[PATCH v2 5/5] Add two entries:
Xiang W
wxjstz at 126.com
Thu Jan 19 06:01:14 PST 2023
在 2023-01-19星期四的 08:11 +0530,Himanshu Chauhan写道:
> On Wed, Jan 18, 2023 at 08:17:26PM +0800, Xiang W wrote:
> > 在 2023-01-18星期三的 17:07 +0530,Himanshu Chauhan写道:
> > > 1. TEXT: fw_start to _fw_rw_offset with RX permissions
> > > 2. DATA: _fw_rw_offset to fw_size with RW permissions
> > >
> > > These permissions are still not enforced from M-mode but lay
> > > the ground work for enforcing them for M-mode. SU-mode don't
> > > have any access to these regions.
> > >
> > > Sample output:
> > > Domain0 Region01 : 0x0000000080000000-0x000000008001ffff M: (R,X) S/U: ()
> > > Domain0 Region02 : 0x0000000080020000-0x000000008003ffff M: (R,W) S/U: ()
> > >
> > > Signed-off-by: Himanshu Chauhan <hchauhan at ventanamicro.com>
> > > ---
> > > lib/sbi/sbi_domain.c | 23 +++++++++++++++++++++--
> > > 1 file changed, 21 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/lib/sbi/sbi_domain.c b/lib/sbi/sbi_domain.c
> > > index f6addc4..3dceb6a 100644
> > > --- a/lib/sbi/sbi_domain.c
> > > +++ b/lib/sbi/sbi_domain.c
> > > @@ -637,12 +637,31 @@ int sbi_domain_init(struct sbi_scratch *scratch, u32 cold_hartid)
> > > u32 i;
> > > const struct sbi_platform *plat = sbi_platform_ptr(scratch);
> > >
> > > + if ((scratch->fw_rw_offset & (scratch->fw_rw_offset - 1)) != 0) {
> >
> > This expression is false at scratch-> fw_rw_offset = 0.
> > 0 is not a power of 2.
> > suggestion:
> > if ((scratch->fw_rw_offset & (scratch->fw_rw_offset - 1)) != 0 || scratch->fw_rw_offset == 0) {
>
> fw_rw_offset is provided by the linker. It will fall after text, ro, and symbols and then it is
> protected by LOG2CEIL. Unless everything is preceding fw_rw_offset is zero, fw_rw_offset can't
> be zero. So I think this check is safe here.
I know fw_rw_offset is provieded by the linker script. This check prevents
linker scripts from being incorrectly modified.
Regards,
Xiang W
>
> Regards
> Himanshu
>
> >
> > Regards,
> > Xiang W
> >
> > > + sbi_printf("%s: Firmware read-write offset not a power of 2 (0x%lx)\n",
> > > + __func__, scratch->fw_rw_offset);
> > > + return SBI_EINVAL;
> > > + }
> > > +
> > > + if ((scratch->fw_start & (scratch->fw_rw_offset - 1)) != 0) {
> > > + sbi_printf("%s: Firmware start and read-write offset not aligned\n",
> > > + __func__);
> > > + return SBI_EINVAL;
> > > + }
> > > +
> > > /* Root domain firmware memory region */
> > > - sbi_domain_memregion_init(scratch->fw_start, scratch->fw_size,
> > > - SBI_DOMAIN_MEMREGION_M_RWX,
> > > + sbi_domain_memregion_init(scratch->fw_start, scratch->fw_rw_offset,
> > > + (SBI_DOMAIN_MEMREGION_M_READABLE |
> > > + SBI_DOMAIN_MEMREGION_M_EXECUTABLE),
> > > &root_fw_region);
> > > domain_memregion_initfw(&root_memregs[root_memregs_count++]);
> > >
> > > + sbi_domain_memregion_init((scratch->fw_start + scratch->fw_rw_offset),
> > > + (scratch->fw_size - scratch->fw_rw_offset),
> > > + (SBI_DOMAIN_MEMREGION_M_READABLE |
> > > + SBI_DOMAIN_MEMREGION_M_WRITABLE),
> > > + &root_memregs[root_memregs_count++]);
> > > +
> > > /* Root domain allow everything memory region */
> > > sbi_domain_memregion_init(0, ~0UL,
> > > (SBI_DOMAIN_MEMREGION_READABLE |
> > > --
> > > 2.39.0
> > >
> > >
> >
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