How to apply patch linux

Applying Patches To The Linux Kernel¶

This document is obsolete. In most cases, rather than using patch manually, you’ll almost certainly want to look at using Git instead.

A frequently asked question on the Linux Kernel Mailing List is how to apply a patch to the kernel or, more specifically, what base kernel a patch for one of the many trees/branches should be applied to. Hopefully this document will explain this to you.

In addition to explaining how to apply and revert patches, a brief description of the different kernel trees (and examples of how to apply their specific patches) is also provided.

What is a patch?В¶

A patch is a small text document containing a delta of changes between two different versions of a source tree. Patches are created with the diff program.

To correctly apply a patch you need to know what base it was generated from and what new version the patch will change the source tree into. These should both be present in the patch file metadata or be possible to deduce from the filename.

How do I apply or revert a patch?В¶

You apply a patch with the patch program. The patch program reads a diff (or patch) file and makes the changes to the source tree described in it.

Patches for the Linux kernel are generated relative to the parent directory holding the kernel source dir.

This means that paths to files inside the patch file contain the name of the kernel source directories it was generated against (or some other directory names like “a/” and “b/”).

You can revert (undo) it like this:

This (as usual with Linux and other UNIX like operating systems) can be done in several different ways.

In all the examples below I feed the file (in uncompressed form) to patch via stdin using the following syntax:

If you just want to be able to follow the examples below and don’t want to know of more than one way to use patch, then you can stop reading this section here.

If your patch file is compressed with gzip or xz and you don’t want to uncompress it before applying it, then you can feed it to patch like this instead:

If you wish to uncompress the patch file by hand first before applying it (what I assume you’ve done in the examples below), then you simply run gunzip or xz on the file – like this:

Common errors when patching¶

When patch applies a patch file it attempts to verify the sanity of the file in different ways.

Checking that the file looks like a valid patch file and checking the code around the bits being modified matches the context provided in the patch are just two of the basic sanity checks patch does.

If patch encounters something that doesn’t look quite right it has two options. It can either refuse to apply the changes and abort or it can try to find a way to make the patch apply with a few minor changes.

One example of something that’s not ‘quite right’ that patch will attempt to fix up is if all the context matches, the lines being changed match, but the line numbers are different. This can happen, for example, if the patch makes a change in the middle of the file but for some reasons a few lines have been added or removed near the beginning of the file. In that case everything looks good it has just moved up or down a bit, and patch will usually adjust the line numbers and apply the patch.

Whenever patch applies a patch that it had to modify a bit to make it fit it’ll tell you about it by saying the patch applied with fuzz. You should be wary of such changes since even though patch probably got it right it doesn’t /always/ get it right, and the result will sometimes be wrong.

If you don’t have any third-party patches applied to your kernel source, but only patches from kernel.org and you apply the patches in the correct order, and have made no modifications yourself to the source files, then you should never see a fuzz or reject message from patch. If you do see such messages anyway, then there’s a high risk that either your local source tree or the patch file is corrupted in some way. In that case you should probably try re-downloading the patch and if things are still not OK then you’d be advised to start with a fresh tree downloaded in full from kernel.org.

Let’s look a bit more at some of the messages patch can produce.

If you get Hunk #2 succeeded at 1887 with fuzz 2 (offset 7 lines). or a message similar to that, then it means that patch had to adjust the location of the change (in this example it needed to move 7 lines from where it expected to make the change to make it fit).

The resulting file may or may not be OK, depending on the reason the file was different than expected.

This often happens if you try to apply a patch that was generated against a different kernel version than the one you are trying to patch.

This can also happen if the creator of the patch reversed the source and destination directories when creating the patch, and in that case reverting the patch will in fact apply it.

A message similar to patch: **** unexpected end of file in patch or patch unexpectedly ends in middle of line means that patch could make no sense of the file you fed to it. Either your download is broken, you tried to feed patch a compressed patch file without uncompressing it first, or the patch file that you are using has been mangled by a mail client or mail transfer agent along the way somewhere, e.g., by splitting a long line into two lines. Often these warnings can easily be fixed by joining (concatenating) the two lines that had been split.

As I already mentioned above, these errors should never happen if you apply a patch from kernel.org to the correct version of an unmodified source tree. So if you get these errors with kernel.org patches then you should probably assume that either your patch file or your tree is broken and I’d advise you to start over with a fresh download of a full kernel tree and the patch you wish to apply.

Yes there are alternatives.

You can use the interdiff program (http://cyberelk.net/tim/patchutils/) to generate a patch representing the differences between two patches and then apply the result.

Here’s how you’d go from 4.7.2 to 4.7.3 in a single step:

Although interdiff may save you a step or two you are generally advised to do the additional steps since interdiff can get things wrong in some cases.

Other nice tools are diffstat, which shows a summary of changes made by a patch; lsdiff, which displays a short listing of affected files in a patch file, along with (optionally) the line numbers of the start of each patch; and grepdiff, which displays a list of the files modified by a patch where the patch contains a given regular expression.

Where can I download the patches?В¶

The patches are available at http://kernel.org/ Most recent patches are linked from the front page, but they also have specific homes.

The 4.x.y (-stable) and 4.x patches live at

The 4.x kernels¶

These are the base stable releases released by Linus. The highest numbered release is the most recent.

To apply a patch moving from 4.6 to 4.7, you’d do the following (note that such patches do NOT apply on top of 4.x.y kernels but on top of the base 4.x kernel – if you need to move from 4.x.y to 4.x+1 you need to first revert the 4.x.y patch).

Here are some examples:

The 4.x.y kernels¶

This is the recommended branch for users who want the most recent stable kernel and are not interested in helping test development/experimental versions.

If no 4.x.y kernel is available, then the highest numbered 4.x kernel is the current stable kernel.

These patches are not incremental, meaning that for example the 4.7.3 patch does not apply on top of the 4.7.2 kernel source, but rather on top of the base 4.7 kernel source.

So, in order to apply the 4.7.3 patch to your existing 4.7.2 kernel source you have to first back out the 4.7.2 patch (so you are left with a base 4.7 kernel source) and then apply the new 4.7.3 patch.

Here’s a small example:

These are release-candidate kernels. These are development kernels released by Linus whenever he deems the current git (the kernel’s source management tool) tree to be in a reasonably sane state adequate for testing.

These kernels are not stable and you should expect occasional breakage if you intend to run them. This is however the most stable of the main development branches and is also what will eventually turn into the next stable kernel, so it is important that it be tested by as many people as possible.

So, 4.8-rc5 means that this is the fifth release candidate for the 4.8 kernel and the patch should be applied on top of the 4.7 kernel source.

Here are 3 examples of how to apply these patches:

This concludes this list of explanations of the various kernel trees. I hope you are now clear on how to apply the various patches and help testing the kernel.

Thank you’s to Randy Dunlap, Rolf Eike Beer, Linus Torvalds, Bodo Eggert, Johannes Stezenbach, Grant Coady, Pavel Machek and others that I may have forgotten for their reviews and contributions to this document.

Applying Patches To The Linux Kernel¶

Jesper Juhl, August 2005

This document is obsolete. In most cases, rather than using patch manually, you’ll almost certainly want to look at using Git instead.

A frequently asked question on the Linux Kernel Mailing List is how to apply a patch to the kernel or, more specifically, what base kernel a patch for one of the many trees/branches should be applied to. Hopefully this document will explain this to you.

In addition to explaining how to apply and revert patches, a brief description of the different kernel trees (and examples of how to apply their specific patches) is also provided.

What is a patch?В¶

A patch is a small text document containing a delta of changes between two different versions of a source tree. Patches are created with the diff program.

To correctly apply a patch you need to know what base it was generated from and what new version the patch will change the source tree into. These should both be present in the patch file metadata or be possible to deduce from the filename.

How do I apply or revert a patch?В¶

You apply a patch with the patch program. The patch program reads a diff (or patch) file and makes the changes to the source tree described in it.

Patches for the Linux kernel are generated relative to the parent directory holding the kernel source dir.

This means that paths to files inside the patch file contain the name of the kernel source directories it was generated against (or some other directory names like “a/” and “b/”).

You can revert (undo) it like this:

This (as usual with Linux and other UNIX like operating systems) can be done in several different ways.

In all the examples below I feed the file (in uncompressed form) to patch via stdin using the following syntax:

If you just want to be able to follow the examples below and don’t want to know of more than one way to use patch, then you can stop reading this section here.

If your patch file is compressed with gzip or xz and you don’t want to uncompress it before applying it, then you can feed it to patch like this instead:

If you wish to uncompress the patch file by hand first before applying it (what I assume you’ve done in the examples below), then you simply run gunzip or xz on the file – like this:

Common errors when patching¶

When patch applies a patch file it attempts to verify the sanity of the file in different ways.

Checking that the file looks like a valid patch file and checking the code around the bits being modified matches the context provided in the patch are just two of the basic sanity checks patch does.

If patch encounters something that doesn’t look quite right it has two options. It can either refuse to apply the changes and abort or it can try to find a way to make the patch apply with a few minor changes.

One example of something that’s not ‘quite right’ that patch will attempt to fix up is if all the context matches, the lines being changed match, but the line numbers are different. This can happen, for example, if the patch makes a change in the middle of the file but for some reasons a few lines have been added or removed near the beginning of the file. In that case everything looks good it has just moved up or down a bit, and patch will usually adjust the line numbers and apply the patch.

Whenever patch applies a patch that it had to modify a bit to make it fit it’ll tell you about it by saying the patch applied with fuzz. You should be wary of such changes since even though patch probably got it right it doesn’t /always/ get it right, and the result will sometimes be wrong.

If you don’t have any third-party patches applied to your kernel source, but only patches from kernel.org and you apply the patches in the correct order, and have made no modifications yourself to the source files, then you should never see a fuzz or reject message from patch. If you do see such messages anyway, then there’s a high risk that either your local source tree or the patch file is corrupted in some way. In that case you should probably try re-downloading the patch and if things are still not OK then you’d be advised to start with a fresh tree downloaded in full from kernel.org.

Let’s look a bit more at some of the messages patch can produce.

If you get Hunk #2 succeeded at 1887 with fuzz 2 (offset 7 lines). or a message similar to that, then it means that patch had to adjust the location of the change (in this example it needed to move 7 lines from where it expected to make the change to make it fit).

The resulting file may or may not be OK, depending on the reason the file was different than expected.

This often happens if you try to apply a patch that was generated against a different kernel version than the one you are trying to patch.

This can also happen if the creator of the patch reversed the source and destination directories when creating the patch, and in that case reverting the patch will in fact apply it.

A message similar to patch: **** unexpected end of file in patch or patch unexpectedly ends in middle of line means that patch could make no sense of the file you fed to it. Either your download is broken, you tried to feed patch a compressed patch file without uncompressing it first, or the patch file that you are using has been mangled by a mail client or mail transfer agent along the way somewhere, e.g., by splitting a long line into two lines. Often these warnings can easily be fixed by joining (concatenating) the two lines that had been split.

As I already mentioned above, these errors should never happen if you apply a patch from kernel.org to the correct version of an unmodified source tree. So if you get these errors with kernel.org patches then you should probably assume that either your patch file or your tree is broken and I’d advise you to start over with a fresh download of a full kernel tree and the patch you wish to apply.

Yes there are alternatives.

You can use the interdiff program (http://cyberelk.net/tim/patchutils/) to generate a patch representing the differences between two patches and then apply the result.

Here’s how you’d go from 5.7.2 to 5.7.3 in a single step:

Although interdiff may save you a step or two you are generally advised to do the additional steps since interdiff can get things wrong in some cases.

Other nice tools are diffstat, which shows a summary of changes made by a patch; lsdiff, which displays a short listing of affected files in a patch file, along with (optionally) the line numbers of the start of each patch; and grepdiff, which displays a list of the files modified by a patch where the patch contains a given regular expression.

Where can I download the patches?В¶

The patches are available at https://kernel.org/ Most recent patches are linked from the front page, but they also have specific homes.

The 5.x.y (-stable) and 5.x patches live at

The 5.x.y incremental patches live at

The 5.x kernels¶

These are the base stable releases released by Linus. The highest numbered release is the most recent.

To apply a patch moving from 5.6 to 5.7, you’d do the following (note that such patches do NOT apply on top of 5.x.y kernels but on top of the base 5.x kernel – if you need to move from 5.x.y to 5.x+1 you need to first revert the 5.x.y patch).

Here are some examples:

The 5.x.y kernels¶

This is the recommended branch for users who want the most recent stable kernel and are not interested in helping test development/experimental versions.

If no 5.x.y kernel is available, then the highest numbered 5.x kernel is the current stable kernel.

Normal patches¶

These patches are not incremental, meaning that for example the 5.7.3 patch does not apply on top of the 5.7.2 kernel source, but rather on top of the base 5.7 kernel source.

So, in order to apply the 5.7.3 patch to your existing 5.7.2 kernel source you have to first back out the 5.7.2 patch (so you are left with a base 5.7 kernel source) and then apply the new 5.7.3 patch.

Here’s a small example:

Incremental patches¶

Incremental patches are different: instead of being applied on top of base 5.x kernel, they are applied on top of previous stable kernel (5.x.y-1).

Here’s the example to apply these:

These are release-candidate kernels. These are development kernels released by Linus whenever he deems the current git (the kernel’s source management tool) tree to be in a reasonably sane state adequate for testing.

These kernels are not stable and you should expect occasional breakage if you intend to run them. This is however the most stable of the main development branches and is also what will eventually turn into the next stable kernel, so it is important that it be tested by as many people as possible.

So, 5.8-rc5 means that this is the fifth release candidate for the 5.8 kernel and the patch should be applied on top of the 5.7 kernel source.

Here are 3 examples of how to apply these patches:

This concludes this list of explanations of the various kernel trees. I hope you are now clear on how to apply the various patches and help testing the kernel.

Thank you’s to Randy Dunlap, Rolf Eike Beer, Linus Torvalds, Bodo Eggert, Johannes Stezenbach, Grant Coady, Pavel Machek and others that I may have forgotten for their reviews and contributions to this document.

© Copyright The kernel development community.

Applying Patches To The Linux Kernel¶

This document is obsolete. In most cases, rather than using patch manually, you’ll almost certainly want to look at using Git instead.

A frequently asked question on the Linux Kernel Mailing List is how to apply a patch to the kernel or, more specifically, what base kernel a patch for one of the many trees/branches should be applied to. Hopefully this document will explain this to you.

In addition to explaining how to apply and revert patches, a brief description of the different kernel trees (and examples of how to apply their specific patches) is also provided.

What is a patch?В¶

A patch is a small text document containing a delta of changes between two different versions of a source tree. Patches are created with the diff program.

To correctly apply a patch you need to know what base it was generated from and what new version the patch will change the source tree into. These should both be present in the patch file metadata or be possible to deduce from the filename.

How do I apply or revert a patch?В¶

You apply a patch with the patch program. The patch program reads a diff (or patch) file and makes the changes to the source tree described in it.

Patches for the Linux kernel are generated relative to the parent directory holding the kernel source dir.

This means that paths to files inside the patch file contain the name of the kernel source directories it was generated against (or some other directory names like “a/” and “b/”).

You can revert (undo) it like this:

This (as usual with Linux and other UNIX like operating systems) can be done in several different ways.

In all the examples below I feed the file (in uncompressed form) to patch via stdin using the following syntax:

If you just want to be able to follow the examples below and don’t want to know of more than one way to use patch, then you can stop reading this section here.

If your patch file is compressed with gzip or xz and you don’t want to uncompress it before applying it, then you can feed it to patch like this instead:

If you wish to uncompress the patch file by hand first before applying it (what I assume you’ve done in the examples below), then you simply run gunzip or xz on the file – like this:

Common errors when patching¶

When patch applies a patch file it attempts to verify the sanity of the file in different ways.

Checking that the file looks like a valid patch file and checking the code around the bits being modified matches the context provided in the patch are just two of the basic sanity checks patch does.

If patch encounters something that doesn’t look quite right it has two options. It can either refuse to apply the changes and abort or it can try to find a way to make the patch apply with a few minor changes.

One example of something that’s not ‘quite right’ that patch will attempt to fix up is if all the context matches, the lines being changed match, but the line numbers are different. This can happen, for example, if the patch makes a change in the middle of the file but for some reasons a few lines have been added or removed near the beginning of the file. In that case everything looks good it has just moved up or down a bit, and patch will usually adjust the line numbers and apply the patch.

Whenever patch applies a patch that it had to modify a bit to make it fit it’ll tell you about it by saying the patch applied with fuzz. You should be wary of such changes since even though patch probably got it right it doesn’t /always/ get it right, and the result will sometimes be wrong.

If you don’t have any third-party patches applied to your kernel source, but only patches from kernel.org and you apply the patches in the correct order, and have made no modifications yourself to the source files, then you should never see a fuzz or reject message from patch. If you do see such messages anyway, then there’s a high risk that either your local source tree or the patch file is corrupted in some way. In that case you should probably try re-downloading the patch and if things are still not OK then you’d be advised to start with a fresh tree downloaded in full from kernel.org.

Let’s look a bit more at some of the messages patch can produce.

If you get Hunk #2 succeeded at 1887 with fuzz 2 (offset 7 lines). or a message similar to that, then it means that patch had to adjust the location of the change (in this example it needed to move 7 lines from where it expected to make the change to make it fit).

The resulting file may or may not be OK, depending on the reason the file was different than expected.

This often happens if you try to apply a patch that was generated against a different kernel version than the one you are trying to patch.

This can also happen if the creator of the patch reversed the source and destination directories when creating the patch, and in that case reverting the patch will in fact apply it.

A message similar to patch: **** unexpected end of file in patch or patch unexpectedly ends in middle of line means that patch could make no sense of the file you fed to it. Either your download is broken, you tried to feed patch a compressed patch file without uncompressing it first, or the patch file that you are using has been mangled by a mail client or mail transfer agent along the way somewhere, e.g., by splitting a long line into two lines. Often these warnings can easily be fixed by joining (concatenating) the two lines that had been split.

As I already mentioned above, these errors should never happen if you apply a patch from kernel.org to the correct version of an unmodified source tree. So if you get these errors with kernel.org patches then you should probably assume that either your patch file or your tree is broken and I’d advise you to start over with a fresh download of a full kernel tree and the patch you wish to apply.

Yes there are alternatives.

You can use the interdiff program (http://cyberelk.net/tim/patchutils/) to generate a patch representing the differences between two patches and then apply the result.

Here’s how you’d go from 4.7.2 to 4.7.3 in a single step:

Although interdiff may save you a step or two you are generally advised to do the additional steps since interdiff can get things wrong in some cases.

Other nice tools are diffstat, which shows a summary of changes made by a patch; lsdiff, which displays a short listing of affected files in a patch file, along with (optionally) the line numbers of the start of each patch; and grepdiff, which displays a list of the files modified by a patch where the patch contains a given regular expression.

Where can I download the patches?В¶

The patches are available at http://kernel.org/ Most recent patches are linked from the front page, but they also have specific homes.

The 4.x.y (-stable) and 4.x patches live at

The 4.x kernels¶

These are the base stable releases released by Linus. The highest numbered release is the most recent.

To apply a patch moving from 4.6 to 4.7, you’d do the following (note that such patches do NOT apply on top of 4.x.y kernels but on top of the base 4.x kernel – if you need to move from 4.x.y to 4.x+1 you need to first revert the 4.x.y patch).

Here are some examples:

The 4.x.y kernels¶

This is the recommended branch for users who want the most recent stable kernel and are not interested in helping test development/experimental versions.

If no 4.x.y kernel is available, then the highest numbered 4.x kernel is the current stable kernel.

These patches are not incremental, meaning that for example the 4.7.3 patch does not apply on top of the 4.7.2 kernel source, but rather on top of the base 4.7 kernel source.

So, in order to apply the 4.7.3 patch to your existing 4.7.2 kernel source you have to first back out the 4.7.2 patch (so you are left with a base 4.7 kernel source) and then apply the new 4.7.3 patch.

Here’s a small example:

These are release-candidate kernels. These are development kernels released by Linus whenever he deems the current git (the kernel’s source management tool) tree to be in a reasonably sane state adequate for testing.

These kernels are not stable and you should expect occasional breakage if you intend to run them. This is however the most stable of the main development branches and is also what will eventually turn into the next stable kernel, so it is important that it be tested by as many people as possible.

So, 4.8-rc5 means that this is the fifth release candidate for the 4.8 kernel and the patch should be applied on top of the 4.7 kernel source.

Here are 3 examples of how to apply these patches:

These are daily snapshots of Linus’ kernel tree (managed in a git repository, hence the name).

-git patches are not incremental and apply either to a base 4.x kernel or a base 4.x-rc kernel – you can see which from their name. A patch named 4.7-git1 applies to the 4.7 kernel source and a patch named 4.8-rc3-git2 applies to the source of the 4.8-rc3 kernel.

Here are some examples of how to apply these patches:

This concludes this list of explanations of the various kernel trees. I hope you are now clear on how to apply the various patches and help testing the kernel.

Thank you’s to Randy Dunlap, Rolf Eike Beer, Linus Torvalds, Bodo Eggert, Johannes Stezenbach, Grant Coady, Pavel Machek and others that I may have forgotten for their reviews and contributions to this document.

© Copyright 2016, The kernel development community.

Applying Patches To The Linux Kernel¶

This document is obsolete. In most cases, rather than using patch manually, you’ll almost certainly want to look at using Git instead.

A frequently asked question on the Linux Kernel Mailing List is how to apply a patch to the kernel or, more specifically, what base kernel a patch for one of the many trees/branches should be applied to. Hopefully this document will explain this to you.

In addition to explaining how to apply and revert patches, a brief description of the different kernel trees (and examples of how to apply their specific patches) is also provided.

What is a patch?В¶

A patch is a small text document containing a delta of changes between two different versions of a source tree. Patches are created with the diff program.

To correctly apply a patch you need to know what base it was generated from and what new version the patch will change the source tree into. These should both be present in the patch file metadata or be possible to deduce from the filename.

How do I apply or revert a patch?В¶

You apply a patch with the patch program. The patch program reads a diff (or patch) file and makes the changes to the source tree described in it.

Patches for the Linux kernel are generated relative to the parent directory holding the kernel source dir.

This means that paths to files inside the patch file contain the name of the kernel source directories it was generated against (or some other directory names like “a/” and “b/”).

You can revert (undo) it like this:

This (as usual with Linux and other UNIX like operating systems) can be done in several different ways.

In all the examples below I feed the file (in uncompressed form) to patch via stdin using the following syntax:

If you just want to be able to follow the examples below and don’t want to know of more than one way to use patch, then you can stop reading this section here.

If your patch file is compressed with gzip or xz and you don’t want to uncompress it before applying it, then you can feed it to patch like this instead:

If you wish to uncompress the patch file by hand first before applying it (what I assume you’ve done in the examples below), then you simply run gunzip or xz on the file – like this:

Common errors when patching¶

When patch applies a patch file it attempts to verify the sanity of the file in different ways.

Checking that the file looks like a valid patch file and checking the code around the bits being modified matches the context provided in the patch are just two of the basic sanity checks patch does.

If patch encounters something that doesn’t look quite right it has two options. It can either refuse to apply the changes and abort or it can try to find a way to make the patch apply with a few minor changes.

One example of something that’s not ‘quite right’ that patch will attempt to fix up is if all the context matches, the lines being changed match, but the line numbers are different. This can happen, for example, if the patch makes a change in the middle of the file but for some reasons a few lines have been added or removed near the beginning of the file. In that case everything looks good it has just moved up or down a bit, and patch will usually adjust the line numbers and apply the patch.

Whenever patch applies a patch that it had to modify a bit to make it fit it’ll tell you about it by saying the patch applied with fuzz. You should be wary of such changes since even though patch probably got it right it doesn’t /always/ get it right, and the result will sometimes be wrong.

If you don’t have any third-party patches applied to your kernel source, but only patches from kernel.org and you apply the patches in the correct order, and have made no modifications yourself to the source files, then you should never see a fuzz or reject message from patch. If you do see such messages anyway, then there’s a high risk that either your local source tree or the patch file is corrupted in some way. In that case you should probably try re-downloading the patch and if things are still not OK then you’d be advised to start with a fresh tree downloaded in full from kernel.org.

Let’s look a bit more at some of the messages patch can produce.

If you get Hunk #2 succeeded at 1887 with fuzz 2 (offset 7 lines). or a message similar to that, then it means that patch had to adjust the location of the change (in this example it needed to move 7 lines from where it expected to make the change to make it fit).

The resulting file may or may not be OK, depending on the reason the file was different than expected.

This often happens if you try to apply a patch that was generated against a different kernel version than the one you are trying to patch.

This can also happen if the creator of the patch reversed the source and destination directories when creating the patch, and in that case reverting the patch will in fact apply it.

A message similar to patch: **** unexpected end of file in patch or patch unexpectedly ends in middle of line means that patch could make no sense of the file you fed to it. Either your download is broken, you tried to feed patch a compressed patch file without uncompressing it first, or the patch file that you are using has been mangled by a mail client or mail transfer agent along the way somewhere, e.g., by splitting a long line into two lines. Often these warnings can easily be fixed by joining (concatenating) the two lines that had been split.

As I already mentioned above, these errors should never happen if you apply a patch from kernel.org to the correct version of an unmodified source tree. So if you get these errors with kernel.org patches then you should probably assume that either your patch file or your tree is broken and I’d advise you to start over with a fresh download of a full kernel tree and the patch you wish to apply.

Yes there are alternatives.

You can use the interdiff program (http://cyberelk.net/tim/patchutils/) to generate a patch representing the differences between two patches and then apply the result.

Here’s how you’d go from 4.7.2 to 4.7.3 in a single step:

Although interdiff may save you a step or two you are generally advised to do the additional steps since interdiff can get things wrong in some cases.

Other nice tools are diffstat, which shows a summary of changes made by a patch; lsdiff, which displays a short listing of affected files in a patch file, along with (optionally) the line numbers of the start of each patch; and grepdiff, which displays a list of the files modified by a patch where the patch contains a given regular expression.

Where can I download the patches?В¶

The patches are available at http://kernel.org/ Most recent patches are linked from the front page, but they also have specific homes.

The 4.x.y (-stable) and 4.x patches live at

The 4.x kernels¶

These are the base stable releases released by Linus. The highest numbered release is the most recent.

To apply a patch moving from 4.6 to 4.7, you’d do the following (note that such patches do NOT apply on top of 4.x.y kernels but on top of the base 4.x kernel – if you need to move from 4.x.y to 4.x+1 you need to first revert the 4.x.y patch).

Here are some examples:

The 4.x.y kernels¶

This is the recommended branch for users who want the most recent stable kernel and are not interested in helping test development/experimental versions.

If no 4.x.y kernel is available, then the highest numbered 4.x kernel is the current stable kernel.

These patches are not incremental, meaning that for example the 4.7.3 patch does not apply on top of the 4.7.2 kernel source, but rather on top of the base 4.7 kernel source.

So, in order to apply the 4.7.3 patch to your existing 4.7.2 kernel source you have to first back out the 4.7.2 patch (so you are left with a base 4.7 kernel source) and then apply the new 4.7.3 patch.

Here’s a small example:

These are release-candidate kernels. These are development kernels released by Linus whenever he deems the current git (the kernel’s source management tool) tree to be in a reasonably sane state adequate for testing.

These kernels are not stable and you should expect occasional breakage if you intend to run them. This is however the most stable of the main development branches and is also what will eventually turn into the next stable kernel, so it is important that it be tested by as many people as possible.

So, 4.8-rc5 means that this is the fifth release candidate for the 4.8 kernel and the patch should be applied on top of the 4.7 kernel source.

Here are 3 examples of how to apply these patches:

This concludes this list of explanations of the various kernel trees. I hope you are now clear on how to apply the various patches and help testing the kernel.

Thank you’s to Randy Dunlap, Rolf Eike Beer, Linus Torvalds, Bodo Eggert, Johannes Stezenbach, Grant Coady, Pavel Machek and others that I may have forgotten for their reviews and contributions to this document.

Applying Patches To The Linux Kernel¶

This document is obsolete. In most cases, rather than using patch manually, you’ll almost certainly want to look at using Git instead.

A frequently asked question on the Linux Kernel Mailing List is how to apply a patch to the kernel or, more specifically, what base kernel a patch for one of the many trees/branches should be applied to. Hopefully this document will explain this to you.

In addition to explaining how to apply and revert patches, a brief description of the different kernel trees (and examples of how to apply their specific patches) is also provided.

What is a patch?В¶

A patch is a small text document containing a delta of changes between two different versions of a source tree. Patches are created with the diff program.

To correctly apply a patch you need to know what base it was generated from and what new version the patch will change the source tree into. These should both be present in the patch file metadata or be possible to deduce from the filename.

How do I apply or revert a patch?В¶

You apply a patch with the patch program. The patch program reads a diff (or patch) file and makes the changes to the source tree described in it.

Patches for the Linux kernel are generated relative to the parent directory holding the kernel source dir.

This means that paths to files inside the patch file contain the name of the kernel source directories it was generated against (or some other directory names like “a/” and “b/”).

You can revert (undo) it like this:

This (as usual with Linux and other UNIX like operating systems) can be done in several different ways.

In all the examples below I feed the file (in uncompressed form) to patch via stdin using the following syntax:

If you just want to be able to follow the examples below and don’t want to know of more than one way to use patch, then you can stop reading this section here.

If your patch file is compressed with gzip or xz and you don’t want to uncompress it before applying it, then you can feed it to patch like this instead:

If you wish to uncompress the patch file by hand first before applying it (what I assume you’ve done in the examples below), then you simply run gunzip or xz on the file – like this:

Common errors when patching¶

When patch applies a patch file it attempts to verify the sanity of the file in different ways.

Checking that the file looks like a valid patch file and checking the code around the bits being modified matches the context provided in the patch are just two of the basic sanity checks patch does.

If patch encounters something that doesn’t look quite right it has two options. It can either refuse to apply the changes and abort or it can try to find a way to make the patch apply with a few minor changes.

One example of something that’s not ‘quite right’ that patch will attempt to fix up is if all the context matches, the lines being changed match, but the line numbers are different. This can happen, for example, if the patch makes a change in the middle of the file but for some reasons a few lines have been added or removed near the beginning of the file. In that case everything looks good it has just moved up or down a bit, and patch will usually adjust the line numbers and apply the patch.

Whenever patch applies a patch that it had to modify a bit to make it fit it’ll tell you about it by saying the patch applied with fuzz. You should be wary of such changes since even though patch probably got it right it doesn’t /always/ get it right, and the result will sometimes be wrong.

If you don’t have any third-party patches applied to your kernel source, but only patches from kernel.org and you apply the patches in the correct order, and have made no modifications yourself to the source files, then you should never see a fuzz or reject message from patch. If you do see such messages anyway, then there’s a high risk that either your local source tree or the patch file is corrupted in some way. In that case you should probably try re-downloading the patch and if things are still not OK then you’d be advised to start with a fresh tree downloaded in full from kernel.org.

Let’s look a bit more at some of the messages patch can produce.

If you get Hunk #2 succeeded at 1887 with fuzz 2 (offset 7 lines). or a message similar to that, then it means that patch had to adjust the location of the change (in this example it needed to move 7 lines from where it expected to make the change to make it fit).

The resulting file may or may not be OK, depending on the reason the file was different than expected.

This often happens if you try to apply a patch that was generated against a different kernel version than the one you are trying to patch.

This can also happen if the creator of the patch reversed the source and destination directories when creating the patch, and in that case reverting the patch will in fact apply it.

A message similar to patch: **** unexpected end of file in patch or patch unexpectedly ends in middle of line means that patch could make no sense of the file you fed to it. Either your download is broken, you tried to feed patch a compressed patch file without uncompressing it first, or the patch file that you are using has been mangled by a mail client or mail transfer agent along the way somewhere, e.g., by splitting a long line into two lines. Often these warnings can easily be fixed by joining (concatenating) the two lines that had been split.

As I already mentioned above, these errors should never happen if you apply a patch from kernel.org to the correct version of an unmodified source tree. So if you get these errors with kernel.org patches then you should probably assume that either your patch file or your tree is broken and I’d advise you to start over with a fresh download of a full kernel tree and the patch you wish to apply.

Yes there are alternatives.

You can use the interdiff program (http://cyberelk.net/tim/patchutils/) to generate a patch representing the differences between two patches and then apply the result.

Here’s how you’d go from 4.7.2 to 4.7.3 in a single step:

Although interdiff may save you a step or two you are generally advised to do the additional steps since interdiff can get things wrong in some cases.

Other nice tools are diffstat, which shows a summary of changes made by a patch; lsdiff, which displays a short listing of affected files in a patch file, along with (optionally) the line numbers of the start of each patch; and grepdiff, which displays a list of the files modified by a patch where the patch contains a given regular expression.

Where can I download the patches?В¶

The patches are available at http://kernel.org/ Most recent patches are linked from the front page, but they also have specific homes.

The 4.x.y (-stable) and 4.x patches live at

The 4.x kernels¶

These are the base stable releases released by Linus. The highest numbered release is the most recent.

To apply a patch moving from 4.6 to 4.7, you’d do the following (note that such patches do NOT apply on top of 4.x.y kernels but on top of the base 4.x kernel – if you need to move from 4.x.y to 4.x+1 you need to first revert the 4.x.y patch).

Here are some examples:

The 4.x.y kernels¶

This is the recommended branch for users who want the most recent stable kernel and are not interested in helping test development/experimental versions.

If no 4.x.y kernel is available, then the highest numbered 4.x kernel is the current stable kernel.

These patches are not incremental, meaning that for example the 4.7.3 patch does not apply on top of the 4.7.2 kernel source, but rather on top of the base 4.7 kernel source.

So, in order to apply the 4.7.3 patch to your existing 4.7.2 kernel source you have to first back out the 4.7.2 patch (so you are left with a base 4.7 kernel source) and then apply the new 4.7.3 patch.

Here’s a small example:

These are release-candidate kernels. These are development kernels released by Linus whenever he deems the current git (the kernel’s source management tool) tree to be in a reasonably sane state adequate for testing.

These kernels are not stable and you should expect occasional breakage if you intend to run them. This is however the most stable of the main development branches and is also what will eventually turn into the next stable kernel, so it is important that it be tested by as many people as possible.

So, 4.8-rc5 means that this is the fifth release candidate for the 4.8 kernel and the patch should be applied on top of the 4.7 kernel source.

Here are 3 examples of how to apply these patches:

This concludes this list of explanations of the various kernel trees. I hope you are now clear on how to apply the various patches and help testing the kernel.

Thank you’s to Randy Dunlap, Rolf Eike Beer, Linus Torvalds, Bodo Eggert, Johannes Stezenbach, Grant Coady, Pavel Machek and others that I may have forgotten for their reviews and contributions to this document.