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b=dYXszJ5oe67RruDyeIQGzsNJ8eEnvYyq9FwMlyWx+GWSKMY3Gzzo37yxTA/VCK7lGLqAL3 4i4NYBhMAp+/8O6twHAvF4+JwpDQZOa1VIEzLCWx+P1DMyyc4mOdd0axfuZiTCy/Frmnkt HR7ona92HVO8sS258u+fIWqXUoGIDi4= Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=nr1IWUdR; spf=pass (imf08.hostedemail.com: domain of jarkko@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=jarkko@kernel.org; dmarc=pass (policy=none) header.from=kernel.org X-Stat-Signature: ozjqw5e1jwet9ox5qsntpp7nrsmgqioq X-Rspamd-Queue-Id: 7795216000B X-Rspamd-Server: rspam02 X-Rspam-User: X-HE-Tag: 1666555775-259551 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sun, Oct 23, 2022 at 11:07:47PM +0300, Jarkko Sakkinen wrote: > On Wed, Oct 19, 2022 at 11:49:42AM +0800, Kefeng Wang wrote: > > Simplify VM_READ|VM_WRITE|VM_EXEC with VM_ACCESS_FLAGS. > > > > Cc: Jarkko Sakkinen > > Cc: Dave Hansen > > Signed-off-by: Kefeng Wang > > --- > > arch/x86/kernel/cpu/sgx/encl.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c > > index 1ec20807de1e..6225c525372d 100644 > > --- a/arch/x86/kernel/cpu/sgx/encl.c > > +++ b/arch/x86/kernel/cpu/sgx/encl.c > > @@ -268,7 +268,7 @@ static struct sgx_encl_page *sgx_encl_load_page_in_vma(struct sgx_encl *encl, > > unsigned long addr, > > unsigned long vm_flags) > > { > > - unsigned long vm_prot_bits = vm_flags & (VM_READ | VM_WRITE | VM_EXEC); > > + unsigned long vm_prot_bits = vm_flags & VM_ACCESS_FLAGS; > > struct sgx_encl_page *entry; > > > > entry = xa_load(&encl->page_array, PFN_DOWN(addr)); > > @@ -502,7 +502,7 @@ static void sgx_vma_open(struct vm_area_struct *vma) > > int sgx_encl_may_map(struct sgx_encl *encl, unsigned long start, > > unsigned long end, unsigned long vm_flags) > > { > > - unsigned long vm_prot_bits = vm_flags & (VM_READ | VM_WRITE | VM_EXEC); > > + unsigned long vm_prot_bits = vm_flags & VM_ACCESS_FLAGS; > > struct sgx_encl_page *page; > > unsigned long count = 0; > > int ret = 0; > > -- > > 2.35.3 > > > > Why? Only benefit I see is a downside: you have xref VM_ACCESS_FLAGS, which is counter-productive. Zero gain. BR, Jarkko