| Message ID | 1612348510-29569-2-git-send-email-hejinyang@loongson.cn (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2,1/2] MIPS: relocatable: Provide kaslr_offset() to get the kernel offset | expand |
On Wed, Feb 03, 2021 at 06:35:10PM +0800, Jinyang He wrote: > The type of the VMLINUX_LOAD_ADDRESS macro is the (unsigned long long) > in 32bits kernel but (unsigned long) in the 64-bit kernel. Although there > is no error here, avoid using it to calculate kaslr_offset. And here we > may need is that the address of __kaslr_offset rather than (void *)offset. > > Signed-off-by: Jinyang He <hejinyang@loongson.cn> > --- > arch/mips/kernel/relocate.c | 8 ++------ > 1 file changed, 2 insertions(+), 6 deletions(-) > > diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c > index 95abb9c..52018a3 100644 > --- a/arch/mips/kernel/relocate.c > +++ b/arch/mips/kernel/relocate.c > @@ -430,13 +430,9 @@ void *__init relocate_kernel(void) > */ > static void show_kernel_relocation(const char *level) > { > - unsigned long offset; > - > - offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS); > - > - if (IS_ENABLED(CONFIG_RELOCATABLE) && offset > 0) { > + if (__kaslr_offset > 0) { > printk(level); > - pr_cont("Kernel relocated by 0x%pK\n", (void *)offset); > + pr_cont("Kernel relocated by 0x%pK\n", &__kaslr_offset); are you sure ? I would have expected (void *)__kaslr_offset here. Thomas.
On 02/04/2021 11:36 PM, Thomas Bogendoerfer wrote: > On Wed, Feb 03, 2021 at 06:35:10PM +0800, Jinyang He wrote: >> The type of the VMLINUX_LOAD_ADDRESS macro is the (unsigned long long) >> in 32bits kernel but (unsigned long) in the 64-bit kernel. Although there >> is no error here, avoid using it to calculate kaslr_offset. And here we >> may need is that the address of __kaslr_offset rather than (void *)offset. >> >> Signed-off-by: Jinyang He <hejinyang@loongson.cn> >> --- >> arch/mips/kernel/relocate.c | 8 ++------ >> 1 file changed, 2 insertions(+), 6 deletions(-) >> >> diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c >> index 95abb9c..52018a3 100644 >> --- a/arch/mips/kernel/relocate.c >> +++ b/arch/mips/kernel/relocate.c >> @@ -430,13 +430,9 @@ void *__init relocate_kernel(void) >> */ >> static void show_kernel_relocation(const char *level) >> { >> - unsigned long offset; >> - >> - offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS); >> - >> - if (IS_ENABLED(CONFIG_RELOCATABLE) && offset > 0) { >> + if (__kaslr_offset > 0) { >> printk(level); >> - pr_cont("Kernel relocated by 0x%pK\n", (void *)offset); >> + pr_cont("Kernel relocated by 0x%pK\n", &__kaslr_offset); > are you sure ? I would have expected (void *)__kaslr_offset here. > > Thomas. > It is my fault. I misunderstood the meaning of 'by' and '@' because of my poor English. Thank you for pointing out my fault. I'll send v3 later. Thanks, Jinyang
diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c index 95abb9c..52018a3 100644 --- a/arch/mips/kernel/relocate.c +++ b/arch/mips/kernel/relocate.c @@ -430,13 +430,9 @@ void *__init relocate_kernel(void) */ static void show_kernel_relocation(const char *level) { - unsigned long offset; - - offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS); - - if (IS_ENABLED(CONFIG_RELOCATABLE) && offset > 0) { + if (__kaslr_offset > 0) { printk(level); - pr_cont("Kernel relocated by 0x%pK\n", (void *)offset); + pr_cont("Kernel relocated by 0x%pK\n", &__kaslr_offset); pr_cont(" .text @ 0x%pK\n", _text); pr_cont(" .data @ 0x%pK\n", _sdata); pr_cont(" .bss @ 0x%pK\n", __bss_start);
The type of the VMLINUX_LOAD_ADDRESS macro is the (unsigned long long) in 32bits kernel but (unsigned long) in the 64-bit kernel. Although there is no error here, avoid using it to calculate kaslr_offset. And here we may need is that the address of __kaslr_offset rather than (void *)offset. Signed-off-by: Jinyang He <hejinyang@loongson.cn> --- arch/mips/kernel/relocate.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)