From: Mike Rapoport (Microsoft) <rppt@kernel.org>
Date: Sat, 23 May 2026 17:54:14 +0000 (+0300)
Subject: proc: replace __get_free_page() with kmalloc()
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cb7907e36c1054987a9709efc422b30e10ce839f;p=thirdparty%2Fkernel%2Flinux.git

proc: replace __get_free_page() with kmalloc()

A few functions in fs/proc/base.c use __get_free_page() to allocate a
temporary buffer.

kmalloc() is a better API for such use and it also provides better
scalability and more debugging possibilities.

Replace use of __get_free_page() with kmalloc().

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Link: https://patch.msgid.link/20260523-b4-fs-v1-2-275e36a83f0e@kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
---

diff --git a/fs/proc/base.c b/fs/proc/base.c
index d9acfa89c894b..e129dc509b794 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -261,7 +261,7 @@ static ssize_t get_mm_proctitle(struct mm_struct *mm, char __user *buf,
 	if (pos >= PAGE_SIZE)
 		return 0;
 
-	page = (char *)__get_free_page(GFP_KERNEL);
+	page = kmalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!page)
 		return -ENOMEM;
 
@@ -284,7 +284,7 @@ static ssize_t get_mm_proctitle(struct mm_struct *mm, char __user *buf,
 			ret = len;
 		}
 	}
-	free_page((unsigned long)page);
+	kfree(page);
 	return ret;
 }
 
@@ -347,7 +347,7 @@ static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf,
 	if (count > arg_end - pos)
 		count = arg_end - pos;
 
-	page = (char *)__get_free_page(GFP_KERNEL);
+	page = kmalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!page)
 		return -ENOMEM;
 
@@ -371,7 +371,7 @@ static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf,
 		count -= got;
 	}
 
-	free_page((unsigned long)page);
+	kfree(page);
 	return len;
 }
 
@@ -908,7 +908,7 @@ static ssize_t mem_rw(struct file *file, char __user *buf,
 	if (!mm)
 		return 0;
 
-	page = (char *)__get_free_page(GFP_KERNEL);
+	page = kmalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!page)
 		return -ENOMEM;
 
@@ -949,7 +949,7 @@ static ssize_t mem_rw(struct file *file, char __user *buf,
 
 	mmput(mm);
 free:
-	free_page((unsigned long) page);
+	kfree(page);
 	return copied;
 }
 
@@ -1016,7 +1016,7 @@ static ssize_t environ_read(struct file *file, char __user *buf,
 	if (!mm || !mm->env_end)
 		return 0;
 
-	page = (char *)__get_free_page(GFP_KERNEL);
+	page = kmalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!page)
 		return -ENOMEM;
 
@@ -1062,7 +1062,7 @@ static ssize_t environ_read(struct file *file, char __user *buf,
 	mmput(mm);
 
 free:
-	free_page((unsigned long) page);
+	kfree(page);
 	return ret;
 }