diff --git a/01_git/.gitignore b/01_git/.gitignore
new file mode 100644
index 0000000..92e163a
--- /dev/null
+++ b/01_git/.gitignore
@@ -0,0 +1,3 @@
+*.out
+*.json
+game
diff --git a/01_git/scissors/Makefile b/01_git/scissors/Makefile
new file mode 100644
index 0000000..5631a8f
--- /dev/null
+++ b/01_git/scissors/Makefile
@@ -0,0 +1,20 @@
+CXX=g++
+CXX_FLAGS=-std=c++11 -O3 -Wall -Werror -Wpedantic
+INC=-I.
+LDFLAGS=-lcrypto
+
+CXX_SOURCES=choice.cpp game.cpp
+OUT_NAME=game
+
+RM=rm -rf
+
+# The project is tiny so do clean build at all times
+# to suppress $TARGET is up to date" in case we're
+# updating the module.
+game: clean
+	$(CXX) $(CXX_FLAGS) $(INC) $(CXX_SOURCES) -o$@ $(LDFLAGS)
+
+all: game
+
+clean:
+	$(RM) $(OUT_NAME)
diff --git a/01_git/scissors/choice.cpp b/01_git/scissors/choice.cpp
new file mode 100644
index 0000000..1e28b80
--- /dev/null
+++ b/01_git/scissors/choice.cpp
@@ -0,0 +1,150 @@
+#include "choice.h"
+
+#include <iostream>
+#include <cassert>
+#include <cstring>
+
+#include <openssl/md5.h>
+
+namespace
+{
+
+const char* const gaItemsStrRepr[]
+{
+    "scissors", // SCISSORS
+    "paper",    // PAPER
+    "rock"      // ROCK
+};
+
+} //namespace
+
+namespace game
+{
+// Auxiliary stuff.
+
+CVal decodeChoiceStdin(char rdRawChoice)
+{
+    switch (std::tolower(rdRawChoice))
+    {
+    // In-game items.
+    case 's':
+        return CVal::SCISSORS;
+    case 'p':
+        return CVal::PAPER;
+    case 'r':
+        return CVal::ROCK;
+
+    // Control codes.
+    case 'q':
+    // FALLTHROUGH
+    case EOF:
+    // FALLTHROUGH
+    case 0: // ^D - a corner-case for std::cin! In case ^D is pressed
+            // we get into an infinite loop.
+        return CVal::QUIT;
+    case '\n':
+    // FALLTHROUGH
+    case '\r':
+        return CVal::IGNORE;
+
+    default:
+        return CVal::CHOICE_LAST;
+    }
+}
+
+CVal decodeChoiceInt(int rdRawChoice)
+{
+    for (auto i = Choice::ToInt(CVal::SCISSORS);
+            i < Choice::ToInt(CVal::CHOICE_LAST); ++i)
+    {
+        if (i == rdRawChoice)
+        {
+            return static_cast<CVal>(i);
+        }
+    }
+
+    return CVal::CHOICE_LAST;
+}
+
+// Choice class impl.
+
+const char* const Choice::ToString(CVal reValue)
+{
+    assert(reValue < CVal::CHOICE_LAST);
+    return gaItemsStrRepr[ToInt(reValue)];
+}
+
+void Choice::PrintMd5FromChoice(CVal reValue)
+{
+    assert(reValue < CVal::CHOICE_LAST);
+    const auto pChoiceString = ToString(reValue);
+    const auto dChoiceLength = std::strlen(pChoiceString);
+
+    unsigned char aDigest[MD5_DIGEST_LENGTH] {};
+    const auto pDigest = MD5(reinterpret_cast<const unsigned char*>(pChoiceString),
+                             dChoiceLength, aDigest);
+    std::cout << "MD5(choice): 0x";
+    for (size_t i = 0; i < sizeof(aDigest); ++i)
+    {
+        std::cout << std::hex << short(pDigest[i]);
+    }
+
+    std::cout << std::endl;
+}
+
+// ChoiceStdin class impl.
+
+CVal ChoiceStdin::Get()
+{
+    bool bSkipHeading = false;
+
+    while (true)
+    {
+        if (not bSkipHeading)
+        {
+            std::cout << "Please choose: rock (r) - paper (p) - scissors (s)" << std::endl;
+        }
+        else
+        {
+            bSkipHeading = false;
+        }
+
+        auto dInput = '\0';
+        std::cin >> dInput;
+        const auto eChoice {decodeChoiceStdin(dInput)};
+
+        if (eChoice == CVal::IGNORE)
+        {
+            // Eat up LFs and CRs, do not repeat the prompt above.
+            bSkipHeading = true;
+            continue;
+        }
+
+        if (eChoice == CVal::CHOICE_LAST)
+        {
+            std::cout << "Wrong input";
+            if (std::isalnum(dInput))
+            {
+                // Check letters & numbers only, do not overcomplicate things.
+                std::cout << ": " << char(dInput);
+            }
+
+            std::cout << "!" << std::endl << "Press 'q' or '^C'/'^D' to exit" << std::endl;
+            continue;
+        }
+
+        return eChoice;
+    }
+}
+
+// ChoiceRandom class impl.
+
+CVal ChoiceRandom::Get()
+{
+    const auto eChoice = decodeChoiceInt(mtUniDistr(mtRandSrc));
+    assert(eChoice != CVal::CHOICE_LAST); // Double-checking UniDistr range.
+    PrintMd5FromChoice(eChoice);
+    return eChoice;
+}
+
+} // namespace game
diff --git a/01_git/scissors/choice.h b/01_git/scissors/choice.h
new file mode 100644
index 0000000..ae332c9
--- /dev/null
+++ b/01_git/scissors/choice.h
@@ -0,0 +1,69 @@
+#pragma once
+
+#include <random>
+
+namespace game
+{
+
+class Choice
+{
+public:
+
+    enum class Value : int
+    {
+        // Game-related values.
+        SCISSORS = 0,
+        PAPER,
+        ROCK,
+
+        // Enum size & invalid input marker.
+        CHOICE_LAST,
+        // Crutch to skip some control chars, like CR & LF
+        IGNORE,
+        // "game quit" choice.
+        QUIT
+    };
+
+    virtual Value Get() = 0;
+
+    static constexpr int ToInt(Value reValue)
+    {
+        return static_cast<int>(reValue);
+    }
+
+    static const char* const ToString(Value reValue);
+    static void PrintMd5FromChoice(Value reValue);
+
+};
+
+using CVal = Choice::Value;
+
+class ChoiceStdin : public Choice
+{
+public:
+
+    Value Get() override;
+};
+
+class ChoiceRandom : public Choice
+{
+    using UniDistr = std::uniform_int_distribution<>;
+
+public:
+
+    ChoiceRandom() :
+        mtUniDistr(ToInt(CVal::SCISSORS), ToInt(CVal::ROCK))
+    {
+        std::random_device tDrbg;
+        mtRandSrc.seed(tDrbg());
+    }
+
+    Value Get() override;
+
+private:
+
+    std::mt19937 mtRandSrc;
+    UniDistr mtUniDistr;
+};
+
+} // namespace game
diff --git a/01_git/scissors/game.cpp b/01_git/scissors/game.cpp
new file mode 100644
index 0000000..4fbc1a1
--- /dev/null
+++ b/01_git/scissors/game.cpp
@@ -0,0 +1,79 @@
+#include "choice.h"
+
+#include <iostream>
+
+enum class Result : int
+{
+    PLAYER_WINS = 0,
+    CPU_WINS,
+    DRAW
+};
+
+using namespace game;
+
+namespace
+{
+
+const char* const gaGameResStrRepr[]
+{
+    "You win", // PLAYER_WINS
+    "I win",   // CPU_WINS
+    "Draw!"    // DRAW
+};
+
+const Result gaResolveTbl[][Choice::ToInt(CVal::CHOICE_LAST)]
+{
+    //      SCISSORS        |        PAPER         |     ROCK           <- Player's choice
+    //
+    //                                                                       CPU's choice
+    //                                                                             |
+    //                                                                             V
+    {    Result::DRAW,        Result::PLAYER_WINS,     Result::CPU_WINS    },  // SCISSORS
+    {  Result::CPU_WINS,         Result::DRAW,        Result::PLAYER_WINS  },  // PAPER
+    {  Result::PLAYER_WINS,    Result::CPU_WINS,         Result::DRAW      }   // ROCK
+};
+
+void resolveGame(CVal rePlayerChoice, CVal reCpuChoice)
+{
+    const auto eResult = gaResolveTbl
+        [Choice::ToInt(rePlayerChoice)]
+        [Choice::ToInt(reCpuChoice)];
+
+    std::cout << gaGameResStrRepr[static_cast<int>(eResult)];
+
+    if (eResult != Result::DRAW)
+    {
+        const auto eFirstNoun = (eResult == Result::CPU_WINS) ? reCpuChoice : rePlayerChoice;
+        const auto eSecondNoun = (eFirstNoun == reCpuChoice) ? rePlayerChoice : reCpuChoice;
+        std::cout << ": " << Choice::ToString(eFirstNoun);
+        std::cout << " beat" << (eFirstNoun != CVal::SCISSORS ? "s" : "");
+        std::cout << " " << Choice::ToString(eSecondNoun);
+    }
+
+    std::cout << std::endl;
+}
+} // namespace
+
+int main()
+{
+    ChoiceStdin tPlayerInput;
+    ChoiceRandom tCpuInput;
+
+    while (true)
+    {
+
+        // Make CPU's move first, we need to play fair.
+        const auto eCpuChoice = tCpuInput.Get();
+        const auto ePlayerChoice = tPlayerInput.Get();
+        if (ePlayerChoice == CVal::QUIT)
+        {
+            break;
+        }
+
+        std::cout << "You chose " << Choice::ToString(ePlayerChoice);
+        std::cout << ", I chose " << Choice::ToString(eCpuChoice) << std::endl;
+        resolveGame(ePlayerChoice, eCpuChoice);
+    }
+
+    std::cout << "Bye!" << std::endl;
+}
diff --git a/02_bash/hwdetect/hwdetect.sh b/02_bash/hwdetect/hwdetect.sh
new file mode 100755
index 0000000..e5c84ab
--- /dev/null
+++ b/02_bash/hwdetect/hwdetect.sh
@@ -0,0 +1,91 @@
+#!/bin/bash
+
+# PLEASE NOTE: the script works with bash only!
+# Other shells, like zsh are not supported.
+
+# Add other subsystems which can be tested with hotplugging to monitor.
+# Currently we listen to addition/removal of:
+# 1) USB pendrives/SD/MMC cards: mmc and block
+# 2) USB-HID devices (and generic HID devices, like PS/2? I tested with yubikey & mice only): hid
+# 3) USB-to-UART converters: usb-serial (also tty may be added)
+monitored_subsys=(block hid usb-serial mmc)
+
+temp_buf=`mktemp`
+
+for subsys in "${monitored_subsys[@]}"
+do
+    query+="--subsystem-match=$subsys "
+done
+
+udevadm monitor -k $query > $temp_buf &
+udevadm_pid=$!
+
+cleanup () {
+    kill -SIGTERM $udevadm_pid
+    rm -rf $temp_buf
+}
+
+filter() {
+    # tail + grep combo returns a single block of strings separated with
+    # spaces instead of '\n's. udevadm does not have an ability to filter
+    # events by action types by itself so, for example inserting/removing a
+    # USB device generates lots of output which contain also 'bind/unbind' actions
+    # which we consider just a noise for this task. These must be excluded
+    # from the output, so we iterate through the list of words in search
+    # for the given tag (like 'add' or 'remove'); in case one is found
+    # the next token is the device name (according to udevadm format). Sub-classes
+    # are filtered by --subsystem-match so we don't need to filter that lines.
+    # This also eats up [KERNEL... headers.
+    # The same could be probably achieved by awk?
+
+    local tag=$1
+    local tag_found=0
+    local input=("$@")
+
+    # Iterate from the first arg (not zero-th!)
+    # this is a crutch to suppress garbage in output
+    for line in "${input[@]:1}";
+    do
+        if [ $tag_found -eq 0 ];
+        then
+            if [ "$tag" == "$line" ];
+            then
+                tag_found=1
+            fi
+        else
+            echo $line
+            tag_found=0
+        fi
+    done
+}
+
+trap cleanup EXIT SIGTERM
+
+read_pos=0
+
+while : ;
+do
+    diff_list=`tail -c +$read_pos $temp_buf`
+    diff_len=${#diff_list}
+    ((read_pos+=$diff_len))
+
+    # Preprocess add/remove lists in order not to
+    # filter empty input or an input which does not
+    # contain data which we're interested in.
+    added_list=`echo $diff_list | grep add`
+    removed_list=`echo $diff_list | grep remove`
+
+    if [ ! -z "${added_list}" ]; then
+        echo
+        echo Added devices:
+        filter "add" $added_list
+    fi
+
+    if [ ! -z "${removed_list}" ]; then
+        echo
+        echo Removed devices:
+        filter "remove" $removed_list
+    fi
+
+    sleep 1
+done
diff --git a/03_module/Makefile b/03_module/Makefile
new file mode 100644
index 0000000..7337fb9
--- /dev/null
+++ b/03_module/Makefile
@@ -0,0 +1,17 @@
+KDIR ?= ~/work/buildroot-2021.02.7/output/build/linux-5.10.7
+CHECKPATCH := $(KDIR)/scripts/checkpatch.pl
+
+SRC := argsmod.c
+OBJS := $(SRC:.c=.o)
+
+obj-m += $(OBJS)
+
+all:
+	$(CHECKPATCH) -f $(SRC) || exit 1
+	$(MAKE) -C $(KDIR) M=$(PWD) modules
+
+default: all
+
+clean:
+	$(MAKE) -C $(KDIR) M=$(PWD) clean
+
diff --git a/03_module/argsmod.c b/03_module/argsmod.c
new file mode 100644
index 0000000..6f9d69b
--- /dev/null
+++ b/03_module/argsmod.c
@@ -0,0 +1,34 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Victor Krasnoshchok <ct3da21164@protonmail.ch>");
+MODULE_DESCRIPTION("Compute sum & diff of mod's args upon init/exit.");
+MODULE_VERSION("0.1");
+
+static int first_arg;
+static int second_arg;
+
+module_param(first_arg, int, 0444); /* S_IRUGO */
+MODULE_PARM_DESC(first_arg, "The first int arg.");
+
+module_param(second_arg, int, 0444);
+MODULE_PARM_DESC(second_arg, "The second int arg.");
+
+static int __init args_test_init(void)
+{
+	pr_info("%d + %d = %d\n", first_arg, second_arg, (first_arg + second_arg));
+	return 0;
+}
+
+static void __exit args_test_exit(void)
+{
+	pr_info("%d - %d = %d\n", first_arg, second_arg, (first_arg - second_arg));
+}
+
+module_init(args_test_init);
+module_exit(args_test_exit);
+
diff --git a/03_module/compilation_log.txt b/03_module/compilation_log.txt
new file mode 100644
index 0000000..a74411b
--- /dev/null
+++ b/03_module/compilation_log.txt
@@ -0,0 +1,13 @@
+victor@orion5491  ~/work/gl_kernel_procamp_2021/03_module   task03  make
+~/work/buildroot-2021.02.7/output/build/linux-5.10.7/scripts/checkpatch.pl -f argsmod.c || exit 1
+total: 0 errors, 0 warnings, 34 lines checked
+
+argsmod.c has no obvious style problems and is ready for submission.
+make -C ~/work/buildroot-2021.02.7/output/build/linux-5.10.7 M=/home/victor/work/gl_kernel_procamp_2021/03_module modules
+make[1]: Entering directory '/home/victor/work/buildroot-2021.02.7/output/build/linux-5.10.7'
+  CC [M]  /home/victor/work/gl_kernel_procamp_2021/03_module/argsmod.o
+  MODPOST /home/victor/work/gl_kernel_procamp_2021/03_module/Module.symvers
+WARNING: modpost: Symbol info of vmlinux is missing. Unresolved symbol check will be entirely skipped.
+  CC [M]  /home/victor/work/gl_kernel_procamp_2021/03_module/argsmod.mod.o
+  LD [M]  /home/victor/work/gl_kernel_procamp_2021/03_module/argsmod.ko
+make[1]: Leaving directory '/home/victor/work/buildroot-2021.02.7/output/build/linux-5.10.7'
diff --git a/03_module/console_log.txt b/03_module/console_log.txt
new file mode 100644
index 0000000..fea22b0
--- /dev/null
+++ b/03_module/console_log.txt
@@ -0,0 +1,32 @@
+Starting dropbear sshd: OK
+
+Welcome to Buildroot
+buildroot login: root
+# cd /home/user/
+# ls
+argsmod.ko
+# insmod argsmod.ko first_arg=3 second_arg=4
+argsmod: loading out-of-tree module taints kernel.
+3 + 4 = 7
+# rmmod argsmod.ko 
+3 - 4 = -1
+# insmod argsmod.ko first_arg=8 second_arg=6
+8 + 6 = 14
+# rmmod argsmod.ko 
+8 - 6 = 2
+# insmod argsmod.ko first_arg=5
+5 + 0 = 5
+# rmmod argsmod.ko 
+5 - 0 = 5
+# insmod argsmod.ko second_arg=10
+0 + 10 = 10
+# rmmod argsmod.ko 
+0 - 10 = -10
+# insmod argsmod.ko
+0 + 0 = 0
+# rmmod argsmod.ko 
+0 - 0 = 0
+# exit
+
+Welcome to Buildroot
+buildroot login: qemu-system-x86_64: terminating on signal 2
diff --git a/03_module/dmesg_log.txt b/03_module/dmesg_log.txt
new file mode 100644
index 0000000..5ebded5
--- /dev/null
+++ b/03_module/dmesg_log.txt
@@ -0,0 +1,12 @@
+# dmesg
+argsmod: loading out-of-tree module taints kernel.
+3 + 4 = 7
+3 - 4 = -1
+8 + 6 = 14
+8 - 6 = 2
+5 + 0 = 5
+5 - 0 = 5
+0 + 10 = 10
+0 - 10 = -10
+0 + 0 = 0
+0 - 0 = 0