Merge pull request rust-osdev#1143 from nicholasbishop/bishop-drop-pa…

…nic-log

uefi: Drop the panic-on-logger-errors feature

uefi/CHANGELOG.md

@@ -1,5 +1,9 @@
 # uefi - [Unreleased]
 
+## Removed
+- Removed the `panic-on-logger-errors` feature of the `uefi` crate. Logger
+  errors are now silently ignored.
+
 
 # uefi - 0.28.0 (2024-04-19)
 

uefi/Cargo.toml

@@ -13,7 +13,6 @@ repository.workspace = true
 rust-version.workspace = true
 
 [features]
-default = ["panic-on-logger-errors"]
 alloc = []
 
 # Generic gate to code that uses unstable features of Rust. You usually need a nightly toolchain.
@@ -23,10 +22,6 @@ unstable = []
 logger = []
 global_allocator = []
 panic_handler = []
-# Ignore text output errors in logger as a workaround for firmware issues that
-# were observed on the VirtualBox UEFI implementation (see uefi-rs#121).
-# In those cases, this feature can be excluded by removing the default features.
-panic-on-logger-errors = []
 qemu = ["dep:qemu-exit", "panic_handler"] # panic_handler: logical, not technical dependency
 
 [dependencies]

uefi/src/helpers/logger.rs

@@ -107,30 +107,17 @@ impl log::Log for Logger {
 
         if !output.is_null() {
             let writer = unsafe { &mut *output };
-            let result = DecoratedLog::write(
+
+            // Ignore all errors. Since we're in the logger implementation we
+            // can't log the error. We also don't want to panic, since logging
+            // is generally not critical functionality.
+            let _ = DecoratedLog::write(
                 writer,
                 record.level(),
                 record.args(),
                 record.file().unwrap_or("<unknown file>"),
                 record.line().unwrap_or(0),
             );
-
-            // Some UEFI implementations, such as the one used by VirtualBox,
-            // may intermittently drop out some text from SimpleTextOutput and
-            // report an EFI_DEVICE_ERROR. This will be reported here as an
-            // `fmt::Error`, and given how the `log` crate is designed, our main
-            // choices when that happens are to ignore the error or panic.
-            //
-            // Ignoring errors is bad, especially when they represent loss of
-            // precious early-boot system diagnosis data, so we panic by
-            // default. But if you experience this problem and want your UEFI
-            // application to keep running when it happens, you can disable the
-            // `panic-on-logger-errors` cargo feature. If you do so, logging errors
-            // will be ignored by `uefi-rs` instead.
-            //
-            if cfg!(feature = "panic-on-logger-errors") {
-                result.unwrap()
-            }
         }
     }
 

xtask/src/cargo.rs

@@ -50,7 +50,6 @@ pub enum Feature {
     Alloc,
     GlobalAllocator,
     Logger,
-    PanicOnLoggerErrors,
     Unstable,
     PanicHandler,
     Qemu,
@@ -70,7 +69,6 @@ impl Feature {
             Self::Alloc => "alloc",
             Self::GlobalAllocator => "global_allocator",
             Self::Logger => "logger",
-            Self::PanicOnLoggerErrors => "panic-on-logger-errors",
             Self::Unstable => "unstable",
             Self::PanicHandler => "panic_handler",
             Self::Qemu => "qemu",
@@ -91,7 +89,6 @@ impl Feature {
                 Self::Alloc,
                 Self::GlobalAllocator,
                 Self::Logger,
-                Self::PanicOnLoggerErrors,
                 Self::Unstable,
                 Self::PanicHandler,
                 Self::Qemu,