_unlock(&fbc->lock);
 	} else {
 		this_cpu_add(*fbc->counters, amount);
 	}
-	preempt_enable();
+	local_irq_restore(flags);
 }
 EXPORT_SYMBOL(percpu_counter_add_batch);
 
diff --git a/lib/zlib_deflate/deflate.c b/lib/zlib_deflate/deflate.c
index 8a878d0d892c..3a1d8d34182e 100644
--- a/lib/zlib_deflate/deflate.c
+++ b/lib/zlib_deflate/deflate.c
@@ -54,7 +54,7 @@
 
 /* architecture-specific bits */
 #ifdef CONFIG_ZLIB_DFLTCC
-#  include "../zlib_dfltcc/dfltcc.h"
+#  include "../zlib_dfltcc/dfltcc_deflate.h"
 #else
 #define DEFLATE_RESET_HOOK(strm) do {} while (0)
 #define DEFLATE_HOOK(strm, flush, bstate) 0
@@ -106,7 +106,7 @@ typedef struct deflate_workspace {
     deflate_state deflate_memory;
 #ifdef CONFIG_ZLIB_DFLTCC
     /* State memory for s390 hardware deflate */
-    struct dfltcc_state dfltcc_memory;
+    struct dfltcc_deflate_state dfltcc_memory;
 #endif
     Byte *window_memory;
     Pos *prev_memory;
@@ -451,17 +451,24 @@ int zlib_deflate(
     Assert(strm->avail_out > 0, "bug2");
 
     if (flush != Z_FINISH) return Z_OK;
-    if (s->noheader) return Z_STREAM_END;
 
-    /* Write the zlib trailer (adler32) */
-    putShortMSB(s, (uInt)(strm->adler >> 16));
-    putShortMSB(s, (uInt)(strm->adler & 0xffff));
+    if (!s->noheader) {
+	/* Write zlib trailer (adler32) */
+	putShortMSB(s, (uInt)(strm->adler >> 16));
+	putShortMSB(s, (uInt)(strm->adler & 0xffff));
+    }
     flush_pending(strm);
     /* If avail_out is zero, the application will call deflate again
      * to flush the rest.
      */
-    s->noheader = -1; /* write the trailer only once! */
-    return s->pending != 0 ? Z_OK : Z_STREAM_END;
+    if (!s->noheader) {
+	s->noheader = -1; /* write the trailer only once! */
+    }
+    if (s->pending == 0) {
+	Assert(s->bi_valid == 0, "bi_buf not flushed");
+	return Z_STREAM_END;
+    }
+    return Z_OK;
 }
 
 /* ========================================================================= */
diff --git a/lib/zlib_dfltcc/dfltcc.c b/lib/zlib_dfltcc/dfltcc.c
index 782f76e9d4da..ac6ac9739f5b 100644
--- a/lib/zlib_dfltcc/dfltcc.c
+++ b/lib/zlib_dfltcc/dfltcc.c
@@ -23,37 +23,18 @@ char *oesc_msg(
     }
 }
 
-void dfltcc_reset(
-    z_streamp strm,
-    uInt size
-)
-{
-    struct dfltcc_state *dfltcc_state =
-        (struct dfltcc_state *)((char *)strm->state + size);
-    struct dfltcc_qaf_param *param =
-        (struct dfltcc_qaf_param *)&dfltcc_state->param;
-
+void dfltcc_reset_state(struct dfltcc_state *dfltcc_state) {
     /* Initialize available functions */
     if (is_dfltcc_enabled()) {
-        dfltcc(DFLTCC_QAF, param, NULL, NULL, NULL, NULL, NULL);
-        memmove(&dfltcc_state->af, param, sizeof(dfltcc_state->af));
+        dfltcc(DFLTCC_QAF, &dfltcc_state->param, NULL, NULL, NULL, NULL, NULL);
+        memmove(&dfltcc_state->af, &dfltcc_state->param, sizeof(dfltcc_state->af));
     } else
         memset(&dfltcc_state->af, 0, sizeof(dfltcc_state->af));
 
     /* Initialize parameter block */
     memset(&dfltcc_state->param, 0, sizeof(dfltcc_state->param));
     dfltcc_state->param.nt = 1;
-
-    /* Initialize tuning parameters */
-    if (zlib_dfltcc_support == ZLIB_DFLTCC_FULL_DEBUG)
-        dfltcc_state->level_mask = DFLTCC_LEVEL_MASK_DEBUG;
-    else
-        dfltcc_state->level_mask = DFLTCC_LEVEL_MASK;
-    dfltcc_state->block_size = DFLTCC_BLOCK_SIZE;
-    dfltcc_state->block_threshold = DFLTCC_FIRST_FHT_BLOCK_SIZE;
-    dfltcc_state->dht_threshold = DFLTCC_DHT_MIN_SAMPLE_SIZE;
     dfltcc_state->param.ribm = DFLTCC_RIBM;
 }
-EXPORT_SYMBOL(dfltcc_reset);
 
 MODULE_LICENSE("GPL");
diff --git a/lib/zlib_dfltcc/dfltcc.h b/lib/zlib_dfltcc/dfltcc.h
index 2a2fac1d050a..b96232bdd44d 100644
--- a/lib/zlib_dfltcc/dfltcc.h
+++ b/lib/zlib_dfltcc/dfltcc.h
@@ -93,63 +93,32 @@ static_assert(sizeof(struct dfltcc_param_v0) == 1536);
 struct dfltcc_state {
     struct dfltcc_param_v0 param;      /* Parameter block */
     struct dfltcc_qaf_param af;        /* Available functions */
+    char msg[64];                      /* Buffer for strm->msg */
+};
+
+/*
+ *  Extension of inflate_state and deflate_state for DFLTCC.
+ */
+struct dfltcc_deflate_state {
+    struct dfltcc_state common;        /* Parameter block */
     uLong level_mask;                  /* Levels on which to use DFLTCC */
     uLong block_size;                  /* New block each X bytes */
     uLong block_threshold;             /* New block after total_in > X */
     uLong dht_threshold;               /* New block only if avail_in >= X */
-    char msg[64];                      /* Buffer for strm->msg */
 };
 
+#define ALIGN_UP(p, size) (__typeof__(p))(((uintptr_t)(p) + ((size) - 1)) & ~((size) - 1))
 /* Resides right after inflate_state or deflate_state */
-#define GET_DFLTCC_STATE(state) ((struct dfltcc_state *)((state) + 1))
-
-/* External functions */
-int dfltcc_can_deflate(z_streamp strm);
-int dfltcc_deflate(z_streamp strm,
-                   int flush,
-                   block_state *result);
-void dfltcc_reset(z_streamp strm, uInt size);
-int dfltcc_can_inflate(z_streamp strm);
-typedef enum {
-    DFLTCC_INFLATE_CONTINUE,
-    DFLTCC_INFLATE_BREAK,
-    DFLTCC_INFLATE_SOFTWARE,
-} dfltcc_inflate_action;
-dfltcc_inflate_action dfltcc_inflate(z_streamp strm,
-                                     int flush, int *ret);
+#define GET_DFLTCC_STATE(state) ((struct dfltcc_state *)((char *)(state) + ALIGN_UP(sizeof(*state), 8)))
+
+void dfltcc_reset_state(struct dfltcc_state *dfltcc_state);
+
 static inline int is_dfltcc_enabled(void)
 {
 return (zlib_dfltcc_support != ZLIB_DFLTCC_DISABLED &&
         test_facility(DFLTCC_FACILITY));
 }
 
-#define DEFLATE_RESET_HOOK(strm) \
-    dfltcc_reset((strm), sizeof(deflate_state))
-
-#define DEFLATE_HOOK dfltcc_deflate
-
-#define DEFLATE_NEED_CHECKSUM(strm) (!dfltcc_can_deflate((strm)))
-
 #define DEFLATE_DFLTCC_ENABLED() is_dfltcc_enabled()
 
-#define INFLATE_RESET_HOOK(strm) \
-    dfltcc_reset((strm), sizeof(struct inflate_state))
-
-#define INFLATE_TYPEDO_HOOK(strm, flush) \
-    if (dfltcc_can_inflate((strm))) { \
-        dfltcc_inflate_action action; \
-\
-        RESTORE(); \
-        action = dfltcc_inflate((strm), (flush), &ret); \
-        LOAD(); \
-        if (action == DFLTCC_INFLATE_CONTINUE) \
-            break; \
-        else if (action == DFLTCC_INFLATE_BREAK) \
-            goto inf_leave; \
-    }
-
-#define INFLATE_NEED_CHECKSUM(strm) (!dfltcc_can_inflate((strm)))
-
-#define INFLATE_NEED_UPDATEWINDOW(strm) (!dfltcc_can_inflate((strm)))
-
 #endif /* DFLTCC_H */
diff --git a/lib/zlib_dfltcc/dfltcc_deflate.c b/lib/zlib_dfltcc/dfltcc_deflate.c
index 6c946e8532ee..b732b6d9e35d 100644
--- a/lib/zlib_dfltcc/dfltcc_deflate.c
+++ b/lib/zlib_dfltcc/dfltcc_deflate.c
@@ -2,11 +2,13 @@
 
 #include "../zlib_deflate/defutil.h"
 #include "dfltcc_util.h"
-#include "dfltcc.h"
+#include "dfltcc_deflate.h"
 #include <asm/setup.h>
 #include <linux/export.h>
 #include <linux/zutil.h>
 
+#define GET_DFLTCC_DEFLATE_STATE(state) ((struct dfltcc_deflate_state *)GET_DFLTCC_STATE(state))
+
 /*
  * Compress.
  */
@@ -15,7 +17,7 @@ int dfltcc_can_deflate(
 )
 {
     deflate_state *state = (deflate_state *)strm->state;
-    struct dfltcc_state *dfltcc_state = GET_DFLTCC_STATE(state);
+    struct dfltcc_deflate_state *dfltcc_state = GET_DFLTCC_DEFLATE_STATE(state);
 
     /* Check for kernel dfltcc command line parameter */
     if (zlib_dfltcc_support == ZLIB_DFLTCC_DISABLED ||
@@ -28,22 +30,39 @@ int dfltcc_can_deflate(
         return 0;
 
     /* Unsupported hardware */
-    if (!is_bit_set(dfltcc_state->af.fns, DFLTCC_GDHT) ||
-            !is_bit_set(dfltcc_state->af.fns, DFLTCC_CMPR) ||
-            !is_bit_set(dfltcc_state->af.fmts, DFLTCC_FMT0))
+    if (!is_bit_set(dfltcc_state->common.af.fns, DFLTCC_GDHT) ||
+            !is_bit_set(dfltcc_state->common.af.fns, DFLTCC_CMPR) ||
+            !is_bit_set(dfltcc_state->common.af.fmts, DFLTCC_FMT0))
         return 0;
 
     return 1;
 }
 EXPORT_SYMBOL(dfltcc_can_deflate);
 
+void dfltcc_reset_deflate_state(z_streamp strm) {
+    deflate_state *state = (deflate_state *)strm->state;
+    struct dfltcc_deflate_state *dfltcc_state = GET_DFLTCC_DEFLATE_STATE(state);
+
+    dfltcc_reset_state(&dfltcc_state->common);
+
+    /* Initialize tuning parameters */
+    if (zlib_dfltcc_support == ZLIB_DFLTCC_FULL_DEBUG)
+        dfltcc_state->level_mask = DFLTCC_LEVEL_MASK_DEBUG;
+    else
+        dfltcc_state->level_mask = DFLTCC_LEVEL_MASK;
+    dfltcc_state->block_size = DFLTCC_BLOCK_SIZE;
+    dfltcc_state->block_threshold = DFLTCC_FIRST_FHT_BLOCK_SIZE;
+    dfltcc_state->dht_threshold = DFLTCC_DHT_MIN_SAMPLE_SIZE;
+}
+EXPORT_SYMBOL(dfltcc_reset_deflate_state);
+
 static void dfltcc_gdht(
     z_streamp strm
 )
 {
     deflate_state *state = (deflate_state *)strm->state;
     struct dfltcc_param_v0 *param = &GET_DFLTCC_STATE(state)->param;
-    size_t avail_in = avail_in = strm->avail_in;
+    size_t avail_in = strm->avail_in;
 
     dfltcc(DFLTCC_GDHT,
            param, NULL, NULL,
@@ -104,39 +123,46 @@ int dfltcc_deflate(
 )
 {
     deflate_state *state = (deflate_state *)strm->state;
-    struct dfltcc_state *dfltcc_state = GET_DFLTCC_STATE(state);
-    struct dfltcc_param_v0 *param = &dfltcc_state->param;
+    struct dfltcc_deflate_state *dfltcc_state = GET_DFLTCC_DEFLATE_STATE(state);
+    struct dfltcc_param_v0 *param = &dfltcc_state->common.param;
     uInt masked_avail_in;
     dfltcc_cc cc;
     int need_empty_block;
     int soft_bcc;
     int no_flush;
 
-    if (!dfltcc_can_deflate(strm))
+    if (!dfltcc_can_deflate(strm)) {
+        /* Clear history. */
+        if (flush == Z_FULL_FLUSH)
+            param->hl = 0;
         return 0;
+    }
 
 again:
     masked_avail_in = 0;
     soft_bcc = 0;
     no_flush = flush == Z_NO_FLUSH;
 
-    /* Trailing empty block. Switch to software, except when Continuation Flag
-     * is set, which means that DFLTCC has buffered some output in the
-     * parameter block and needs to be called again in order to flush it.
+    /* No input data. Return, except when Continuation Flag is set, which means
+     * that DFLTCC has buffered some output in the parameter block and needs to
+     * be called again in order to flush it.
      */
-    if (flush == Z_FINISH && strm->avail_in == 0 && !param->cf) {
-        if (param->bcf) {
-            /* A block is still open, and the hardware does not support closing
-             * blocks without adding data. Thus, close it manually.
-             */
+    if (strm->avail_in == 0 && !param->cf) {
+        /* A block is still open, and the hardware does not support closing
+         * blocks without adding data. Thus, close it manually.
+         */
+        if (!no_flush && param->bcf) {
             send_eobs(strm, param);
             param->bcf = 0;
         }
-        return 0;
-    }
-
-    if (strm->avail_in == 0 && !param->cf) {
-        *result = need_more;
+        /* Let one of deflate_* functions write a trailing empty block. */
+        if (flush == Z_FINISH)
+            return 0;
+        /* Clear history. */
+        if (flush == Z_FULL_FLUSH)
+            param->hl = 0;
+        /* Trigger block post-processing if necessary. */
+        *result = no_flush ? need_more : block_done;
         return 1;
     }
 
@@ -163,13 +189,18 @@ again:
             param->bcf = 0;
             dfltcc_state->block_threshold =
                 strm->total_in + dfltcc_state->block_size;
-            if (strm->avail_out == 0) {
-                *result = need_more;
-                return 1;
-            }
         }
     }
 
+    /* No space for compressed data. If we proceed, dfltcc_cmpr() will return
+     * DFLTCC_CC_OP1_TOO_SHORT without buffering header bits, but we will still
+     * set BCF=1, which is wrong. Avoid complications and return early.
+     */
+    if (strm->avail_out == 0) {
+        *result = need_more;
+        return 1;
+    }
+
     /* The caller gave us too much data. Pass only one block worth of
      * uncompressed data to DFLTCC and mask the rest, so that on the next
      * iteration we start a new block.
@@ -189,7 +220,7 @@ again:
     param->cvt = CVT_ADLER32;
     if (!no_flush)
         /* We need to close a block. Always do this in software - when there is
-         * no input data, the hardware will not nohor BCC. */
+         * no input data, the hardware will not hohor BCC. */
         soft_bcc = 1;
     if (flush == Z_FINISH && !param->bcf)
         /* We are about to open a BFINAL block, set Block Header Final bit
@@ -204,8 +235,8 @@ again:
     param->sbb = (unsigned int)state->bi_valid;
     if (param->sbb > 0)
         *strm->next_out = (Byte)state->bi_buf;
-    if (param->hl)
-        param->nt = 0; /* Honor history */
+    /* Honor history and check value */
+    param->nt = 0;
     param->cv = strm->adler;
 
     /* When opening a block, choose a Huffman-Table Type */
@@ -232,7 +263,7 @@ again:
     } while (cc == DFLTCC_CC_AGAIN);
 
     /* Translate parameter block to stream */
-    strm->msg = oesc_msg(dfltcc_state->msg, param->oesc);
+    strm->msg = oesc_msg(dfltcc_state->common.msg, param->oesc);
     state->bi_valid = param->sbb;
     if (state->bi_valid == 0)
         state->bi_buf = 0; /* Avoid accessing next_out */
diff --git a/lib/zlib_dfltcc/dfltcc_deflate.h b/lib/zlib_dfltcc/dfltcc_deflate.h
new file mode 100644
index 000000000000..be44b43833b1
--- /dev/null
+++ b/lib/zlib_dfltcc/dfltcc_deflate.h
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: Zlib
+#ifndef DFLTCC_DEFLATE_H
+#define DFLTCC_DEFLATE_H
+
+#include "dfltcc.h"
+
+/* External functions */
+int dfltcc_can_deflate(z_streamp strm);
+int dfltcc_deflate(z_streamp strm,
+                   int flush,
+                   block_state *result);
+void dfltcc_reset_deflate_state(z_streamp strm);
+
+#define DEFLATE_RESET_HOOK(strm) \
+    dfltcc_reset_deflate_state((strm))
+
+#define DEFLATE_HOOK dfltcc_deflate
+
+#define DEFLATE_NEED_CHECKSUM(strm) (!dfltcc_can_deflate((strm)))
+
+#endif /* DFLTCC_DEFLATE_H */
diff --git a/lib/zlib_dfltcc/dfltcc_inflate.c b/lib/zlib_dfltcc/dfltcc_inflate.c
index fb60b5a6a1cb..437cd34c8490 100644
--- a/lib/zlib_dfltcc/dfltcc_inflate.c
+++ b/lib/zlib_dfltcc/dfltcc_inflate.c
@@ -2,7 +2,7 @@
 
 #include "../zlib_inflate/inflate.h"
 #include "dfltcc_util.h"
-#include "dfltcc.h"
+#include "dfltcc_inflate.h"
 #include <asm/setup.h>
 #include <linux/export.h>
 #include <linux/zutil.h>
@@ -22,16 +22,20 @@ int dfltcc_can_inflate(
             zlib_dfltcc_support == ZLIB_DFLTCC_DEFLATE_ONLY)
         return 0;
 
-    /* Unsupported compression settings */
-    if (state->wbits != HB_BITS)
-        return 0;
-
     /* Unsupported hardware */
     return is_bit_set(dfltcc_state->af.fns, DFLTCC_XPND) &&
                is_bit_set(dfltcc_state->af.fmts, DFLTCC_FMT0);
 }
 EXPORT_SYMBOL(dfltcc_can_inflate);
 
+void dfltcc_reset_inflate_state(z_streamp strm) {
+    struct inflate_state *state = (struct inflate_state *)strm->state;
+    struct dfltcc_state *dfltcc_state = GET_DFLTCC_STATE(state);
+
+    dfltcc_reset_state(dfltcc_state);
+}
+EXPORT_SYMBOL(dfltcc_reset_inflate_state);
+
 static int dfltcc_was_inflate_used(
     z_streamp strm
 )
@@ -91,8 +95,10 @@ dfltcc_inflate_action dfltcc_inflate(
     struct dfltcc_param_v0 *param = &dfltcc_state->param;
     dfltcc_cc cc;
 
-    if (flush == Z_BLOCK) {
-        /* DFLTCC does not support stopping on block boundaries */
+    if (flush == Z_BLOCK || flush == Z_PACKET_FLUSH) {
+        /* DFLTCC does not support stopping on block boundaries (Z_BLOCK flush option)
+         * as well as the use of Z_PACKET_FLUSH option (used exclusively by PPP driver)
+         */
         if (dfltcc_inflate_disable(strm)) {
             *ret = Z_STREAM_ERROR;
             return DFLTCC_INFLATE_BREAK;
@@ -121,8 +127,6 @@ dfltcc_inflate_action dfltcc_inflate(
     /* Translate stream to parameter block */
     param->cvt = CVT_ADLER32;
     param->sbb = state->bits;
-    param->hl = state->whave; /* Software and hardware history formats match */
-    param->ho = (state->write - state->whave) & ((1 << HB_BITS) - 1);
     if (param->hl)
         param->nt = 0; /* Honor history for the first block */
     param->cv = state->check;
@@ -136,8 +140,6 @@ dfltcc_inflate_action dfltcc_inflate(
     strm->msg = oesc_msg(dfltcc_state->msg, param->oesc);
     state->last = cc == DFLTCC_CC_OK;
     state->bits = param->sbb;
-    state->whave = param->hl;
-    state->write = (param->ho + param->hl) & ((1 << HB_BITS) - 1);
     state->check = param->cv;
     if (cc == DFLTCC_CC_OP2_CORRUPT && param->oesc != 0) {
         /* Report an error if stream is corrupted */
diff --git a/lib/zlib_dfltcc/dfltcc_inflate.h b/lib/zlib_dfltcc/dfltcc_inflate.h
new file mode 100644
index 000000000000..98d4bc42e526
--- /dev/null
+++ b/lib/zlib_dfltcc/dfltcc_inflate.h
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: Zlib
+#ifndef DFLTCC_INFLATE_H
+#define DFLTCC_INFLATE_H
+
+#include "dfltcc.h"
+
+/* External functions */
+void dfltcc_reset_inflate_state(z_streamp strm);
+int dfltcc_can_inflate(z_streamp strm);
+typedef enum {
+    DFLTCC_INFLATE_CONTINUE,
+    DFLTCC_INFLATE_BREAK,
+    DFLTCC_INFLATE_SOFTWARE,
+} dfltcc_inflate_action;
+dfltcc_inflate_action dfltcc_inflate(z_streamp strm,
+                                     int flush, int *ret);
+#define INFLATE_RESET_HOOK(strm) \
+    dfltcc_reset_inflate_state((strm))
+
+#define INFLATE_TYPEDO_HOOK(strm, flush) \
+    if (dfltcc_can_inflate((strm))) { \
+        dfltcc_inflate_action action; \
+\
+        RESTORE(); \
+        action = dfltcc_inflate((strm), (flush), &ret); \
+        LOAD(); \
+        if (action == DFLTCC_INFLATE_CONTINUE) \
+            break; \
+        else if (action == DFLTCC_INFLATE_BREAK) \
+            goto inf_leave; \
+    }
+
+#define INFLATE_NEED_CHECKSUM(strm) (!dfltcc_can_inflate((strm)))
+
+#define INFLATE_NEED_UPDATEWINDOW(strm) (!dfltcc_can_inflate((strm)))
+
+#endif /* DFLTCC_DEFLATE_H */
diff --git a/lib/zlib_inflate/inflate.c b/lib/zlib_inflate/inflate.c
index ee39b5eb71f7..d1efad69f02b 100644
--- a/lib/zlib_inflate/inflate.c
+++ b/lib/zlib_inflate/inflate.c
@@ -17,7 +17,7 @@
 
 /* architecture-specific bits */
 #ifdef CONFIG_ZLIB_DFLTCC
-#  include "../zlib_dfltcc/dfltcc.h"
+#  include "../zlib_dfltcc/dfltcc_inflate.h"
 #else
 #define INFLATE_RESET_HOOK(strm) do {} while (0)
 #define INFLATE_TYPEDO_HOOK(strm, flush) do {} while (0)