GNUBoot
/
hardware-init-review
2
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

WIP

This commit is contained in:
Adrien Bourmault 2024-08-21 21:27:29 +02:00
parent 46e774a62c
commit 312b458ec5
Signed by: neox
GPG Key ID: 57BC26A3687116F6
6 changed files with 300 additions and 253 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
Makefile
View File

@ -1,23 +1,25 @@
.PHONY: clean distclean all bibliography .PHONY: clean distclean all force_update
all: hardware_init_review.pdf XELATEX=xelatex -shell-escape
DOC=hardware_init_review
all: $(DOC).pdf
clean: clean:
rm -rf *.log *.bak *.out *.xml *.gz *.aux *.bcf *.blg rm -rf *.log *.bak *.out *.xml *.gz *.aux *.bcf *.blg
distclean: clean distclean: clean
rm -rf *.bbl *.pdf *.toc rm -rf *.bbl *.pdf *.toc $(DOC).bibready
bibliography: hardware_init_review.bbl $(DOC).bibready:
$(XELATEX) $(DOC).tex
touch $(DOC).bibready
hardware_init_review.bbl: bibliographie.bib hardware_init_review.bcf $(DOC).bbl: $(DOC).bibready bibliographie.bib
biber hardware_init_review biber $(DOC)
hardware_init_review.bcf: $(DOC).pdf: $(DOC).bbl $(DOC).tex
xelatex hardware_init_review.tex $(XELATEX) $(DOC).tex
hardware_init_review.toc: force_update: $(DOC).toc
xelatex hardware_init_review.tex $(XELATEX) $(DOC).tex
hardware_init_review.pdf: hardware_init_review.bbl hardware_init_review.toc
xelatex hardware_init_review.tex

BIN
hardware_init_review.pdf
View File

Binary file not shown.

175
hardware_init_review.tex
View File

@ -8,9 +8,9 @@
% setup bibliography % setup bibliography
\addbibresource{bibliographie.bib} \addbibresource{bibliographie.bib}
% -------------------------------------------------------------------------------------- % ------------------------------------------------------------------------------
\begin{document}{ \begin{document}{
% -------------------------------------------------------------------------------------- % ------------------------------------------------------------------------------
\sloppy % allow flexible margins \sloppy % allow flexible margins
@ -18,22 +18,22 @@
\newpage \newpage
% -------------------------------------------------------------------------------------- % --------------------------------------------------------------------------------------
% License page % License header
% -------------------------------------------------------------------------------------- % --------------------------------------------------------------------------------------
\setcounter{page}{2} \setcounter{page}{2}
\vspace*{\fill} % fill the page so that text is at the bottom \vspace*{\fill} % fill the page so that text is at the bottom
This is Edition 0.0. \newline This is Edition 0.0. \newline
Copyright (C) 2024 Adrien 'neox' Bourmault \href{mailto:neox@gnu.org}{<neox@gnu.org>} \newline Copyright (C) 2024 Adrien 'neox' Bourmault \href{mailto:neox@gnu.org}{<neox@gnu.org>} \newline
Permission is granted to copy, distribute and/or modify this document Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 under the terms of the GNU Free Documentation License, Version 1.3
or any later version published by the Free Software Foundation; or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
A copy of the license is included in the section entitled "GNU A copy of the license is included in the section entitled "GNU
Free Documentation License". Free Documentation License".
\newpage \newpage
@ -46,44 +46,44 @@ Free Documentation License".
\addcontentsline{toc}{chapter}{Abstract} \addcontentsline{toc}{chapter}{Abstract}
The global trend is towards the scarcity of free software-compatible hardware, The global trend is towards the scarcity of free software-compatible hardware,
and soon there will be no computer that will work without software domination and soon there will be no computer that will work without software domination
by big companies, especially involving firmware like BIOSes. \\ by big companies, especially involving firmware like BIOSes. \\
A Basic Input Output System A Basic Input Output System
(BIOS) was originally a set of low-level functions contained in the read-only (BIOS) was originally a set of low-level functions contained in the read-only
memory of a computer's mainboard, enabling it to perform basic operations when memory of a computer's mainboard, enabling it to perform basic operations when
powered up. However, the definition of a BIOS has evolved to include what used powered up. However, the definition of a BIOS has evolved to include what used
to be known as Power On Self Test (POST) for the presence of peripherals, to be known as Power On Self Test (POST) for the presence of peripherals,
allocating resources for them to avoid conflicts, and then handing over to an allocating resources for them to avoid conflicts, and then handing over to an
operating system boot loader. Nowadays, the bulk of the BIOS work is the operating system boot loader. Nowadays, the bulk of the BIOS work is the
initialization and training of RAM. This means, for example, initializing the initialization and training of RAM. This means, for example, initializing the
memory controller and optimizing timing and read/write voltage for optimal memory controller and optimizing timing and read/write voltage for optimal
performance, making the code complex, as its role is to optimize several performance, making the code complex, as its role is to optimize several
parallel buses operating at high speeds and shared by many CPU cores, and make parallel buses operating at high speeds and shared by many CPU cores, and make
them act as a homogeneous whole. \\ them act as a homogeneous whole. \\
This document is the product of a project hosted by the \textit{LIP6 laboratory} This document is the product of a project hosted by the \textit{LIP6 laboratory}
and supported by the \textit{GNU Boot Project} and the \textit{Free Software and supported by the \textit{GNU Boot Project} and the \textit{Free Software
Foundation}. It delves into the importance of firmware in the hardware Foundation}. It delves into the importance of firmware in the hardware
initialization of modern computers and explores various aspects of firmware, initialization of modern computers and explores various aspects of firmware,
such as Intel Management Engine (ME), AMD Platform Security Processor (PSP), such as Intel Management Engine (ME), AMD Platform Security Processor (PSP),
Advanced Configuration and Power Interface (ACPI), and System Management Mode Advanced Configuration and Power Interface (ACPI), and System Management Mode
(SMM). Additionally, it provides an in-depth look at memory initialization and (SMM). Additionally, it provides an in-depth look at memory initialization and
training algorithms, highlighting their critical role in system stability training algorithms, highlighting their critical role in system stability
and performance. Examples of the implementation in the ASUS KGPE-D16 mainboard are and performance. Examples of the implementation in the ASUS KGPE-D16 mainboard are
presented, describing its hardware characteristics, topology, and the crucial role presented, describing its hardware characteristics, topology, and the crucial role
of firmware in its operation after the mainboard architecture is examined. of firmware in its operation after the mainboard architecture is examined.
Practical examples illustrate the impact of firmware on hardware Practical examples illustrate the impact of firmware on hardware
initialization, memory optimization, resource allocation, power management, initialization, memory optimization, resource allocation, power management,
and security. Specific algorithms used for memory training and their outcomes and security. Specific algorithms used for memory training and their outcomes
are analyzed to demonstrate the complexity and importance of firmware in are analyzed to demonstrate the complexity and importance of firmware in
achieving optimal system performance. achieving optimal system performance.
Furthermore, this document explores the relationship between firmware and Furthermore, this document explores the relationship between firmware and
hardware virtualization, discussing how modern firmware supports and enhances hardware virtualization, discussing how modern firmware supports and enhances
virtualized environments. Security considerations and future trends in virtualized environments. Security considerations and future trends in
firmware development are also addressed, emphasizing the need for continued firmware development are also addressed, emphasizing the need for continued
research and advocacy for free software-compatible hardware. research and advocacy for free software-compatible hardware.
\chapter{Introduction to firmware and BIOS evolution} \chapter{Introduction to firmware and BIOS evolution}
@ -695,11 +695,11 @@ research and advocacy for free software-compatible hardware.
physical disk, referred to here as ROM. A number of independent components, each physical disk, referred to here as ROM. A number of independent components, each
with a header added to the data, are located within the ROM. The components are with a header added to the data, are located within the ROM. The components are
nominally arranged sequentially, although they are aligned along a predefined nominally arranged sequentially, although they are aligned along a predefined
boundary \ref{fig:coreboot_diagram}). \\ boundary (fig. \ref{fig:coreboot_diagram}). \\
Each stage is compiled as a separate binary and inserted into the CBFS with Each stage is compiled as a separate binary and inserted into the CBFS with
custom compression. The \textbf{bootblock} is usually not compressed, while the custom compression. The bootblock stage is usually not compressed, while the
\textbf{ramstage} and the \textbf{payload} are compressed with LZMA. ramstage and the payload are compressed with LZMA.
Each stage loads the next stage at a given address (possibly decompressing it Each stage loads the next stage at a given address (possibly decompressing it
in the process). \\ in the process). \\
@ -713,7 +713,7 @@ research and advocacy for free software-compatible hardware.
\end{figure} \end{figure}
Some stages are relocatable and can be placed anywhere in the RAM. These stages Some stages are relocatable and can be placed anywhere in the RAM. These stages
are typically cached in the \textbf{CBMEM} for faster loading times during are typically cached in the CBMEM for faster loading times during
wake-up. The CBMEM is a specific memory area used by the wake-up. The CBMEM is a specific memory area used by the
\textit{coreboot} firmware to store important data structures and logs during the \textit{coreboot} firmware to store important data structures and logs during the
boot process. This area is typically allocated in the system's RAM and is used to boot process. This area is typically allocated in the system's RAM and is used to
@ -722,52 +722,70 @@ research and advocacy for free software-compatible hardware.
\subsection{Bootblock stage} \subsection{Bootblock stage}
The \textbf{bootblock} is the first stage executed after the CPU reset. The bootblock is the first stage executed after the CPU reset.
The beginning of this stage is written in assembly language, and its main task is The beginning of this stage is written in assembly language, and its main task is
to set everything up for a C environment. The rest, of course, is written in C. to set everything up for a C environment. The rest, of course, is written in C.
\\ This stage occupies the last 20k (fig. \ref{fig:coreboot_diagram}) of the image
and within it is a main header containing information about the ROM, including
The \textbf{bootblock} occupies the last 20k and within it is a main the size, component alignment, and the offset of the start of the first CBFS
header containing information about the ROM, including the size, component component in the ROM.
alignment, and the offset of the start of the first CBFS component in the ROM. This block is a mandatory component as it also contains the entry point of the
This block is a mandatory component of the ROM as it also contains the entry firmware. \\
point of the firmware. \\
Upon startup, this stage is responsible for the initial hardware setup, which Upon startup, this stage is responsible for the initial hardware setup, which
involves identifying and configuring the CPU. This process is particularly involves identifying and configuring the CPU. This process is particularly
significant for AMD Family 10h/15h processors, where the firmware sets up the significant for AMD Family 10h/15h processors, where the firmware sets up the
Bootstrap Processor (BSP) and executes the necessary initialization routines. Bootstrap Processor (BSP) and executes the necessary initialization routines:
Using the BSP, it enables the processor's cache, a small but fast type of memory using the BSP, it enables the processor's cache, a small but fast type of memory
that stores frequently accessed data, improving overall system speed by reducing that stores frequently accessed data, improving overall system speed by reducing
data access time. However, the cache is there used as memory since DDR DIMMs are data access time. However, the cache is there used as memory since DDR DIMMs are
not available yet. It is done by programing the \textbf{Memory Type Range not available yet. This is done by programming the Memory Type Range
Registers} (MTRRs), which define how different ranges of system memory are Registers (MTRRs), which define how different ranges of system memory are
accessed, such as whether they are cacheable or non-cacheable, used to optimize accessed such as whether they are cacheable or non-cacheable, used to optimize
memory performance on normal operation. memory performance on normal operation \cite{BKDG}.
The firmware will then set the stack pointer, allocate memory for the BSS, and The firmware will then set the stack pointer, allocate memory for the BSS, and
decompress and load the next stage. On x86 platforms, this process also includes decompress and load the next stage. On x86 platforms, this process also includes
updating the CPU microcode, initializing the timer, and transitioning from 16-bit updating the CPU microcode, initializing the timer, and transitioning from 16-bit
real mode to 32-bit protected mode. The \textbf{bootblock} is responsible for real mode to 32-bit protected mode. The bootblock is responsible for
loading the romstage, or the verstage if verified boot is enabled. loading the romstage, or the verstage if verified boot is enabled
\cite{coreboot_docs}.
\subsection{Romstage} \subsection{Romstage}
The firmware also configures the Advanced Programmable Interrupt Controller The purpose of the romstage is the early initialization of peripherals,
(APIC), which manages how the processor handles interrupts to ensure particularly system memory. The firmware also configures the Advanced
the system can respond efficiently to hardware and Programmable Interrupt Controller (APIC), responsible in handling interrupts
software events. Lastly, it sets up the routing for HyperTransport (HT) correctly across multiple CPUs, particularly in systems that use Symmetric
Multiprocessing (SMP).
In this phase, \textit{coreboot} sets up the APIC to manage interrupt routing,
which includes configuring the Local APIC on each processor and the IOAPIC, part
of the southbridge, for routing interrupts from peripherals to the appropriate
CPUs.
Lastly, it sets up the routing for HyperTransport (HT)
technology, a high-speed communication protocol used for data exchange between technology, a high-speed communication protocol used for data exchange between
the processor and the northbridge, ensuring that data flows smoothly the processor and the northbridge, ensuring that data flows smoothly
between these components. between these components. \\
Memory training and optimization are key functions of the firmware. During this Memory training and optimization are key functions of the firmware. During this
process, the firmware adjusts memory settings, such as timings, frequencies, and process, the firmware adjusts memory settings, such as timings, frequencies, and
voltages, to ensure that the installed memory modules operate efficiently and voltages, to ensure that the installed memory modules operate efficiently and
stably. This step is crucial for achieving optimal performance, especially when stably. This step is crucial for achieving optimal performance, especially when
dealing with large amounts of RAM for a large amount of CPU cores, as dealing with large amounts of RAM for a large amount of CPU cores, as
supported by the KGPE-D16. \\ supported by the KGPE-D16. We will dive into this topic later on. \\
\subsection{Ramstage} \subsection{Ramstage}
The ramstage performs the general initialization of all peripherals, including
the initialization of PCI devices, on-chip devices, the TPM (if not done by
verstage), graphics (optional), and the CPU (setting up the System Management
Mode). After this initialization, tables are written to inform the payload or
operating system about the existence and current state of the hardware. These
tables include ACPI tables (specific to x86), SMBIOS tables (specific to x86),
coreboot tables, and updates to the device tree (specific to ARM). Additionally,
the ramstage locks down the hardware and firmware by applying write protection to
boot media, locking security-related registers, and locking SMM (specific to
x86). \\
Effective resource allocation is essential for system stability, particularly in Effective resource allocation is essential for system stability, particularly in
complex configurations involving multiple CPUs and peripherals. The firmware complex configurations involving multiple CPUs and peripherals. The firmware
manages resource allocation, resolving any conflicts between hardware components manages resource allocation, resolving any conflicts between hardware components
@ -789,6 +807,16 @@ research and advocacy for free software-compatible hardware.
TODO TODO
\begin{listing}[H]
\begin{adjustwidth}{0.5cm}{0.5cm}
\inputminted{c}{listings/test.c}
\end{adjustwidth}
\caption{\textit{Example Python functions}}
\label{lst:python_code}
\end{listing}
We saw that in (lst. \ref{lst:python_code}).
\section{Advanced Configuration and Power Interface} \section{Advanced Configuration and Power Interface}
The Advanced Configuration and Power Interface (ACPI) is a critical component The Advanced Configuration and Power Interface (ACPI) is a critical component
@ -1587,3 +1615,4 @@ free software license, such as the GNU General Public License,
to permit their use in free software. to permit their use in free software.
\end{document} \end{document}

72
hardware_init_review.toc
View File

@ -1,38 +1,38 @@
\babel@toc {english}{}\relax \babel@toc {english}{}\relax
\contentsline {chapter}{Abstract}{5}{chapter*.1}% \contentsline {chapter}{Abstract}{4}{chapter*.1}%
\contentsline {chapter}{\numberline {1}Introduction to firmware and BIOS evolution}{6}{chapter.1}% \contentsline {chapter}{\numberline {1}Introduction to firmware and BIOS evolution}{5}{chapter.1}%
\contentsline {section}{\numberline {1.1}Historical context of BIOS}{6}{section.1.1}% \contentsline {section}{\numberline {1.1}Historical context of BIOS}{5}{section.1.1}%
\contentsline {subsection}{\numberline {1.1.1}Definition and origin}{6}{subsection.1.1.1}% \contentsline {subsection}{\numberline {1.1.1}Definition and origin}{5}{subsection.1.1.1}%
\contentsline {subsection}{\numberline {1.1.2}Functionalities and limitations}{7}{subsection.1.1.2}% \contentsline {subsection}{\numberline {1.1.2}Functionalities and limitations}{6}{subsection.1.1.2}%
\contentsline {section}{\numberline {1.2}Modern BIOS and UEFI}{8}{section.1.2}% \contentsline {section}{\numberline {1.2}Modern BIOS and UEFI}{7}{section.1.2}%
\contentsline {subsection}{\numberline {1.2.1}Transition from traditional BIOS to UEFI (Unified Extensible Firmware Interface)}{8}{subsection.1.2.1}% \contentsline {subsection}{\numberline {1.2.1}Transition from traditional BIOS to UEFI (Unified Extensible Firmware Interface)}{7}{subsection.1.2.1}%
\contentsline {subsection}{\numberline {1.2.2}An other way with \textit {coreboot}}{8}{subsection.1.2.2}% \contentsline {subsection}{\numberline {1.2.2}An other way with \textit {coreboot}}{7}{subsection.1.2.2}%
\contentsline {section}{\numberline {1.3}Shift in firmware responsibilities}{10}{section.1.3}% \contentsline {section}{\numberline {1.3}Shift in firmware responsibilities}{9}{section.1.3}%
\contentsline {chapter}{\numberline {2}Characteristics of ASUS KGPE-D16 mainboard}{11}{chapter.2}% \contentsline {chapter}{\numberline {2}Characteristics of ASUS KGPE-D16 mainboard}{10}{chapter.2}%
\contentsline {section}{\numberline {2.1}Overview of ASUS KGPE-D16 hardware}{12}{section.2.1}% \contentsline {section}{\numberline {2.1}Overview of ASUS KGPE-D16 hardware}{11}{section.2.1}%
\contentsline {section}{\numberline {2.2}Chipset}{13}{section.2.2}% \contentsline {section}{\numberline {2.2}Chipset}{12}{section.2.2}%
\contentsline {section}{\numberline {2.3}Processors}{15}{section.2.3}% \contentsline {section}{\numberline {2.3}Processors}{14}{section.2.3}%
\contentsline {section}{\numberline {2.4}Baseboard Management Controller}{16}{section.2.4}% \contentsline {section}{\numberline {2.4}Baseboard Management Controller}{15}{section.2.4}%
\contentsline {chapter}{\numberline {3}Key components in modern firmware [WIP]}{18}{chapter.3}% \contentsline {chapter}{\numberline {3}Key components in modern firmware [WIP]}{17}{chapter.3}%
\contentsline {section}{\numberline {3.1}General structure of coreboot}{18}{section.3.1}% \contentsline {section}{\numberline {3.1}General structure of coreboot}{17}{section.3.1}%
\contentsline {subsection}{\numberline {3.1.1}Bootblock stage}{19}{subsection.3.1.1}% \contentsline {subsection}{\numberline {3.1.1}Bootblock stage}{18}{subsection.3.1.1}%
\contentsline {subsection}{\numberline {3.1.2}Romstage}{19}{subsection.3.1.2}% \contentsline {subsection}{\numberline {3.1.2}Romstage}{18}{subsection.3.1.2}%
\contentsline {subsection}{\numberline {3.1.3}Ramstage}{20}{subsection.3.1.3}% \contentsline {subsection}{\numberline {3.1.3}Ramstage}{19}{subsection.3.1.3}%
\contentsline {subsection}{\numberline {3.1.4}Payload}{20}{subsection.3.1.4}% \contentsline {subsection}{\numberline {3.1.4}Payload}{19}{subsection.3.1.4}%
\contentsline {section}{\numberline {3.2}Advanced Configuration and Power Interface}{20}{section.3.2}% \contentsline {section}{\numberline {3.2}Advanced Configuration and Power Interface}{19}{section.3.2}%
\contentsline {section}{\numberline {3.3}System Management Mode}{21}{section.3.3}% \contentsline {section}{\numberline {3.3}System Management Mode}{20}{section.3.3}%
\contentsline {section}{\numberline {3.4}AMD Platform Security Processor and Intel Management Engine}{21}{section.3.4}% \contentsline {section}{\numberline {3.4}AMD Platform Security Processor and Intel Management Engine}{21}{section.3.4}%
\contentsline {chapter}{\numberline {4}Memory initialization and training algorithms [WIP]}{23}{chapter.4}% \contentsline {chapter}{\numberline {4}Memory initialization and training algorithms [WIP]}{22}{chapter.4}%
\contentsline {section}{\numberline {4.1}Importance of memory initialization}{23}{section.4.1}% \contentsline {section}{\numberline {4.1}Importance of memory initialization}{22}{section.4.1}%
\contentsline {section}{\numberline {4.2}Memory training algorithms}{23}{section.4.2}% \contentsline {section}{\numberline {4.2}Memory training algorithms}{22}{section.4.2}%
\contentsline {section}{\numberline {4.3}Practical examples}{24}{section.4.3}% \contentsline {section}{\numberline {4.3}Practical examples}{23}{section.4.3}%
\contentsline {chapter}{\numberline {5}Firmware and hardware virtualization [WIP]}{25}{chapter.5}% \contentsline {chapter}{\numberline {5}Firmware and hardware virtualization [WIP]}{24}{chapter.5}%
\contentsline {section}{\numberline {5.1}Introduction to hardware virtualization}{25}{section.5.1}% \contentsline {section}{\numberline {5.1}Introduction to hardware virtualization}{24}{section.5.1}%
\contentsline {section}{\numberline {5.2}Role of BIOS/UEFI in virtualization}{25}{section.5.2}% \contentsline {section}{\numberline {5.2}Role of BIOS/UEFI in virtualization}{24}{section.5.2}%
\contentsline {section}{\numberline {5.3}Security and freedom considerations}{25}{section.5.3}% \contentsline {section}{\numberline {5.3}Security and freedom considerations}{24}{section.5.3}%
\contentsline {section}{\numberline {5.4}Future trends in firmware and virtualization}{25}{section.5.4}% \contentsline {section}{\numberline {5.4}Future trends in firmware and virtualization}{24}{section.5.4}%
\contentsline {chapter}{Conclusion}{26}{chapter*.2}% \contentsline {chapter}{Conclusion}{25}{chapter*.2}%
\contentsline {section}{\numberline {5.5}Summary of key points}{26}{section.5.5}% \contentsline {section}{\numberline {5.5}Summary of key points}{25}{section.5.5}%
\contentsline {section}{\numberline {5.6}Call for action}{26}{section.5.6}% \contentsline {section}{\numberline {5.6}Call for action}{25}{section.5.6}%
\contentsline {chapter}{Bibliography}{27}{section.5.6}% \contentsline {chapter}{Bibliography}{26}{section.5.6}%
\contentsline {chapter}{GNU Free Documentation License}{32}{chapter*.4}% \contentsline {chapter}{GNU Free Documentation License}{31}{chapter*.4}%

4
listings/test.c Normal file
View File

@ -0,0 +1,4 @@
void main(int a, int b)
{
return 0;
}

14
packages.tex
View File

@ -13,9 +13,11 @@
\usepackage[T1]{fontenc} \usepackage[T1]{fontenc}
\usepackage[english]{babel} \usepackage[english]{babel}
\usepackage{graphicx} \usepackage{graphicx}
\usepackage{listings} \usepackage{listing}
\usepackage{minted}
\usepackage{xcolor} \usepackage{xcolor}
\usepackage{chngcntr} \usepackage{chngcntr}
\usepackage{changepage}
\usepackage[a4paper, portrait, margin=1.45cm]{geometry} \usepackage[a4paper, portrait, margin=1.45cm]{geometry}
\title{Titre du mémoire} \title{Titre du mémoire}
\author{Nom et prénom de l'auteur} \author{Nom et prénom de l'auteur}
@ -46,3 +48,13 @@
\renewcommand{\familydefault}{\sfdefault} \renewcommand{\familydefault}{\sfdefault}
\setlength\parindent{0pt} \setlength\parindent{0pt}
\usemintedstyle{solarized-light}
\definecolor{bg}{HTML}{FAF9F6}
\definecolor{linenumcolor}{rgb}{0.6, 0.6, 0.6} % Light gray color
%\renewcommand{\theFancyVerbLine}{\textcolor{linenumcolor}{\arabic{FancyVerbLine}}}
\setminted{
linenos,
numbersep=5pt,
bgcolor=bg
}