On fsl_book3e, rodata is set read-only at the same time as
init text is set NX at the end of init. That's too early.
As both action are performed at the same time, delay both
actions to the time rodata is expected to be made read-only.
It means we will have a small window with init mem freed but
still executable. It shouldn't be an issue though, especially
because the said memory gets poisoned and should therefore
result to a bad instruction fault in case it gets executed.
mmu_mark_initmem_nx() is bailing out before doing anything when
CONFIG_STRICT_KERNEL_RWX is not selected or rodata_enabled is false.
mmu_mark_rodata_ro() is called only when CONFIG_STRICT_KERNEL_RWX
is selected and rodata_enabled is true so this is equivalent.
Move code from mmu_mark_initmem_nx() into mmu_mark_rodata_ro() and
remove the call to strict_kernel_rwx_enabled() which is not needed
anymore.
Fixes: d5970045cf ("powerpc/fsl_booke: Update of TLBCAMs after init")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2e35f0fd649c83c5add17a99514ac040767be93a.1652981047.git.christophe.leroy@csgroup.eu
arch/powerpc/mm/nohash/fsl_book3e.c: In function ‘relocate_init’:
arch/powerpc/mm/nohash/fsl_book3e.c:348:2: error: implicit declaration of function ‘early_get_first_memblock_info’
early_get_first_memblock_info(__va(dt_ptr), &size);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Add missing include file linux/of_fdt.h to fix this.
Fixes: 86c38fec69 ("powerpc: Remove asm/prom.h from all files that don't need it")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220517094830.27560-1-yuehaibing@huawei.com
Some functions defined in 'arch/powerpc/mm' are deserving of an
`__init` macro attribute. These functions are only called by other
initialization functions and therefore should inherit the attribute.
Also, change function declarations in header files to include `__init`.
Signed-off-by: Nick Child <nick.child@ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211216220035.605465-4-nick.child@ibm.com
Building with W=1 we see a warning:
linux/arch/powerpc/mm/nohash/fsl_book3e.c:63:15: error: no previous prototype for ‘tlbcam_sz’
tlbcam_sz() is not used outside this file, so we can make it static.
However it's only used inside #ifdef CONFIG_PPC32, so move it within
that ifdef, otherwise we would get a defined but not used error.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211124093254.1054750-4-mpe@ellerman.id.au
Building tqm8541_defconfig results in:
arch/powerpc/mm/nohash/fsl_book3e.c: In function 'settlbcam':
arch/powerpc/mm/nohash/fsl_book3e.c:126:40: error: '_PAGE_BAP_SX' undeclared (first use in this function)
126 | TLBCAM[index].MAS3 |= (flags & _PAGE_BAP_SX) ? MAS3_SX : 0;
| ^~~~~~~~~~~~
arch/powerpc/mm/nohash/fsl_book3e.c:126:40: note: each undeclared identifier is reported only once for each function it appears in
make[3]: *** [scripts/Makefile.build:277: arch/powerpc/mm/nohash/fsl_book3e.o] Error 1
make[2]: *** [scripts/Makefile.build:540: arch/powerpc/mm/nohash] Error 2
make[1]: *** [scripts/Makefile.build:540: arch/powerpc/mm] Error 2
make: *** [Makefile:1868: arch/powerpc] Error 2
This is because _PAGE_BAP_SX is not defined when using 32 bits PTE.
Now that _PAGE_EXEC contains both _PAGE_BAP_SX and _PAGE_BAP_UX, it can be used instead.
Fixes: 01116e6e98 ("powerpc/fsl_booke: Take exec flag into account when setting TLBCAMs")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/91a0235e7f2a85308b84aa5b9efd8d022e2b899a.1635226743.git.christophe.leroy@csgroup.eu