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process_runtime: fix address range query
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@mmisono
mmisono committed Jan 10, 2025
1 parent 207a63b commit 783f2b3
Showing 1 changed file with 38 additions and 28 deletions.
66 changes: 38 additions & 28 deletions kernel/src/process_runtime/runtime.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -119,11 +119,12 @@ impl MmapManager {

pub fn lookup(&self, addr: usize) -> Option<&MmapInfo> {
// Search for the range that contains the address
self.mappings
.range(..=RangeWrapper(addr..(addr + 1))) // Find all ranges up to the address
.rev() // Reverse the iterator to start from the largest range
.find(|(range, _)| range.0.contains(&addr)) // Check if the range contains the address
.map(|(_, info)| info) // Return the associated MmapInfo
for (range, info) in self.mappings.range(..=RangeWrapper(addr..usize::max_value())).rev() {
if range.0.contains(&addr) {
return Some(info);
}
}
None
}
}

Expand Down Expand Up @@ -252,6 +253,7 @@ pub fn invoke_trustlet(params: &mut RequestParams) -> Result<(), SvsmReqError> {
// update trustlet's page table
let flags = ProcessPageFlags::FLAG_REUSE;
page_table_ref.map_4k_page(dst, new_page, flags);
log::info!("Mapped new page for the trustlet at 0x{:x}", trustlet.pf_target_vaddr);
}
}

Expand Down Expand Up @@ -716,6 +718,8 @@ impl ProcessRuntime for PALContext {
// example: [1..3] < [2..4] < [2..5] < [3..4]
// page fault hander uses mmap infomation whose range contains the faulting address
// and priority is given to the latter one in the order
// FIXME: as the ordering above does not consider the time of mapping,
// the mmap handler might not use the latest mapping that includes the faulting address
mmap_manger.add_mapping(addr as usize, size as usize, fd as i32, offset as usize);

// Allocate virtul memory address
Expand Down Expand Up @@ -892,11 +896,12 @@ impl ProcessRuntime for PALContext {
const PF_RESERVED: u64 = 1 << 3;
const PF_INSTRUCTION: u64 = 1 << 4;
let mmap_manager = &self.process.mmap_manager;
log::info!("[Trustlet] #PF: CR2=0x{:x}", cr2);
if let Some(mmap_info) = mmap_manager.lookup(cr2 as usize) {
log::info!(" [Trustlet] Found file mapping: mmap_info={:?}", mmap_info);
log::info!("Found file mapping: mmap_info={:?}", mmap_info);
if error_code & PF_PRESENT == 0 {
// non-presente page
log::debug!(" [Trustlet] Page fault: not present page");
log::debug!("[Trustlet] Page fault: not present page");
let target_page_addr = cr2 & !0xFFF;
self.process.pf_target_vaddr = target_page_addr;
assert!(target_page_addr >= mmap_info.addr as u64);
Expand All @@ -923,19 +928,25 @@ impl ProcessRuntime for PALContext {
// make a guest request to load the page
self.return_value = TrustletReturnType::MMAP as u64;
return false;
} else if error_code & PF_PRESENT != 0 && error_code & PF_WRITE != 0 {
// CoW
let mut page_table_ref = ProcessPageTableRef::default();
page_table_ref.set_external_table(self.vmsa.cr3);
// Handle CoW
log::debug!(" [Trustlet] CoW: RIP={:#x}, CR2={:#x}, Error code={:?}", rip, cr2, error_code);
let user_access = error_code & PF_USER != 0;
let handled = page_table_ref.handle_cow(VirtAddr::from(cr2), user_access);
if handled {
log::debug!(" [Trustlet] CoW: handled");
return true;
}
} else {
log::info!("[Trustlet] #PF on present mmaped-page");
}
} else {
log::info!("[Trustlet] #PF: address is not mmaped-page");
}
if error_code & PF_PRESENT != 0 && error_code & PF_WRITE != 0 {
// CoW
let mut page_table_ref = ProcessPageTableRef::default();
page_table_ref.set_external_table(self.vmsa.cr3);
// Handle CoW
log::debug!("[Trustlet] CoW: RIP={:#x}, CR2={:#x}, Error code={:?}", rip, cr2, error_code);
let user_access = error_code & PF_USER != 0;
let handled = page_table_ref.handle_cow(VirtAddr::from(cr2), user_access);
if handled {
log::debug!("[Trustlet] CoW: handled");
return true;
}
log::info!("[Trustlet] [BUG] CoW: not handled");
}

// XXX: it should not come here
Expand All @@ -946,7 +957,7 @@ impl ProcessRuntime for PALContext {
let cr4 = self.vmsa.cr4;
let rsp = self.vmsa.rsp;
let rflags = self.vmsa.rflags;
log::info!(" [Trustlet] Page Fault!");
log::info!("[Trustlet] [BUG] Unhandled Page Fault!");
log::info!("vmsa EFER: {:?}", efer);
log::info!("vmsa CR2: {:?}", cr2);
log::info!("vmsa cr4: {:?}", cr4);
Expand All @@ -963,7 +974,7 @@ impl ProcessRuntime for PALContext {
let offset = (rsp & 0xFFF) / 8;
let (_mapping, stack_mapping) = map_paddr!(stack_base_paddr);
for i in 0..9 {
log::info!(" [Trustlet] Stack (rsp+{}): {:#x}", i*8, unsafe{stack_mapping.as_ptr::<u64>().offset((offset + i).try_into().unwrap()).read()});
log::info!("[Trustlet] Stack (rsp+{}): {:#x}", i*8, unsafe{stack_mapping.as_ptr::<u64>().offset((offset + i).try_into().unwrap()).read()});
}

/*
Expand All @@ -974,22 +985,21 @@ impl ProcessRuntime for PALContext {
return true;
*/

// #PF for other reasons
log::info!(" [Trustlet] Unhandled #PF: RIP={:#x}, CR2={:#x}, Error code={:?}", rip, cr2, error_code);
log::info!("[Trustlet] #PF: RIP={:#x}, CR2={:#x}, Error code={:?}", rip, cr2, error_code);
if error_code & PF_PRESENT == 0 {
log::info!(" [Trustlet] Page fault: not present");
log::info!("[Trustlet] Page fault: not present");
}
if error_code & PF_WRITE != 0 {
log::info!(" [Trustlet] Page fault: write");
log::info!("[Trustlet] Page fault: write");
}
if error_code & PF_USER != 0 {
log::info!(" [Trustlet] Page fault: user");
log::info!("[Trustlet] Page fault: user");
}
if error_code & PF_RESERVED != 0 {
log::info!(" [Trustlet] Page fault: reserved");
log::info!("[Trustlet] Page fault: reserved");
}
if error_code & PF_INSTRUCTION != 0 {
log::info!(" [Trustlet] Page fault: instruction fetch");
log::info!("[Trustlet] Page fault: instruction fetch");
}
false
}
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