Monday, July 26, 2021

macOS 11.5.1

Juli Clover:

According to Apple, macOS Big Sur 11.5.1 brings important security updates and is recommended for all users.


Impact: An application may be able to execute arbitrary code with kernel privileges. Apple is aware of a report that this issue may have been actively exploited.

Description: A memory corruption issue was addressed with improved memory handling.

I encountered some problems applying this update (on top of 11.5). Software Update repeatedly stopped the download midway. After the download had completed, clicking the button to install it would try to download it again instead of restarting the Mac to begin installation.

See also: Mr. Macintosh (tweet, standalone download link), Howard Oakley.


Update (2021-07-26): See also: Pierre Igot.

Update (2021-08-04): Howard Oakley:

Updating macOS has never been more painful and fraught than in Big Sur. What had previously been a periodic distraction has changed in the last eight months into an unreliable and inefficient mess, which all too often consumes time when I can least afford it.


Last weeks’ security patch was an excellent example, in that it brought one small but very important fix for a bug, which didn’t apparently require a new kernel, firmware revision, or any discernible changes in the build or version numbers of the contents of /System/Library. Yet for M1 Macs it required the download of over 3 GB, fifteen minutes ‘preparation’, and a further 20-30 minutes to install.

Even if you’ve followed Apple’s advice and set up a Content Caching Server, each M1 Mac to be updated requires just under 1 GB of that update to be freshly downloaded direct from Apple’s servers rather than the local cache.


6 Comments RSS · Twitter

Continuous kernel panics after installation. Happened with 11.5 as well but resetting SMC did the trick. Not so now - PRAM, SMC resets don't do anything, apple diagnostics says its fine, but the machine is toast halfway through loading the user account. Tired of this shit, latest in a string of disappointments with the 16" 2019 MBP.

@Nick Sorry to hear that. It worked fine on my 16" 2019 MBP.

I had a lot df trouble installing 11.5 and 11.5.1. The update file would unpack and fail repeatedly for both updates:

Eventually I had to use System Recovery to install 11.5.1.

"After the download had completed, clicking the button to install it would try to download it again instead of restarting the Mac to begin installation."

I found that when the download restarts, quitting System Preferences allowed the restart to take place, with no ill effects. Apparently it's trying to re-download and restart at the same time.

Oh, joy, now the Finder won’t open (managed to spend all morning without noticing). Logs indicate the binary signature cannot be validated, so am now reinstalling from System Recovery twice in 24h.

Peter Maurer

+1 for problematic software update downloads. I had to download 11.5 twice because of an error after the first download (but before the preparation step), and the thing just happened after my first attempt to download 11.5.1.

As if Apple's new fondness for giant update file sizes weren't bad enough, we now have to get used to multiplying those sizes by 2 or more. Makes me feel sorry for those on slow or non-flatrate connections.

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