This series includes some bug fixes and cleanups for kexec.
Yuntao Wang (3):
kexec_file: fix incorrect end value passed to
kimage_is_destination_range()
kexec_file: fix incorrect temp_start value in
locate_mem_hole_top_down()
x86/kexec: use pr_err() instead of pr_debug() when an error occurs
arch/x86/kernel/kexec-bzimage64.c | 2 +-
kernel/kexec_file.c | 11 +++++------
mm/highmem.c | 2 --
3 files changed, 6 insertions(+), 9 deletions(-)
--
2.43.0
The end parameter received by kimage_is_destination_range() should be the
last valid byte address of the target memory segment plus 1. However, in
the locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions,
the corresponding value passed to kimage_is_destination_range() is the last
valid byte address of the target memory segment, which is 1 less. Fix it.
Signed-off-by: Yuntao Wang <[email protected]>
---
kernel/kexec_file.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index f9a419cd22d4..26be070d3bdd 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -435,13 +435,12 @@ static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
if (temp_start < start || temp_start < kbuf->buf_min)
return 0;
- temp_end = temp_start + kbuf->memsz - 1;
-
/*
* Make sure this does not conflict with any of existing
* segments
*/
- if (kimage_is_destination_range(image, temp_start, temp_end)) {
+ if (kimage_is_destination_range(image, temp_start,
+ temp_start + kbuf->memsz)) {
temp_start = temp_start - PAGE_SIZE;
continue;
}
@@ -475,7 +474,7 @@ static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
* Make sure this does not conflict with any of existing
* segments
*/
- if (kimage_is_destination_range(image, temp_start, temp_end)) {
+ if (kimage_is_destination_range(image, temp_start, temp_end + 1)) {
temp_start = temp_start + PAGE_SIZE;
continue;
}
--
2.43.0
temp_end represents the address of the last available byte. Therefore, the
starting address of the memory segment with temp_end as its last available
byte and a size of `kbuf->memsz`, that is, the value of temp_start, should
be `temp_end - kbuf->memsz + 1` instead of `temp_end - kbuf->memsz`.
Additionally, use the ALIGN_DOWN macro instead of open-coding it directly
in locate_mem_hole_top_down() to improve code readability.
Signed-off-by: Yuntao Wang <[email protected]>
---
kernel/kexec_file.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 26be070d3bdd..c3bf52a9a8ad 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -426,11 +426,11 @@ static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
unsigned long temp_start, temp_end;
temp_end = min(end, kbuf->buf_max);
- temp_start = temp_end - kbuf->memsz;
+ temp_start = temp_end - kbuf->memsz + 1;
do {
/* align down start */
- temp_start = temp_start & (~(kbuf->buf_align - 1));
+ temp_start = ALIGN_DOWN(temp_start, kbuf->buf_align);
if (temp_start < start || temp_start < kbuf->buf_min)
return 0;
--
2.43.0
When an error is detected, use pr_err() instead of pr_debug() to output
log message.
In addition, remove the unnecessary return from set_page_address().
Signed-off-by: Yuntao Wang <[email protected]>
---
arch/x86/kernel/kexec-bzimage64.c | 2 +-
mm/highmem.c | 2 --
2 files changed, 1 insertion(+), 3 deletions(-)
diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c
index a61c12c01270..472a45dbc79a 100644
--- a/arch/x86/kernel/kexec-bzimage64.c
+++ b/arch/x86/kernel/kexec-bzimage64.c
@@ -424,7 +424,7 @@ static void *bzImage64_load(struct kimage *image, char *kernel,
* command line. Make sure it does not overflow
*/
if (cmdline_len + MAX_ELFCOREHDR_STR_LEN > header->cmdline_size) {
- pr_debug("Appending elfcorehdr=<addr> to command line exceeds maximum allowed length\n");
+ pr_err("Appending elfcorehdr=<addr> to command line exceeds maximum allowed length\n");
return ERR_PTR(-EINVAL);
}
diff --git a/mm/highmem.c b/mm/highmem.c
index e19269093a93..bd48ba445dd4 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -799,8 +799,6 @@ void set_page_address(struct page *page, void *virtual)
}
spin_unlock_irqrestore(&pas->lock, flags);
}
-
- return;
}
void __init page_address_init(void)
--
2.43.0
Yuntao Wang <[email protected]> writes:
> The end parameter received by kimage_is_destination_range() should be the
> last valid byte address of the target memory segment plus 1. However, in
> the locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions,
> the corresponding value passed to kimage_is_destination_range() is the last
> valid byte address of the target memory segment, which is 1 less. Fix
> it.
If that is true we I think we should rather fix
kimage_is_destination_range.
Otherwise we run the risk of having areas whose end is not
representable, epecially on 32bit.
Eric
> Signed-off-by: Yuntao Wang <[email protected]>
> ---
> kernel/kexec_file.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> index f9a419cd22d4..26be070d3bdd 100644
> --- a/kernel/kexec_file.c
> +++ b/kernel/kexec_file.c
> @@ -435,13 +435,12 @@ static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
> if (temp_start < start || temp_start < kbuf->buf_min)
> return 0;
>
> - temp_end = temp_start + kbuf->memsz - 1;
> -
> /*
> * Make sure this does not conflict with any of existing
> * segments
> */
> - if (kimage_is_destination_range(image, temp_start, temp_end)) {
> + if (kimage_is_destination_range(image, temp_start,
> + temp_start + kbuf->memsz)) {
> temp_start = temp_start - PAGE_SIZE;
> continue;
> }
> @@ -475,7 +474,7 @@ static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
> * Make sure this does not conflict with any of existing
> * segments
> */
> - if (kimage_is_destination_range(image, temp_start, temp_end)) {
> + if (kimage_is_destination_range(image, temp_start, temp_end + 1)) {
> temp_start = temp_start + PAGE_SIZE;
> continue;
> }
On 12/15/23 at 11:46am, Eric W. Biederman wrote:
> Yuntao Wang <[email protected]> writes:
>
> > The end parameter received by kimage_is_destination_range() should be the
> > last valid byte address of the target memory segment plus 1. However, in
> > the locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions,
> > the corresponding value passed to kimage_is_destination_range() is the last
> > valid byte address of the target memory segment, which is 1 less. Fix
> > it.
>
> If that is true we I think we should rather fix
> kimage_is_destination_range.
It's true wit the current implementation of
kimage_is_destination_range(). Its callers pass the start/end+1
pair. Agree we should fix kimage_is_destination_range() instead and
adjust callers, such as kimage_alloc_normal_control_pages(), and
kimage_alloc_page().
>
> Otherwise we run the risk of having areas whose end is not
> representable, epecially on 32bit.
>
>
> Eric
>
>
> > Signed-off-by: Yuntao Wang <[email protected]>
> > ---
> > kernel/kexec_file.c | 7 +++----
> > 1 file changed, 3 insertions(+), 4 deletions(-)
> >
> > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> > index f9a419cd22d4..26be070d3bdd 100644
> > --- a/kernel/kexec_file.c
> > +++ b/kernel/kexec_file.c
> > @@ -435,13 +435,12 @@ static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
> > if (temp_start < start || temp_start < kbuf->buf_min)
> > return 0;
> >
> > - temp_end = temp_start + kbuf->memsz - 1;
> > -
> > /*
> > * Make sure this does not conflict with any of existing
> > * segments
> > */
> > - if (kimage_is_destination_range(image, temp_start, temp_end)) {
> > + if (kimage_is_destination_range(image, temp_start,
> > + temp_start + kbuf->memsz)) {
> > temp_start = temp_start - PAGE_SIZE;
> > continue;
> > }
> > @@ -475,7 +474,7 @@ static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
> > * Make sure this does not conflict with any of existing
> > * segments
> > */
> > - if (kimage_is_destination_range(image, temp_start, temp_end)) {
> > + if (kimage_is_destination_range(image, temp_start, temp_end + 1)) {
> > temp_start = temp_start + PAGE_SIZE;
> > continue;
> > }
>
> _______________________________________________
> kexec mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/kexec
>
The end parameter received by kimage_is_destination_range() should be the
last valid byte address of the target memory segment plus 1. However, in
the locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions,
the corresponding value passed to kimage_is_destination_range() is the last
valid byte address of the target memory segment, which is 1 less.
There are two ways to fix this bug. We can either correct the logic of the
locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions, or we
can fix kimage_is_destination_range() by making the end parameter represent
the last valid byte address of the target memory segment. Here, we choose
the second approach.
Due to the modification to kimage_is_destination_range(), we also need to
adjust its callers, such as kimage_alloc_normal_control_pages() and
kimage_alloc_page().
Signed-off-by: Yuntao Wang <[email protected]>
---
v1->v2:
Fix this issue using the approach suggested by Eric and Baoquan.
As this patch is independent of the other patches in this series, I sent
out the v2 patch separately. If it's inconvenient for anyone, I can
resend the entire series again.
kernel/kexec_core.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index be5642a4ec49..5991b3ae072c 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -276,8 +276,8 @@ int kimage_is_destination_range(struct kimage *image,
unsigned long mstart, mend;
mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz;
- if ((end > mstart) && (start < mend))
+ mend = mstart + image->segment[i].memsz - 1;
+ if ((end >= mstart) && (start <= mend))
return 1;
}
@@ -372,7 +372,7 @@ static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
addr = pfn << PAGE_SHIFT;
eaddr = epfn << PAGE_SHIFT;
if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) ||
- kimage_is_destination_range(image, addr, eaddr)) {
+ kimage_is_destination_range(image, addr, eaddr - 1)) {
list_add(&pages->lru, &extra_pages);
pages = NULL;
}
@@ -716,7 +716,7 @@ static struct page *kimage_alloc_page(struct kimage *image,
/* If the page is not a destination page use it */
if (!kimage_is_destination_range(image, addr,
- addr + PAGE_SIZE))
+ addr + PAGE_SIZE - 1))
break;
/*
--
2.43.0
On 12/16/23 at 12:18pm, Yuntao Wang wrote:
> The end parameter received by kimage_is_destination_range() should be the
> last valid byte address of the target memory segment plus 1. However, in
> the locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions,
> the corresponding value passed to kimage_is_destination_range() is the last
> valid byte address of the target memory segment, which is 1 less.
>
> There are two ways to fix this bug. We can either correct the logic of the
> locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions, or we
> can fix kimage_is_destination_range() by making the end parameter represent
> the last valid byte address of the target memory segment. Here, we choose
> the second approach.
>
> Due to the modification to kimage_is_destination_range(), we also need to
> adjust its callers, such as kimage_alloc_normal_control_pages() and
> kimage_alloc_page().
>
> Signed-off-by: Yuntao Wang <[email protected]>
> ---
> v1->v2:
> Fix this issue using the approach suggested by Eric and Baoquan.
>
> As this patch is independent of the other patches in this series, I sent
> out the v2 patch separately. If it's inconvenient for anyone, I can
> resend the entire series again.
>
> kernel/kexec_core.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
> index be5642a4ec49..5991b3ae072c 100644
> --- a/kernel/kexec_core.c
> +++ b/kernel/kexec_core.c
> @@ -276,8 +276,8 @@ int kimage_is_destination_range(struct kimage *image,
> unsigned long mstart, mend;
>
> mstart = image->segment[i].mem;
> - mend = mstart + image->segment[i].memsz;
> - if ((end > mstart) && (start < mend))
> + mend = mstart + image->segment[i].memsz - 1;
> + if ((end >= mstart) && (start <= mend))
> return 1;
> }
>
> @@ -372,7 +372,7 @@ static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
> addr = pfn << PAGE_SHIFT;
> eaddr = epfn << PAGE_SHIFT;
eaddr = epfn << PAGE_SHIFT - 1;
The overall looks good to me, one tiny concern is I would like to
have 'eaddr' changed as above if a specific local variable has been
defined.
> if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) ||
> - kimage_is_destination_range(image, addr, eaddr)) {
> + kimage_is_destination_range(image, addr, eaddr - 1)) {
Then we have:
+ kimage_is_destination_range(image, addr, eaddr)) {
> list_add(&pages->lru, &extra_pages);
> pages = NULL;
> }
> @@ -716,7 +716,7 @@ static struct page *kimage_alloc_page(struct kimage *image,
>
> /* If the page is not a destination page use it */
> if (!kimage_is_destination_range(image, addr,
> - addr + PAGE_SIZE))
> + addr + PAGE_SIZE - 1))
> break;
>
> /*
> --
> 2.43.0
>
The end parameter received by kimage_is_destination_range() should be the
last valid byte address of the target memory segment plus 1. However, in
the locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions,
the corresponding value passed to kimage_is_destination_range() is the last
valid byte address of the target memory segment, which is 1 less.
There are two ways to fix this bug. We can either correct the logic of the
locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions, or we
can fix kimage_is_destination_range() by making the end parameter represent
the last valid byte address of the target memory segment. Here, we choose
the second approach.
Due to the modification to kimage_is_destination_range(), we also need to
adjust its callers, such as kimage_alloc_normal_control_pages() and
kimage_alloc_page().
Signed-off-by: Yuntao Wang <[email protected]>
---
v1->v2:
Fix this issue using the approach suggested by Eric and Baoquan.
As this patch is independent of the other patches in this series, I sent
out the v2 patch separately. If it's inconvenient for anyone, I can
resend the entire series again.
v2->v3:
Modify the assignment of eaddr as suggested by Baoquan.
kernel/kexec_core.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index be5642a4ec49..e65e8f186eff 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -276,8 +276,8 @@ int kimage_is_destination_range(struct kimage *image,
unsigned long mstart, mend;
mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz;
- if ((end > mstart) && (start < mend))
+ mend = mstart + image->segment[i].memsz - 1;
+ if ((end >= mstart) && (start <= mend))
return 1;
}
@@ -370,7 +370,7 @@ static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
pfn = page_to_boot_pfn(pages);
epfn = pfn + count;
addr = pfn << PAGE_SHIFT;
- eaddr = epfn << PAGE_SHIFT;
+ eaddr = epfn << PAGE_SHIFT - 1;
if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) ||
kimage_is_destination_range(image, addr, eaddr)) {
list_add(&pages->lru, &extra_pages);
@@ -716,7 +716,7 @@ static struct page *kimage_alloc_page(struct kimage *image,
/* If the page is not a destination page use it */
if (!kimage_is_destination_range(image, addr,
- addr + PAGE_SIZE))
+ addr + PAGE_SIZE - 1))
break;
/*
--
2.43.0
The end parameter received by kimage_is_destination_range() should be the
last valid byte address of the target memory segment plus 1. However, in
the locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions,
the corresponding value passed to kimage_is_destination_range() is the last
valid byte address of the target memory segment, which is 1 less.
There are two ways to fix this bug. We can either correct the logic of the
locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions, or we
can fix kimage_is_destination_range() by making the end parameter represent
the last valid byte address of the target memory segment. Here, we choose
the second approach.
Due to the modification to kimage_is_destination_range(), we also need to
adjust its callers, such as kimage_alloc_normal_control_pages() and
kimage_alloc_page().
Signed-off-by: Yuntao Wang <[email protected]>
---
v1->v2:
Fix this issue using the approach suggested by Eric and Baoquan.
As this patch is independent of the other patches in this series, I sent
out the v2 patch separately. If it's inconvenient for anyone, I can
resend the entire series again.
v2->v3:
Modify the assignment of eaddr as suggested by Baoquan.
v3->v4:
`eaddr = epfn << PAGE_SHIFT - 1` causes a compilation warning, fix it.
kernel/kexec_core.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index be5642a4ec49..e3b1a699f087 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -276,8 +276,8 @@ int kimage_is_destination_range(struct kimage *image,
unsigned long mstart, mend;
mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz;
- if ((end > mstart) && (start < mend))
+ mend = mstart + image->segment[i].memsz - 1;
+ if ((end >= mstart) && (start <= mend))
return 1;
}
@@ -370,7 +370,7 @@ static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
pfn = page_to_boot_pfn(pages);
epfn = pfn + count;
addr = pfn << PAGE_SHIFT;
- eaddr = epfn << PAGE_SHIFT;
+ eaddr = (epfn << PAGE_SHIFT) - 1;
if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) ||
kimage_is_destination_range(image, addr, eaddr)) {
list_add(&pages->lru, &extra_pages);
@@ -716,7 +716,7 @@ static struct page *kimage_alloc_page(struct kimage *image,
/* If the page is not a destination page use it */
if (!kimage_is_destination_range(image, addr,
- addr + PAGE_SIZE))
+ addr + PAGE_SIZE - 1))
break;
/*
--
2.43.0
On 12/16/23 at 08:05pm, Yuntao Wang wrote:
> The end parameter received by kimage_is_destination_range() should be the
> last valid byte address of the target memory segment plus 1. However, in
> the locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions,
> the corresponding value passed to kimage_is_destination_range() is the last
> valid byte address of the target memory segment, which is 1 less.
>
> There are two ways to fix this bug. We can either correct the logic of the
> locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions, or we
> can fix kimage_is_destination_range() by making the end parameter represent
> the last valid byte address of the target memory segment. Here, we choose
> the second approach.
>
> Due to the modification to kimage_is_destination_range(), we also need to
> adjust its callers, such as kimage_alloc_normal_control_pages() and
> kimage_alloc_page().
>
> Signed-off-by: Yuntao Wang <[email protected]>
> ---
> v1->v2:
> Fix this issue using the approach suggested by Eric and Baoquan.
>
> As this patch is independent of the other patches in this series, I sent
> out the v2 patch separately. If it's inconvenient for anyone, I can
> resend the entire series again.
>
> v2->v3:
> Modify the assignment of eaddr as suggested by Baoquan.
>
> v3->v4:
> `eaddr = epfn << PAGE_SHIFT - 1` causes a compilation warning, fix it.
>
> kernel/kexec_core.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
The whole series looks good to me with this v4 of patch 1, you may need
to reorganize them and repost.
Acked-by: Baoquan He <[email protected]>
>
> diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
> index be5642a4ec49..e3b1a699f087 100644
> --- a/kernel/kexec_core.c
> +++ b/kernel/kexec_core.c
> @@ -276,8 +276,8 @@ int kimage_is_destination_range(struct kimage *image,
> unsigned long mstart, mend;
>
> mstart = image->segment[i].mem;
> - mend = mstart + image->segment[i].memsz;
> - if ((end > mstart) && (start < mend))
> + mend = mstart + image->segment[i].memsz - 1;
> + if ((end >= mstart) && (start <= mend))
> return 1;
> }
>
> @@ -370,7 +370,7 @@ static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
> pfn = page_to_boot_pfn(pages);
> epfn = pfn + count;
> addr = pfn << PAGE_SHIFT;
> - eaddr = epfn << PAGE_SHIFT;
> + eaddr = (epfn << PAGE_SHIFT) - 1;
> if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) ||
> kimage_is_destination_range(image, addr, eaddr)) {
> list_add(&pages->lru, &extra_pages);
> @@ -716,7 +716,7 @@ static struct page *kimage_alloc_page(struct kimage *image,
>
> /* If the page is not a destination page use it */
> if (!kimage_is_destination_range(image, addr,
> - addr + PAGE_SIZE))
> + addr + PAGE_SIZE - 1))
> break;
>
> /*
> --
> 2.43.0
>